2010 Chevrolet Express Owners Manual

Too little fluid could cause the transmission to overheat. Be sure to get an accurate reading if you check your transmission fluid. Wait at least 30 minutes with the engine Off, before checking the transmission fluid level if the vehicle has been driven: • In hot weather, when outside temperatures are

above 32°C (90°F).

• The vehicle is heavily loaded. • At high speed for quite a while in hot weather.

• In heavy traffic and hot weather. • While pulling a trailer. After driving under these conditions, a hot check can be performed. The fluid should be Hot, which is 71°C to 93°C (160°F to 200°F). A cold fluid level check can be performed after the vehicle has been sitting for eight hours or more with the engine Off, but this is used only as a reference. Let the engine run at idle for five minutes if outside temperatures is between 15°C to 32°C (60°F to 90°F). Should the fluid level be low during this cold check, the fluid must be checked Warm or Hot before adding fluid. If the outside temperature is colder than 15°C (60°F) or hotter than 32°C (90°F), a cold check cannot be performed. A warm fluid level check can be performed by driving the vehicle under lightly loaded conditions and outside temperatures between 10°C to 27°C (50°F to 80°F). The vehicle should be driven for at least 15 miles before performing a warm check. Checking the fluid Warm or Hot will give a more accurate reading of the fluid level than a cold check. Because the vehicle is equipped with a high-efficiency air-to-oil cooler, the transmission fluid temperature may not reach the required Hot fluid level checking temperature under normal lightly loaded driving vehicle conditions.

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Checking the Fluid Level Prepare the vehicle as follows: 1. Park the vehicle on a level place. Keep the engine

running.

2. With the parking brake applied, place the shift lever

in P (Park).

3. With foot on the brake pedal, move the shift

lever through each gear range, pausing for about three seconds in each range. When M is reached, move the selector from M1 through M3. Then, position the shift lever in P (Park).

4. Let the engine run at idle for two minutes or more. Then, without shutting Off the engine:

The transmission dipstick is located near the center of the engine compartment and will be labeled with the graphic shown.

See Engine Compartment Overview on page 6-14 for more information on location. 1. Flip the handle up and then pull out the dipstick

and wipe it with a clean rag or paper towel.

2. Push it back in all the way, wait three seconds and

then pull it back out again.

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A. COLD Range B. WARM Range C. HOT Range

3. Check both sides of the dipstick, and read the lower level. The fluid level must be in the COLD (A) range for a cold check, transmission temperature 27°C to 32°C (80°F to 90°F), between the COLD (A) and HOT (C) range for a WARM (B) check, 50°C to 60°C (122°F to 140°F) or in the HOT (C) cross-hatched range for a hot check, 71°C to 93°C (160°F to 200°F). Be sure to keep the dipstick pointed down to get an accurate reading.

4. If the fluid level is in the acceptable range, push the

dipstick back in all the way; then flip the handle down to lock the dipstick in place.

How to Add Automatic Transmission Fluid Refer to the Maintenance Schedule to determine what kind of transmission fluid to use. See Recommended Fluids and Lubricants on page 7-12.

A. WARM Range B. HOT Range Using a funnel, add fluid down the transmission dipstick tube only after checking the transmission fluid while it is warm or hot. A cold check is used only as a reference.

If the fluid level is low, add only enough of the proper fluid to bring the level up to the middle of the WARM (A) or HOT (B) range depending on the ambient temperature and prior driving conditions. Refer to “How to Check Automatic Transmission Fluid”, earlier in this section for instructions on driving to achieve warm or hot transmission fluid. It does not take much fluid, generally less than 0.5 L (one pint). Do not overfill. Notice: Use of the incorrect automatic transmission fluid may damage the vehicle, and the damages may not be covered by the vehicle’s warranty. Always use the automatic transmission fluid listed in Recommended Fluids and Lubricants on page 7-12. • After adding fluid, recheck the fluid level as described under “How to Check Automatic Transmission Fluid,” earlier in this section.

• When the correct fluid level is obtained, push the

dipstick back in all the way; then flip the handle down to lock the dipstick in place.

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Cooling System If your vehicle has a diesel engine, see “Van Models” under “Cooling System” in the DURAMAX® Diesel Supplement. The Cooling System allows the engine to maintain the correct working temperature.

{ WARNING:

An electric engine cooling fan under the hood can start up even when the engine is not running and can cause injury. Keep hands, clothing, and tools away from any underhood electric fan.

{ WARNING:

Heater, fuel operated heater (FOH), radiator hoses, and other engine parts, can be very hot. Do not touch them. If you do, you can be burned.

WARNING:

(Continued)

A. Radiator Pressure Cap B. Coolant Recovery Tank C. Engine Cooling Fan(s)

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Engine Coolant The cooling system in the vehicle is filled with DEX-COOL® engine coolant. This coolant is designed to remain in the vehicle for five years or 150,000 miles (240 000 km), whichever occurs first. The following explains the cooling system and how to check and add coolant when it is low. If there is a problem with engine overheating, see Engine Overheating on page 6-35.

WARNING:

(Continued)

Do not run the engine if there is a leak. If you run the engine, it could lose all coolant. That could cause an engine fire, and you could be burned. Get any leak fixed before you drive the vehicle.

Notice: Using coolant other than DEX-COOL may cause premature engine, heater core, radiator and fuel operated heater (FOH) corrosion. In addition, the engine coolant may require changing sooner, at 30,000 miles (50 000 km) or 24 months, whichever occurs first. Any repairs would not be covered by your warranty. Always use DEX-COOL (silicate-free) coolant in your vehicle.

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If an improper coolant mixture is used,

• Protects against rust and corrosion. • Will not damage aluminum parts. • Helps keep the proper engine temperature. Notice: the engine could overheat and be badly damaged. The repair cost would not be covered by the vehicle warranty. Too much water in the mixture can freeze and crack the engine, radiator, heater core, and other parts. Notice: in the vehicle’s cooling system, the vehicle could be damaged. Use only the proper mixture of the engine coolant listed in this manual for the cooling system. See Recommended Fluids and Lubricants on page 7-12 for more information.

If extra inhibitors and/or additives are used

What to Use

{ WARNING:

Adding only plain water to the cooling system can be dangerous. Plain water, or some other liquid such as alcohol, can boil before the proper coolant mixture will. The vehicle’s coolant warning system is set for the proper coolant mixture. With plain water or the wrong mixture, the engine could get too hot but you would not get the overheat warning. The engine could catch fire and you or others could be burned. Use a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant.

Use a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant. If using this mixture, nothing else needs to be added. This mixture: • Gives freezing protection down to −34°F (−37°C),

outside temperature.

• Gives boiling protection up to 265°F (129°C),

engine temperature.

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Checking Coolant The vehicle must be on a level surface when checking the coolant level. Check to see if coolant is visible in the coolant recovery tank. If the coolant inside the coolant recovery tank is boiling, do not do anything else until it cools down. If coolant is visible but the coolant level is not at or above the COLD FILL mark, add a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant at the coolant recovery tank, but be sure the cooling system is cool before this is done. When the engine is cold, the coolant level should be at or above the COLD FILL mark. If it is not, there could be a leak in the cooling system. If the coolant is low, add the coolant or take the vehicle to a dealer/retailer for service.

How to Add Coolant to the Recovery Tank for Gasoline Engines If your vehicle has a diesel engine, see “How to Add Coolant to the Coolant Recovery Tank” under “Van Models” in the Cooling System section of the DURAMAX® Diesel Supplement for the proper coolant fill procedure.

{ WARNING:

You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine.

Notice: This vehicle has a specific coolant fill procedure. Failure to follow this procedure could cause the engine to overheat and be severely damaged. If coolant is needed, add the proper DEX-COOL® coolant mixture at the coolant recovery tank.

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How to Add Coolant to the Radiator If your vehicle has a diesel engine, see “How to Add Coolant to the Radiator” under “Van Models” in the Cooling System section of the DURAMAX® Diesel Supplement for the proper radiator fill procedure.

{ WARNING:

An electric engine cooling fan under the hood can start up even when the engine is not running and can cause injury. Keep hands, clothing, and tools away from any underhood electric fan.

{ WARNING:

Steam and scalding liquids from a hot cooling system can blow out and burn you badly. They are under pressure, and if you turn the surge tank pressure cap — even a little — they can come out at high speed. Never turn the cap when the cooling system, including the surge tank pressure cap, is hot. Wait for the cooling system and surge tank pressure cap to cool if you ever have to turn the pressure cap.

If coolant is needed, add the proper mixture directly to the radiator, but be sure the cooling system is cool before this is done.

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1. You can remove the radiator pressure cap when

the cooling system, including the radiator pressure cap and upper radiator hose, is no longer hot. Turn the pressure cap slowly counterclockwise until it first stops. Do not press down while turning the pressure cap. If you hear a hiss, wait for that to stop. A hiss means there is still some pressure left.

2. Then keep turning the pressure cap, but now push

down as you turn it. Remove the pressure cap.

3. Fill the radiator with the proper DEX-COOL®

coolant mixture, up to the base of the filler neck. See Engine Coolant on page 6-29 for more information about the proper coolant mixture.

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4. Then fill the coolant recovery tank to the

COLD FILL mark.

5. Put the cap back on the coolant recovery tank, but

leave the radiator pressure cap off.

6. Start the engine and let it run until you can feel the

upper radiator hose getting hot. Watch out for the engine cooling fan.

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7. By this time, the coolant level inside the radiator filler neck may be lower. If the level is lower, add more of the proper DEX-COOL® coolant mixture through the filler neck until the level reaches the base of the filler neck.

8. Then replace the pressure cap. At any time during

this procedure if coolant begins to flow out of the filler neck, reinstall the pressure cap.

If the pressure cap is not tightly installed,

Notice: coolant loss and possible engine damage may occur. Be sure the cap is properly and tightly secured.

Engine Overheating If your vehicle has the DURAMAX Diesel engine, see the DURAMAX Diesel manual for more information. The vehicle has an indicator to warn of engine overheating. You will find an engine coolant temperature gage on your vehicle’s instrument panel. See Engine Coolant Temperature Gage on page 4-29 for more information.

You may decide not to lift the hood when this warning appears, but instead get service help right away. See Roadside Assistance Program on page 8-8. If you do decide to lift the hood, make sure the vehicle is parked on a level surface. Then check to see if the engine cooling fans are running. If the engine is overheating, both fans should be running. If they are not, do not continue to run the engine and have the vehicle serviced. See if the engine cooling fan speed increases when idle speed is doubled by pushing the accelerator pedal down. If it does not, your vehicle needs service. Turn off the engine. Notice: Engine damage from running the engine without coolant is not covered by the warranty. Notice: driven with no coolant, your vehicle can be badly damaged. The costly repairs would not be covered by the vehicle warranty.

If the engine catches fire because of being

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If Steam Is Coming From The Engine Compartment

{ WARNING:

Steam from an overheated engine can burn you badly, even if you just open the hood. Stay away from the engine if you see or hear steam coming from it. Just turn it off and get everyone away from the vehicle until it cools down. Wait until there is no sign of steam or coolant before you open the hood. If you keep driving when your engine is overheated, the liquids in it can catch fire. You or others could be badly burned. Stop your engine if it overheats, and get out of the vehicle until the engine is cool.

If No Steam Is Coming From The Engine Compartment If an engine overheat warning is displayed but no steam can be seen or heard, the problem may not be too serious. Sometimes the engine can get a little too hot when the vehicle: • Climbs a long hill on a hot day. • Stops after high-speed driving. • Idles for long periods in traffic. • Tows a trailer. See “Driving on Grades” under

Towing a Trailer on page 5-30.

If the overheat warning is displayed with no sign of steam: 1. Turn the air off. 2. Turn the heater on to the highest temperature and

to the highest fan speed. Open the windows as necessary.

3. In heavy traffic, let the engine idle in N (Neutral)

while stopped. If it is safe to do so, pull off the road, shift to P (Park) or N (Neutral) and let the engine idle.

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If the temperature overheat gage is no longer in the overheat zone or an overheat warning no longer displays, the vehicle can be driven. Continue to drive the vehicle slow for about 10 minutes. Keep a safe vehicle distance from the car in front of you. If the warning does not come back on, continue to drive normally. If the warning continues, pull over, stop, and park the vehicle right away. If there is still no sign of steam, push down the accelerator until the engine speed is about twice as fast as normal idle speed for at least three minutes while you are parked. If you still have the warning, turn off the engine until it cools down. You may decide not to lift the hood but to get service help right away.

Engine Fan Noise Your vehicle has a clutched engine cooling fan. When the clutch is engaged, the fan spins faster to provide more air to cool the engine. In most everyday driving conditions, the fan is spinning slower and the clutch is not fully engaged. This improves fuel economy and reduces fan noise. Under heavy vehicle loading, trailer towing, and/ or high outside temperatures, the fan speed increases as the clutch more fully engages, so you may hear an increase in fan noise. This is normal and should not be mistaken as the transmission slipping or making extra shifts. It is merely the cooling system functioning properly. The fan will slow down when additional cooling is not required and the clutch partially disengages. You may also hear this fan noise when you start the engine. It will go away as the fan clutch partially disengages.

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Power Steering Fluid

The power steering fluid reservoir is located in the engine compartment on the driver’s side of the vehicle. See Engine Compartment Overview on page 6-14 for reservoir location.

When to Check Power Steering Fluid It is not necessary to regularly check power steering fluid unless you suspect there is a leak in the system or you hear an unusual noise. A fluid loss in this system could indicate a problem. Have the system inspected and repaired.

How to Check Power Steering Fluid To check the power steering fluid, do the following: 1. Turn the key off and let the engine compartment

cool down.

2. Wipe the cap and the top of the reservoir clean. 3. Unscrew the cap and wipe the dipstick with a

clean rag.

4. Replace the cap and completely tighten it. 5. Then remove the cap again and look at the fluid

level on the dipstick.

The level should be at the COLD FILL mark. If necessary, add only enough fluid to bring the level up to the mark. To prevent contamination of brake fluid, never check or fill the power steering reservoir with the brake master cylinder cover off. What to Use To determine what kind of fluid to use, see Recommended Fluids and Lubricants on page 7-12. Always use the proper fluid. Failure to use the proper fluid can cause leaks and damage hoses and seals.

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Windshield Washer Fluid What to Use When you need windshield washer fluid, be sure to read the manufacturer’s instructions before use. If you will be operating your vehicle in an area where the temperature may fall below freezing, use a fluid that has sufficient protection against freezing. Adding Washer Fluid

Open the cap with the washer symbol on it. Add washer fluid until the tank is full. See Engine Compartment Overview on page 6-14 for reservoir location.

Notice: (cid:129) When using concentrated washer fluid, follow the

manufacturer’s instructions for adding water.

(cid:129) Do not mix water with ready-to-use washer fluid.

Water can cause the solution to freeze and damage your washer fluid tank and other parts of the washer system. Also, water does not clean as well as washer fluid. Fill the washer fluid tank only three-quarters full when it is very cold. This allows for fluid expansion if freezing occurs, which could damage the tank if it is completely full.

(cid:129) Do not use engine coolant (antifreeze) in your windshield washer. It can damage the vehicle’s windshield washer system and paint.

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(cid:129) Brakes Brake Fluid

The brake master cylinder reservoir is filled with DOT 3 brake fluid. See Engine Compartment Overview on page 6-14 for the location of the reservoir.

There are only two reasons why the brake fluid level in the reservoir might go down: • The brake fluid level goes down because of normal

brake lining wear. When new linings are installed, the fluid level goes back up.

• A fluid leak in the brake hydraulic system can also

cause a low fluid level. Have the brake hydraulic system fixed, since a leak means that sooner or later the brakes will not work well.

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Do not top off the brake fluid. Adding fluid does not correct a leak. If fluid is added when the linings are worn, there will be too much fluid when new brake linings are installed. Add or remove brake fluid, as necessary, only when work is done on the brake hydraulic system.

{ WARNING:

If too much brake fluid is added, it can spill on the engine and/or fuel operated heater parts, if equipped. If the vehicle has a diesel engine and a fuel operated heater, see “Fuel Operated Heater (FOH)” in the diesel engine supplement. The fluid will burn if the engine is hot enough. You or others could be burned, and the vehicle could be damaged. Add brake fluid only when work is done on the brake hydraulic system. See “Checking Brake Fluid” in this section.

Refer to the Maintenance Schedule to determine when to check the brake fluid. See Scheduled Maintenance on page 7-3.

Checking Brake Fluid Check brake fluid by looking at the brake fluid reservoir. See Engine Compartment Overview on page 6-14.

{ WARNING:

The fluid level should be above MIN. If it is not, have the brake hydraulic system checked to see if there is a leak.

After work is done on the brake hydraulic system, make sure the level is above the MIN but not over the MAX mark. What to Add Use only new DOT 3 brake fluid from a sealed container. See Recommended Fluids and Lubricants on page 7-12. Always clean the brake fluid reservoir cap and the area around the cap before removing it. This helps keep dirt from entering the reservoir.

With the wrong kind of fluid in the brake hydraulic system, the brakes might not work well. This could cause a crash. Always use the proper brake fluid.

Notice: (cid:129) Using the wrong fluid can badly damage brake

hydraulic system parts. For example, just a few drops of mineral-based oil, such as engine oil, in the brake hydraulic system can damage brake hydraulic system parts so badly that they will have to be replaced. Do not let someone put in the wrong kind of fluid. If brake fluid is spilled on the vehicle’s painted surfaces, the paint finish can be damaged. Be careful not to spill brake fluid on the vehicle. If you do, wash it off immediately. See Washing Your Vehicle on page 6-105.

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(cid:129) Brake Wear This vehicle has disc brakes. Disc brake pads have built-in wear indicators that make a high-pitched warning sound when the brake pads are worn and new pads are needed. The sound can come and go or be heard all the time the vehicle is moving, except when applying the brake pedal firmly.

{ WARNING:

The brake wear warning sound means that soon the brakes will not work well. That could lead to an accident. When the brake wear warning sound is heard, have the vehicle serviced.

Notice: Continuing to drive with worn-out brake pads could result in costly brake repair.

Some driving conditions or climates can cause a brake squeal when the brakes are first applied or lightly applied. This does not mean something is wrong with the brakes. Properly torqued wheel nuts are necessary to help prevent brake pulsation. When tires are rotated, inspect brake pads for wear and evenly tighten wheel nuts in the proper sequence to torque specifications in Capacities and Specifications on page 6-116. Brake linings should always be replaced as complete axle sets. Brake Pedal Travel See your dealer/retailer if the brake pedal does not return to normal height, or if there is a rapid increase in pedal travel. This could be a sign that brake service might be required. Brake Adjustment Every brake stop, the brakes adjust for wear.

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Replacing Brake System Parts The braking system on a vehicle is complex. Its many parts have to be of top quality and work well together if the vehicle is to have really good braking. The vehicle was designed and tested with top-quality brake parts. When parts of the braking system are replaced — for example, when the brake linings wear down and new ones are installed — be sure to get new approved replacement parts. If this is not done, the brakes might not work properly. For example, if someone puts in brake linings that are wrong for the vehicle, the balance between the front and rear brakes can change — for the worse. The braking performance expected can change in many other ways if the wrong replacement brake parts are installed.

Battery Refer to the replacement number on the original battery label when a new battery is needed. See Engine Compartment Overview on page 6-14 for battery location.

{ DANGER:

Battery posts, terminals, and related accessories contain lead and lead compounds, chemicals known to the State of California to cause cancer and reproductive harm. Wash hands after handling.

6-43

Vehicle Storage

{ WARNING:

Batteries have acid that can burn you and gas that can explode. You can be badly hurt if you are not careful. See Jump Starting on page 6-44 for tips on working around a battery without getting hurt.

Infrequent Usage: Remove the black, negative (−) cable from the battery to keep the battery from running down. Extended Storage: Remove the black, negative (−) cable from the battery or use a battery trickle charger.

Jump Starting If the vehicle battery has run down, you may want to use another vehicle and some jumper cables to start your vehicle. Be sure to use the following steps to do it safely.

{ WARNING:

Batteries can hurt you. They can be dangerous because:

• They contain acid that can burn you. • They contain gas that can explode or ignite. • They contain enough electricity to burn you. If you do not follow these steps exactly, some or all of these things can hurt you.

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Ignoring these steps could result in costly

Notice: damage to the vehicle that would not be covered by the warranty. Trying to start the vehicle by pushing or pulling it will not work, and it could damage the vehicle. 1. Check the other vehicle. It must have a 12-volt

battery with a negative ground system.

If the other vehicle’s system is not a 12-volt

Notice: system with a negative ground, both vehicles can be damaged. Only use vehicles with 12-volt systems with negative grounds to jump start your vehicle. 2. Get the vehicles close enough so the jumper cables can reach, but be sure the vehicles are not touching each other. If they are, it could cause a ground connection you do not want. You would not be able to start your vehicle, and the bad grounding could damage the electrical systems.

To avoid the possibility of the vehicles rolling, set the parking brake firmly on both vehicles involved in the jump start procedure. Put an automatic transmission in P (Park) or a manual transmission in N (Neutral) before setting the parking brake.

Notice: If you leave the radio or other accessories on during the jump starting procedure, they could be damaged. The repairs would not be covered by the warranty. Always turn off the radio and other accessories when jump starting the vehicle. 3. Turn off the ignition on both vehicles. Unplug

unnecessary accessories plugged into the cigarette lighter or the accessory power outlet. Turn off the radio and all lamps that are not needed. This will avoid sparks and help save both batteries. And it could save the radio!

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4. Open the hoods and locate the positive (+) and

negative (−) terminal locations of the other vehicle. Your vehicle has a remote positive (+) jump starting terminal and a remote negative (−) jump starting terminal. You should always use these remote terminals instead of the terminals on the battery. The remote positive (+) terminal is located behind a red plastic cover near the engine accessory drive bracket on the driver’s side of the engine compartment, below the alternator. To uncover the remote positive (+) terminal, open the red plastic cover. The remote negative (−) terminal is located on the engine drive bracket on all V8 engines and is marked GND (Ground). On V6 engines the remote negative (−) terminal is located on a tab attached to the engine accessory drive bracket and is marked GND (Ground).

{ WARNING:

Using an open flame near a battery can cause battery gas to explode. People have been hurt doing this, and some have been blinded. Use a flashlight if you need more light. Be sure the battery has enough water. You do not need to add water to the battery installed in your new vehicle. But if a battery has filler caps, be sure the right amount of fluid is there. If it is low, add water to take care of that first. If you do not, explosive gas could be present. Battery fluid contains acid that can burn you. Do not get it on you. If you accidentally get it in your eyes or on your skin, flush the place with water and get medical help immediately.

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{ WARNING:

Fans or other moving engine parts can injure you badly. Keep your hands away from moving parts once the engine is running.

5. Check that the jumper cables do not have loose or missing insulation. If they do, you could get a shock. The vehicles could be damaged too. Before you connect the cables, here are some basic things you should know. Positive (+) will go to positive (+) or to a remote positive (+) terminal if the vehicle has one. Negative (−) will go to a heavy, unpainted metal engine part or to a remote negative (−) terminal if the vehicle has one. Do not connect positive (+) to negative (−) or you will get a short that would damage the battery and maybe other parts too. And do not connect the negative (−) cable to the negative (−) terminal on the dead battery because this can cause sparks.

6. Connect the red positive (+) cable to the positive (+)

terminal of the dead battery. Use a remote positive (+) terminal if the vehicle has one.

7. Do not let the other end touch metal. Connect it to the positive (+) terminal of the good battery. Use a remote positive (+) terminal if the vehicle has one.

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8. Now connect the black negative (−) cable to the negative (−) terminal of the good battery. Use a remote negative (−) terminal if the vehicle has one. Do not let the other end touch anything until the next step. The other end of the negative (−) cable does not go to the dead battery. It goes to a heavy, unpainted metal engine part or to a remote negative (−) terminal on the vehicle with the dead battery.

9. Connect the other end of the negative (−) cable to

the negative (−) terminal location on the vehicle with the dead battery. Your vehicle has a remote negative (−) terminal for this purpose. It is marked GND.

10. Now start the vehicle with the good battery and run

the engine for a while.

11. Try to start the vehicle that had the dead battery.

If it will not start after a few tries, it probably needs service.

If the jumper cables are connected or

Notice: removed in the wrong order, electrical shorting may occur and damage the vehicle. The repairs would not be covered by the vehicle warranty. Always connect and remove the jumper cables in the correct order, making sure that the cables do not touch each other or other metal.

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Jumper Cable Removal

A. Heavy, Unpainted Metal Engine Part or Remote

Negative (−) Terminal

B. Good Battery or Remote Positive (+) and Remote

Negative (−) Terminals

C. Dead Battery or Remote Positive (+) Terminal

To disconnect the jumper cables from both vehicles, do the following: 1. Disconnect the black negative (−) cable from the

vehicle that had the dead battery.

2. Disconnect the black negative (−) cable from the

vehicle with the good battery.

3. Disconnect the red positive (+) cable from the

vehicle with the good battery.

4. Disconnect the red positive (+) cable from the other

vehicle.

5. Return the remote positive (+) terminal cover to its

original position.

All-Wheel Drive Lubricant checks in this section also apply to these vehicles. However, there are two additional systems that need lubrication. Transfer Case When to Check Lubricant Refer to the Maintenance Schedule to determine how often to check the lubricant. See Scheduled Maintenance on page 7-3.

How to Check Lubricant To get an accurate reading, the vehicle should be on a level surface.

If the level is below the bottom of the filler plug hole, you’ll need to add some lubricant. Add enough lubricant to raise the level to the bottom of the filler plug hole. Use care not to overtighten the plug. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 7-12.

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Rear Axle When to Check Lubricant Refer to the Maintenance Schedule to determine how often to check the lubricant. See Scheduled Maintenance on page 7-3. How to Check Lubricant

To get an accurate reading, the vehicle should be on a level surface.

6-50

If you have the 1500 Series, the proper level is from 5/8 inch (15 mm) to 1 5/8 inch (40 mm) below the bottom of the filler plug hole. The proper level for the 2500 and 3500 Series is from 0 to 1/4 (6 mm) below the bottom of the filler plug hole. Add only enough fluid to reach the proper level. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 7-12. Front Axle When to Check and Change Lubricant Refer to the Maintenance Schedule to determine how often to check the lubricant and when to change it. See Scheduled Maintenance on page 7-3. How to Check Lubricant To get an accurate reading, the vehicle should be on a level surface.

If the level is below the bottom of the filler plug hole, you may need to add some lubricant.

When the differential is cold, add enough lubricant to raise the level to 3/8 inch (10 mm) below the filler plug hole. When the differential is at operating temperature (warm), add enough lubricant to raise the level to the bottom of the filler plug hole. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 7-12.

Noise Control System Tampering with Noise Control System Prohibited The following information relates to compliance with federal noise emission standards for vehicles with a Gross Vehicle Weight Rating (GVWR) of more than 10,000 lbs (4 536 kg). The Maintenance Schedule provides information on maintaining the noise control system to minimize degradation of the noise emission control system during the life of your vehicle. The noise control system warranty is given in your warranty booklet. These standards apply only to vehicles sold in the United States. Federal law prohibits the following acts or the causing thereof: 1. The removal or rendering inoperative by any person,

other than for purposes of maintenance, repair or replacement, of any device or element of design incorporated into any new vehicle for the purpose of noise control, prior to its sale or delivery to the ultimate purchaser or while it is in use; or

2. The use of the vehicle after such device or element of design has been removed or rendered inoperative by any person.

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Among those acts presumed to constitute tampering are the acts listed below. Insulation: • Removal of the noise shields or any underhood

insulation.

Engine: • Removal or rendering engine speed governor, if the

vehicle has one, inoperative so as to allow engine speed to exceed manufacturer specifications.

Fan and Drive: • Removal of fan clutch, if the vehicle has one, or

rendering clutch inoperative.

• Removal of the fan shroud, if the vehicle has one.

Air Intake: • Removal of the air cleaner silencer. • Modification of the air cleaner. Exhaust: • Removal of the muffler and/or resonator. • Removal of the exhaust pipes and exhaust pipe

clamps.

Fuel Operated Heater (FOH) — Diesel Engine: • Removal of the muffler.

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Headlamps To remove the headlamp assembly from the vehicle and access the bulbs: 1. Open the hood. See Hood Release on page 6-13

for more information.

2. Remove the two bolts from the headlamp assembly.

Bulb Replacement For the proper type of replacement bulbs, see Replacement Bulbs on page 6-58. For any bulb changing procedure not listed in this section, contact your dealer/retailer.

Halogen Bulbs

{ WARNING:

Halogen bulbs have pressurized gas inside and can burst if you drop or scratch the bulb. You or others could be injured. Be sure to read and follow the instructions on the bulb package.

3. Remove the two pins on the top of the headlamp assembly. To remove the pins, turn the outer pin clockwise and pull it straight up. To remove the inner pin, turn it counterclockwise and pull it straight up.

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4. Lift the inboard side of the headlamp to release the

inboard tab from the radiator support.

5. Lift the outboard side of the headlamp to release

the outboard tab from the radiator support.

6. Lower the headlamp to allow the vertical adjustor to

clear the tie bar.

7. Turn the headlamp forward and upward to remove

it from the grille.

8. Turn the bulb connector counterclockwise and pull it

out of the housing.

9. Without removing the headlamp assembly itself,

remove the bulb socket from the back of the headlamp on the driver’s side.

10. Turn the bulb counterclockwise one quarter turn to

remove it from the socket.

11. On the passenger’s side, turn the bulb clockwise

one turn.

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12. Install the new bulb into the socket then reinstall it

into the headlamp assembly.

13. Reverse the steps to reinstall the headlamp

assembly.

Front Turn Signal, Sidemarker and Parking Lamps To replace the front turn signal, sidemarker and/or parking lamp bulb(s):

3. Remove the lamp from the grille. 4. Squeeze the tab on the side of the bulb socket

while turning it counterclockwise.

5. Remove the bulb socket from the back of the lamp

assembly.

6. Replace the bulb. 7. Turn the bulb socket clockwise to reinstall it in the

lamp assembly.

1. Use a small tool to unlatch the outboard clip on

the lamp.

2. Pull the lamp forward to completely unlatch the clip.

Move the lamp to the outboard side to loosen the tabs.

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Center High-Mounted Stoplamp (CHMSL) The Center High-Mounted Stoplamp (CHMSL) is located above the rear doors at the center of the vehicle. To replace a bulb:

Taillamps To replace one of these bulbs:

1. Remove the two

inboard nuts from the inside of the taillamp assembly.

1. Remove the two screws from the CHMSL assembly. 2. Remove the CHMSL assembly. 3. Turn the bulb counterclockwise one quarter turn to

remove it from the socket.

4. Turn the bulb clockwise one quarter turn to install it

in the socket.

5. Reinstall the CHMSL assembly and two screws. Do not block or damage the CHMSL when items are loaded on the roof of the vehicle.

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2. Pull the taillamp assembly straight back to clear

the studs.

3. Slide the taillamp assembly slightly upward to

release the lower clip.

4. Remove the three nuts on the taillamp assembly. 5. Remove the taillamp assembly from the vehicle.

6. Remove the bulb socket by squeezing the

tab on the side of the socket while turning it counterclockwise.

7. Turn the bulb counterclockwise to remove it. 8. Turn the bulb clockwise to install it in the socket. 9. Reinstall the bulb socket by squeezing the tab while

turning it clockwise.

10. Reinstall the taillamp assembly and three nuts on

the vehicle.

11. Slide the taillamp slightly downward to reengage

the lower clip.

12. Push the taillamp straight forward to reengage the

studs.

13. Reinstall the two inboard nuts from the inside of the

taillamp assembly.

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License Plate Lamp To replace one of these bulbs:

A. Bulb Socket B. License Plate Bulb Assembly C. Screws 1. Remove the two screws (C) securing the license

plate bulb assembly (B).

2. Turn the bulb socket (A) counterclockwise and pull

the bulb straight out of the socket.

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3. Install the new bulb. 4. Reverse steps 1 and 2 to reinstall the license plate

bulb assembly.

Replacement Bulbs

Exterior Lamp

Bulb Number

Back-up, Rear Parking, Stoplamp, and Turn Signal Lamp

Center High Mounted Stop Lamp (CHMSL)

Front Parking and Turn Signal Lamp

Front Sidemarker Lamp

License Plate Lamp

Headlamps

Composite High-Beam Headlamp

Composite Low-Beam Headlamp

Sealed Beam Headlamp

3157

912

3157KX

194

194

9005

9006GS

H6054

For replacement bulbs not listed here, contact your dealer/retailer.

Windshield Wiper Blade Replacement Windshield wiper blades should be inspected for wear and cracking. See Scheduled Maintenance on page 7-3
for more information on wiper blade inspection. Replacement blades come in different types and are removed in different ways. To remove the type with a release clip, do the following: 1. Lift the wiper arm until it locks into a vertical

position.

3. The insert has two notches at one end that are locked by bottom claws of the blade assembly. At the notched end, pull the insert from the blade assembly.

4. To install the new wiper insert, slide the notched end last, into the end with two blade claws. Then slide the insert all the way through the blade claws at the opposite end.

5. Make sure that the notches are locked by the bottom claws. Make sure that all other claws are properly locked on both sides of the insert slot. 6. Put the blade assembly pivot in the wiper arm hook.

Pull it up until the pivot locking tab locks in the hook slot.

7. Carefully lower the wiper arm and blade assembly

into the windshield.

2. Press down on the blade assembly pivot locking

tab. Pull down on the blade assembly to release it from the wiper arm hook.

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WARNING:

(Continued)

• Underinflated tires pose the same danger as overloaded tires. The resulting accident could cause serious injury. Check all tires frequently to maintain the recommended pressure. Tire pressure should be checked when your vehicle’s tires are cold. See Inflation - Tire Pressure on page 6-68.

• Overinflated tires are more likely to be cut, punctured, or broken by a sudden impact — such as when you hit a pothole. Keep tires at the recommended pressure.

• Worn, old tires can cause accidents.

If the tire’s tread is badly worn, or if your vehicle’s tires have been damaged, replace them.

Tires Your new vehicle comes with high-quality tires made by a leading tire manufacturer. If you ever have questions about your tire warranty and where to obtain service, see your vehicle Warranty booklet for details. For additional information refer to the tire manufacturer.

{ WARNING:

Poorly maintained and improperly used tires are dangerous.

• Overloading your vehicle’s tires can cause overheating as a result of too much flexing. You could have an air-out and a serious accident. See Loading the Vehicle on page 5-19.

WARNING:

(Continued)

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Tire Sidewall Labeling Useful information about a tire is molded into the sidewall. The following illustrations are examples of a typical P-Metric and a LT-Metric tire sidewall.

Passenger (P-Metric) Tire

(A) Tire Size: The tire size code is a combination of letters and numbers used to define a particular tire’s width, height, aspect ratio, construction type, and service description. See the “Tire Size” illustration later in this section for more detail.

(B) TPC Spec (Tire Performance Criteria Specification): Original equipment tires designed to GM’s specific tire performance criteria have a TPC specification code molded onto the sidewall. GM’s TPC specifications meet or exceed all federal safety guidelines. (C) DOT (Department of Transportation): The Department of Transportation (DOT) code indicates that the tire is in compliance with the U.S. Department of Transportation Motor Vehicle Safety Standards. (D) Tire Identification Number (TIN): The letters and numbers following DOT code are the Tire Identification Number (TIN). The TIN shows the manufacturer and plant code, tire size, and date the tire was manufactured. The TIN is molded onto both sides of the tire, although only one side may have the date of manufacture. (E) Tire Ply Material: The type of cord and number of plies in the sidewall and under the tread. (F) Uniform Tire Quality Grading (UTQG): Tire manufacturers are required to grade tires based on three performance factors: treadwear, traction, and temperature resistance. For more information, see Uniform Tire Quality Grading on page 6-81.

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(G) Maximum Cold Inflation Load Limit: Maximum load that can be carried and the maximum pressure needed to support that load. For information on recommended tire pressure see Inflation - Tire Pressure on page 6-68
and Loading the Vehicle on page 5-19.

Light Truck (LT-Metric) Tire

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(A) Tire Size: The tire size code is a combination of letters and numbers used to define a particular tire’s width, height, aspect ratio, construction type, and service description. See the “Tire Size” illustration later in this section for more detail. (B) TPC Spec (Tire Performance Criteria Specification): Original equipment tires designed to GM’s specific tire performance criteria have a TPC specification code molded onto the sidewall. GM’s TPC specifications meet or exceed all federal safety guidelines. This does not apply to Goodyear LT225/75R16 G949 RSA and Goodyear LT225/ 75R16 G933 RSD commercial truck tires. (C) Dual Tire Maximum Load: Maximum load that can be carried and the maximum pressure needed to support that load when used in a dual configuration. For information on recommended tire pressure see Inflation - Tire Pressure on page 6-68 and Loading the Vehicle on page 5-19. (D) DOT (Department of Transportation): The Department of Transportation (DOT) code indicates that the tire is in compliance with the U.S. Department of Transportation Motor Vehicle Safety Standards.

(E) Tire Identification Number (TIN): The letters and numbers following DOT code are the Tire Identification Number (TIN). The TIN shows the manufacturer and plant code, tire size, and date the tire was manufactured. The TIN is molded onto both sides of the tire, although only one side may have the date of manufacture. (F) Tire Ply Material: The type of cord and number of plies in the sidewall and under the tread. (G) Single Tire Maximum Load: Maximum load that can be carried and the maximum pressure needed to support that load when used as a single. For information on recommended tire pressure see Inflation - Tire Pressure on page 6-68 and Loading the Vehicle on page 5-19.

Tire Size The following examples show the different parts of a tire size.

Passenger (P-Metric) Tire

(A) Passenger (P-Metric) Tire: The United States version of a metric tire sizing system. The letter P as the first character in the tire size means a passenger vehicle tire engineered to standards set by the U.S. Tire and Rim Association. (B) Tire Width: The three-digit number indicates the tire section width in millimeters from sidewall to sidewall.

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(C) Aspect Ratio: A two-digit number that indicates the tire height-to-width measurements. For example, if the tire size aspect ratio is 75, as shown in item C of the illustration, it would mean that the tire’s sidewall is 75 percent as high as it is wide. (D) Construction Code: A letter code is used to indicate the type of ply construction in the tire. The letter R means radial ply construction; the letter D means diagonal or bias ply construction; and the letter B means belted-bias ply construction. (E) Rim Diameter: Diameter of the wheel in inches. (F) Service Description: These characters represent the load index and speed rating of the tire. The load index represents the load carry capacity a tire is certified to carry. The speed rating is the maximum speed a tire is certified to carry a load.

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Light Truck (LT-Metric) Tire

(A) Light Truck (LT-Metric) Tire: The United States version of a metric tire sizing system. The letters LT as the first two characters in the tire size means a light truck tire engineered to standards set by the U.S. Tire and Rim Association. (B) Tire Width: The three-digit number indicates the tire section width in millimeters from sidewall to sidewall. (C) Aspect Ratio: A two-digit number that indicates the tire height-to-width measurements. For example, if the tire size aspect ratio is 75, as shown in item C of the light truck (LT-Metric) tire illustration, it would mean that the tire’s sidewall is 75 percent as high as it is wide.

(D) Construction Code: A letter code is used to indicate the type of ply construction in the tire. The letter R means radial ply construction; the letter D means diagonal or bias ply construction; and the letter B means belted-bias ply construction. (E) Rim Diameter: Diameter of the wheel in inches. (F) Load Range: Load Range. (G) Service Description: The service description indicates the load index and speed rating of a tire. If two numbers are given as in the example, 120/116, then this represents the load index for single versus dual wheel usage (single/dual). The speed rating is the maximum speed a tire is certified to carry a load. This does not apply to Goodyear LT225/75R16 G949 RSA and Goodyear LT225/75R16 G933 RSD commercial truck tires; see the dual tire and single tire maximum load and load range letter designations on the tire sidewall.

Tire Terminology and Definitions

Air Pressure: The amount of air inside the tire pressing outward on each square inch of the tire. Air pressure is expressed in pounds per square inch (psi) or kilopascal (kPa). Accessory Weight: This means the combined weight of optional accessories. Some examples of optional accessories are, automatic transmission, power steering, power brakes, power windows, power seats, and air conditioning. Aspect Ratio: The relationship of a tire’s height to its width. Belt: A rubber coated layer of cords that is located between the plies and the tread. Cords may be made from steel or other reinforcing materials. Bead: The tire bead contains steel wires wrapped by steel cords that hold the tire onto the rim. Bias Ply Tire: A pneumatic tire in which the plies are laid at alternate angles less than 90 degrees to the centerline of the tread.

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Cold Tire Pressure: The amount of air pressure in a tire, measured in pounds per square inch (psi) or kilopascals (kPa) before a tire has built up heat from driving. See Inflation - Tire Pressure on page 6-68. Curb Weight: The weight of a motor vehicle with standard and optional equipment including the maximum capacity of fuel, oil, and coolant, but without passengers and cargo. DOT Markings: A code molded into the sidewall of a tire signifying that the tire is in compliance with the U.S. Department of Transportation (DOT) motor vehicle safety standards. The DOT code includes the Tire Identification Number (TIN), an alphanumeric designator which can also identify the tire manufacturer, production plant, brand, and date of production. GVWR: Gross Vehicle Weight Rating. See Loading the Vehicle on page 5-19. GAWR FRT: Gross Axle Weight Rating for the front axle. See Loading the Vehicle on page 5-19. GAWR RR: Gross Axle Weight Rating for the rear axle. See Loading the Vehicle on page 5-19.

Intended Outboard Sidewall: The side of an asymmetrical tire, that must always face outward when mounted on a vehicle. Kilopascal (kPa): The metric unit for air pressure. Light Truck (LT-Metric) Tire: A tire used on light duty trucks and some multipurpose passenger vehicles. Load Index: An assigned number ranging from 1
to 279 that corresponds to the load carrying capacity of a tire. Maximum Inflation Pressure: The maximum air pressure to which a cold tire can be inflated. The maximum air pressure is molded onto the sidewall. Maximum Load Rating: The load rating for a tire at the maximum permissible inflation pressure for that tire. Maximum Loaded Vehicle Weight: The sum of curb weight, accessory weight, vehicle capacity weight, and production options weight. Normal Occupant Weight: The number of occupants a vehicle is designed to seat multiplied by 150 lbs (68 kg). See Loading the Vehicle on page 5-19.

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Occupant Distribution: Designated seating positions. Outward Facing Sidewall: The side of an asymmetrical tire that has a particular side that faces outward when mounted on a vehicle. The side of the tire that contains a whitewall, bears white lettering, or bears manufacturer, brand, and/or model name molding that is higher or deeper than the same moldings on the other sidewall of the tire. Passenger (P-Metric) Tire: A tire used on passenger cars and some light duty trucks and multipurpose vehicles. Recommended Inflation Pressure: Vehicle manufacturer’s recommended tire inflation pressure as shown on the tire placard. See Inflation - Tire Pressure on page 6-68
and Loading the Vehicle on page 5-19. Radial Ply Tire: A pneumatic tire in which the ply cords that extend to the beads are laid at 90 degrees to the centerline of the tread. Rim: A metal support for a tire and upon which the tire beads are seated. Sidewall: The portion of a tire between the tread and the bead.

Speed Rating: An alphanumeric code assigned to a tire indicating the maximum speed at which a tire can operate. Traction: The friction between the tire and the road surface. The amount of grip provided. Tread: The portion of a tire that comes into contact with the road. Treadwear Indicators: Narrow bands, sometimes called wear bars, that show across the tread of a tire when only 1/16 inch (1.6 mm) of tread remains. See When It Is Time for New Tires on page 6-78. UTQGS (Uniform Tire Quality Grading Standards): A tire information system that provides consumers with ratings for a tire’s traction, temperature, and treadwear. Ratings are determined by tire manufacturers using government testing procedures. The ratings are molded into the sidewall of the tire. See Uniform Tire Quality Grading on page 6-81. Vehicle Capacity Weight: The number of designated seating positions multiplied by 150 lbs (68 kg) plus the rated cargo load. See Loading the Vehicle on page 5-19.

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If your tires have too much air (over-inflation), you can get the following: (cid:129) Unusual wear (cid:129) Poor handling (cid:129) Rough ride (cid:129) Needless damage from road hazards A vehicle specific Tire and Loading Information label is attached to your vehicle. This label shows your vehicle’s original equipment tires and the correct inflation pressures for your tires when they are cold. The recommended cold tire inflation pressure, shown on the label, is the minimum amount of air pressure needed to support your vehicle’s maximum load carrying capacity. For additional information regarding how much weight your vehicle can carry, and an example of the Tire and Loading Information label, see Loading the Vehicle on page 5-19. How you load your vehicle affects vehicle handling and ride comfort. Never load your vehicle with more weight than it was designed to carry.

Vehicle Maximum Load on the Tire: Load on an individual tire due to curb weight, accessory weight, occupant weight, and cargo weight. Vehicle Placard: A label permanently attached to a vehicle showing the vehicle’s capacity weight and the original equipment tire size and recommended inflation pressure. See “Tire and Loading Information Label” under Loading the Vehicle on page 5-19.

Inflation - Tire Pressure Tires need the correct amount of air pressure to operate effectively. Notice: Do not let anyone tell you that under-inflation or over-inflation is all right. It is not. If your tires do not have enough air (under-inflation), you can get the following: (cid:129) Too much flexing (cid:129) Too much heat (cid:129) Tire overloading (cid:129) Premature or irregular wear (cid:129) Poor handling (cid:129) Reduced fuel economy

6-68

When to Check Check your tires once a month or more. Do not forget to check the pressure of the spare tire. See Spare Tire on page 6-101 for additional information. How to Check Use a good quality pocket-type gage to check tire pressure. You cannot tell if your tires are properly inflated simply by looking at them. Radial tires may look properly inflated even when they are underinflated. Check the tire’s inflation pressure when the tires are cold. Cold means your vehicle has been sitting for at least three hours or driven no more than 1 mile (1.6 km).

Remove the valve cap from the tire valve stem. Press the tire gage firmly onto the valve to get a pressure measurement. If the cold tire inflation pressure matches the recommended pressure on the Tire and Loading Information label, no further adjustment is necessary. If the pressure is low, add air until you reach the recommended amount. If you overfill the tire, release air by pushing on the metal stem in the center of the tire valve. Recheck the tire pressure with the tire gage. Be sure to put the valve caps back on the valve stems. They help prevent leaks by keeping out dirt and moisture.

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Tire Pressure Monitor System The Tire Pressure Monitor System (TPMS) uses radio and sensor technology to check tire pressure levels. The TPMS sensors monitor the air pressure in your vehicle’s tires and transmit tire pressure readings to a receiver located in the vehicle. Each tire, including the spare (if provided), should be checked monthly when cold and inflated to the inflation pressure recommended by the vehicle manufacturer on the vehicle placard or tire inflation pressure label. (If your vehicle has tires of a different size than the size indicated on the vehicle placard or tire inflation pressure label, you should determine the proper tire inflation pressure for those tires.) As an added safety feature, your vehicle has been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pressure telltale when one or more of your tires is significantly under-inflated.

Dual Tire Operation When the vehicle is new, or whenever a wheel, wheel bolt or wheel nut is replaced, check the wheel nut torque after 100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km) of driving. For proper wheel nut tightening information, see “Removing the Flat Tire and Installing the Spare Tire” later in this section, under Changing a Flat Tire on page 6-86. Also see “Wheel Nut Torque” under Capacities and Specifications on page 6-116. The outer tire on a dual wheel setup generally wears faster than the inner tire. Your tires will wear more evenly and last longer if you rotate the tires periodically. See Tire Inspection and Rotation on page 6-75. Also see Scheduled Maintenance on page 7-3.

{ WARNING:

If you operate your vehicle with a tire that is badly underinflated, the tire can overheat. An overheated tire can lose air suddenly or catch fire. You or others could be injured. Be sure all tires (including the spare) are properly inflated.

See Tires on page 6-60 and Inflation - Tire Pressure on page 6-68 for more information on proper tire inflation.

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Accordingly, when the low tire pressure telltale illuminates, you should stop and check your tires as soon as possible, and inflate them to the proper pressure. Driving on a significantly under-inflated tire causes the tire to overheat and can lead to tire failure. Under-inflation also reduces fuel efficiency and tire tread life, and may affect the vehicle’s handling and stopping ability. Please note that the TPMS is not a substitute for proper tire maintenance, and it is the driver’s responsibility to maintain correct tire pressure, even if under-inflation has not reached the level to trigger illumination of the TPMS low tire pressure telltale. Your vehicle has also been equipped with a TPMS malfunction indicator to indicate when the system is not operating properly. The TPMS malfunction indicator is combined with the low tire pressure telltale. When the system detects a malfunction, the telltale will flash for approximately one minute and then remain continuously illuminated. This sequence will continue upon subsequent vehicle start-ups as long as the malfunction exists.

When the malfunction indicator is illuminated, the system may not be able to detect or signal low tire pressure as intended. TPMS malfunctions may occur for a variety of reasons, including the installation of replacement or alternate tires or wheels on the vehicle that prevent the TPMS from functioning properly. Always check the TPMS malfunction telltale after replacing one or more tires or wheels on your vehicle to ensure that the replacement or alternate tires and wheels allow the TPMS to continue to function properly. See Tire Pressure Monitor Operation on page 6-72 for additional information. Federal Communications Commission (FCC) and Industry and Science Canada See Radio Frequency Statement on page 8-20
for information regarding Part 15 of the Federal Communications Commission (FCC) Rules and RSS-210/211 of Industry and Science Canada.

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Tire Pressure Monitor Operation This vehicle may have a Tire Pressure Monitor System (TPMS). The TPMS is designed to warn the driver when a low tire pressure condition exists. TPMS sensors are mounted onto each tire and wheel assembly, excluding the spare tire and wheel assembly. The TPMS sensors monitor the air pressure in the vehicle’s tires and transmits the tire pressure readings to a receiver located in the vehicle.

When a low tire pressure condition is detected, the TPMS will illuminate the low tire pressure warning symbol located on the instrument panel cluster.

At the same time a message to check the pressure in a specific tire appears on the Driver Information Center (DIC) display. The low tire pressure warning light and the DIC warning message come on at each ignition cycle until the tires are inflated to the correct inflation pressure.

If your vehicle has DIC buttons, tire pressure levels can be viewed by the driver. For additional information and details about the DIC operation and displays see DIC Operation and Displays on page 4-37 and DIC Warnings and Messages on page 4-44. The low tire pressure warning light may come on in cool weather when the vehicle is first started, and then turn off as you start to drive. This could be an early indicator that the air pressure in the tire(s) are getting low and need to be inflated to the proper pressure. A Tire and Loading Information label, attached to your vehicle, shows the size of your vehicle’s original equipment tires and the correct inflation pressure for your vehicle’s tires when they are cold. See Loading the Vehicle on page 5-19, for an example of the Tire and Loading Information label and its location on your vehicle. Also see Inflation - Tire Pressure on page 6-68. Your vehicle’s TPMS can warn you about a low tire pressure condition but it does not replace normal tire maintenance. See Tire Inspection and Rotation on page 6-75 and Tires on page 6-60. Notice: Liquid tire sealants could damage the Tire Pressure Monitor System (TPMS) sensors. Sensor damage caused by using a tire sealant is not covered by your warranty. Do not use liquid tire sealants.

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TPMS Malfunction Light and Message The TPMS will not function properly if one or more of the TPMS sensors are missing or inoperable. When the system detects a malfunction, the low tire warning light flashes for about one minute and then stays on for the remainder of the ignition cycle. A DIC warning message is also displayed. The low tire warning light and DIC warning message come on at each ignition cycle until the problem is corrected. Some of the conditions that can cause the malfunction light and DIC message to come on are: • One of the road tires has been replaced with the spare tire. The spare tire does not have a TPMS sensor. The TPMS malfunction light and DIC message should go off once you re-install the road tire containing the TPMS sensor.

• The TPMS sensor matching process was started but

not completed or not completed successfully after rotating the vehicle’s tires. The DIC message and TPMS malfunction light should go off once the TPMS sensor matching process is performed successfully. See “TPMS Sensor Matching Process” later in this section.

• One or more TPMS sensors are missing or damaged. The DIC message and the TPMS malfunction light should go off when the TPMS sensors are installed and the sensor matching process is performed successfully. See your dealer/retailer for service.

• Replacement tires or wheels do not match your

vehicle’s original equipment tires or wheels. Tires and wheels other than those recommended for your vehicle could prevent the TPMS from functioning properly. See Buying New Tires on page 6-79.

• Operating electronic devices or being near facilities using radio wave frequencies similar to the TPMS could cause the TPMS sensors to malfunction.

If the TPMS is not functioning it cannot detect or signal a low tire condition. See your dealer/retailer for service if the TPMS malfunction light and DIC message comes on and stays on.

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TPMS Sensor Matching Process Each TPMS sensor has a unique identification code. Any time you rotate your vehicle’s tires or replace one or more of the TPMS sensors, the identification codes will need to be matched to the new tire/wheel position. The sensors are matched to the tire/wheel positions in the following order: driver side front tire, passenger side front tire, passenger side rear tire, and driver side rear tire using a TPMS diagnostic tool. See your dealer/retailer for service. The TPMS sensors can also be matched to each tire/wheel position by increasing or decreasing the tire’s air pressure. If increasing the tire’s air pressure, do not exceed the maximum inflation pressure indicated on the tire’s sidewall. To decrease air-pressure out of a tire you can use the pointed end of the valve cap, a pencil-style air pressure gage, or a key. You have two minutes to match the first tire/wheel position, and five minutes overall to match all four tire/wheel positions. If it takes longer than two minutes, to match the first tire and wheel, or more than five minutes to match all four tire and wheel positions the matching process stops and you need to start over.

The TPMS sensor matching process is outlined below: 1. Set the parking brake. 2. Turn the ignition switch to ON/RUN with the

engine off.

3. Press the Remote Keyless Entry (RKE) transmitter’s

LOCK and UNLOCK buttons at the same time for approximately five seconds. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen. If your vehicle does not have RKE, press the Driver Information Center (DIC) vehicle information button until the PRESS V TO RELEARN TIRE POSITIONS message displays. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen. If your vehicle does not have RKE or DIC buttons, press the trip odometer reset stem located on the instrument panel cluster until the PRESS V TO RELEARN TIRE POSITIONS message displays. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen.

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4. Start with the driver side front tire. 5. Remove the valve cap from the valve cap stem.

Activate the TPMS sensor by increasing or decreasing the tire’s air pressure for five seconds, or until a horn chirp sounds. The horn chirp, which may take up to 30 seconds to sound, confirms that the sensor identification code has been matched to this tire and wheel position.

6. Proceed to the passenger side front tire, and repeat

the procedure in Step 5.

7. Proceed to the passenger side rear tire, and repeat

the procedure in Step 5.

8. Proceed to the driver side rear tire, and repeat the procedure in Step 5. The horn sounds two times to indicate the sensor identification code has been matched to the driver side rear tire, and that the TPMS sensor matching process is no longer active. The TIRE LEARNING ACTIVE message on the DIC display screen goes off.

9. Turn the ignition switch to LOCK/OFF. 10. Set all four tires to the recommended air pressure

level as indicated on the Tire and Loading Information label.

11. Put the valve caps back on the valve stems.

Tire Inspection and Rotation Inspect tires regularly for signs of wear or damage. Also inspect the spare tire. For more information on tire inspection, see When It Is Time for New Tires on page 6-78. Tires should be rotated every 5,000 to 8,000 miles (8 000 to 13 000 km). See Scheduled Maintenance on page 7-3. The purpose of a regular tire rotation is to achieve a uniform wear for all tires on the vehicle. This will ensure that the vehicle continues to perform most like it did when the tires were new. The first rotation is the most important. See Scheduled Maintenance on page 7-3. Any time you notice unusual wear, rotate the tires as soon as possible and check wheel alignment. Also check for damaged tires or wheels. See When It Is Time for New Tires on page 6-78 and Wheel Replacement on page 6-82.

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Single Rear Wheels

Dual Rear Wheels

If your vehicle has single rear wheels, always use the correct rotation pattern shown here when rotating the vehicle’s tires. Do not include the spare tire in the tire rotation.

If the vehicle has dual rear wheels and the tread design for the front tires is the same as the rear tires, always use one of the correct rotation patterns shown here when rotating the tires.

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Pressure on page 6-68 and Loading the Vehicle on page 5-19. Make certain that all wheel nuts are properly tightened. See “Wheel Nut Torque” under Capacities and Specifications on page 6-116.

{ WARNING:

Rust or dirt on a wheel, or on the parts to which it is fastened, can make wheel nuts become loose after time. The wheel could come off and cause an accident. When you change a wheel, remove any rust or dirt from places where the wheel attaches to the vehicle. In an emergency, you can use a cloth or a paper towel to do this; but be sure to use a scraper or wire brush later, if needed, to get all the rust or dirt off. See Changing a Flat Tire on page 6-86.

If your vehicle has a Tire Pressure Monitor System (TPMS), reset the TPMS sensors after rotating the tires. See Tire Pressure Monitor Operation on page 6-72. Make sure the spare tire is stored securely. Push, pull, and then try to rotate or turn the tire. If it moves, tighten the cable. See Storing a Flat or Spare Tire and Tools on page 6-100.

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If the vehicle has dual rear wheels and the tread design for the front tires is different from the dual rear tires, always use the correct rotation pattern shown here when rotating the tires. The dual tires are rotated as a pair and the inside rear tires become the outside rear tires. When you install dual wheels, be sure that vent holes in the inner and outer wheels on each side are lined up. Also see Dual Tire Operation on page 6-70 for additional information. After the tires have been rotated, adjust the front and rear inflation pressures as shown on the Tire and Loading Information label. See Inflation - Tire

When It Is Time for New Tires Various factors, such as maintenance, temperatures, driving speeds, vehicle loading, and road conditions, influence when you need new tires.

One way to tell when it is time for new tires is to check the treadwear indicators, which appear when your tires have only 1/16 inch (1.6 mm) or less of tread remaining.

Some commercial truck tires, including Goodyear LT225/75R16 G949 RSA and Goodyear LT225/75R16
G933 RSD, may not have treadwear indicators. If the tires do not have treadwear indicators, replace the tires when the tread depth is down to 1/8 inch (3.2 mm) for the front tires, or 1/16 inch (1.6 mm) for the rear tires.

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You need new tires if any of the following statements are true: • You can see the indicators at three or more places

around the tire.

• You can see cord or fabric showing through the

tire’s rubber.

• The tread or sidewall is cracked, cut, or snagged

deep enough to show cord or fabric. • The tire has a bump, bulge, or split. • The tire has a puncture, cut, or other damage that

cannot be repaired well because of the size or location of the damage.

The rubber in tires degrades over time, even if they are not being used. This is also true for the spare tire, if your vehicle has one. Multiple conditions affect how fast this aging takes place, including temperatures, loading conditions, and inflation pressure maintenance. With proper care and maintenance tires will typically wear out before they degrade due to age. If you are unsure about the need to replace your tires as they get older, consult the tire manufacturer for more information.

Buying New Tires GM has developed and matched specific tires for your vehicle. The original equipment tires installed on your vehicle, when it was new, were designed to meet General Motors Tire Performance Criteria Specification (TPC spec) system rating. If you need replacement tires, GM strongly recommends that you get tires with the same TPC Spec rating. This way, your vehicle will continue to have tires that are designed to give the same performance and vehicle safety, during normal use, as the original tires. GM’s exclusive TPC Spec system considers over a dozen critical specifications that impact the overall performance of your vehicle, including brake system performance, ride and handling, traction control, and tire pressure monitoring performance. GM’s TPC Spec number is molded onto the tire’s sidewall near the tire size. If the tires have an all-season tread design, the TPC spec number will be followed by a MS, for mud and snow. See Tire Sidewall Labeling on page 6-61 for additional information. GM recommends replacing tires in sets of four (or six if your vehicle has dual rear wheels). This is because uniform tread depth on all tires will help keep your vehicle performing most like it did when the tires were new. Replacing less than a full set of tires can affect the braking and handling performance of your vehicle. See Tire Inspection and Rotation on page 6-75 for information on proper tire rotation.

{ WARNING:

Mixing tires could cause you to lose control while driving. If you mix tires of different sizes, brands, or types (radial and bias-belted tires) the vehicle may not handle properly, and you could have a crash. Using tires of different sizes, brands, or types may also cause damage to your vehicle. Be sure to use the correct size, brand, and type of tires on your vehicle’s wheels.

{ WARNING:

If you use bias-ply tires on the vehicle, the wheel rim flanges could develop cracks after many miles of driving. A tire and/or wheel could fail suddenly, causing a crash. Use only radial-ply tires with the wheels on the vehicle.

If you must replace your vehicle’s tires with those that do not have a TPC Spec number, make sure they are the same size, load range, speed rating, and construction type (radial and bias-belted tires) as your vehicle’s original tires.

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Vehicles that have a tire pressure monitoring system could give an inaccurate low-pressure warning if non-TPC Spec rated tires are installed on your vehicle. Non-TPC Spec rated tires may give a low-pressure warning that is higher or lower than the proper warning level you would get with TPC Spec rated tires. See Tire Pressure Monitor System on page 6-70. Your vehicle’s original equipment tires are listed on the Tire and Loading Information label. See Loading the Vehicle on page 5-19, for more information about the Tire and Loading Information label and its location on your vehicle.

Different Size Tires and Wheels If you add wheels or tires that are a different size than your original equipment wheels and tires, this could affect the way your vehicle performs, including its braking, ride and handling characteristics, stability, and resistance to rollover. Additionally, if your vehicle has electronic

systems such as anti-lock brakes, rollover airbags, traction control, and electronic stability control, the performance of these systems can be affected.

{ WARNING:

If you add different sized wheels, your vehicle may not provide an acceptable level of performance and safety if tires not recommended for those wheels are selected. You may increase the chance that you will crash and suffer serious injury. Only use GM specific wheel and tire systems developed for your vehicle, and have them properly installed by a GM certified technician.

See Buying New Tires on page 6-79 and Accessories and Modifications on page 6-3 for additional information.

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Uniform Tire Quality Grading Quality grades can be found where applicable on the tire sidewall between tread shoulder and maximum section width. For example: Treadwear 200 Traction AA Temperature A The following information relates to the system developed by the United States National Highway Traffic Safety Administration (NHTSA), which grades tires by treadwear, traction, and temperature performance. This applies only to vehicles sold in the United States. The grades are molded on the sidewalls of most passenger car tires. The Uniform Tire Quality Grading (UTQG) system does not apply to deep tread, winter-type snow tires, space-saver, or temporary use spare tires, tires with nominal rim diameters of 10 to 12 inches (25 to 30 cm), or to some limited-production tires. While the tires available on General Motors passenger cars and light trucks may vary with respect to these grades, they must also conform to federal safety requirements and additional General Motors Tire Performance Criteria (TPC) standards.

Treadwear The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150
would wear one and a half (1.5) times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices, and differences in road characteristics and climate. Traction – AA, A, B, C The traction grades, from highest to lowest, are AA, A, B, and C. Those grades represent the tire’s ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. A tire marked C may have poor traction performance.

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Temperature – A, B, C The temperature grades are A (the highest), B, and C, representing the tire’s resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the material of the tire to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure. The grade C corresponds to a level of performance which all passenger car tires must meet under the Federal Motor Vehicle Safety Standard No. 109. Grades B and A represent higher levels of performance on the laboratory test wheel than the minimum required by law. It should be noted that the temperature grade for this tire is established for a tire that is properly inflated and not overloaded. Excessive speed, underinflation, or excessive loading, either separately or in combination, can cause heat buildup and possible tire failure.

Wheel Alignment and Tire Balance The tires and wheels on your vehicle were aligned and balanced carefully at the factory to give you the longest tire life and best overall performance. Adjustments to wheel alignment and tire balancing will not be necessary on a regular basis. However, if you notice unusual tire wear or your vehicle pulling to one side or the other, the alignment might need to be checked. If you notice your vehicle vibrating when driving on a smooth road, the tires and wheels might need to be rebalanced. See your dealer/retailer for proper diagnosis.

Wheel Replacement Replace any wheel that is bent, cracked, or badly rusted or corroded. If wheel nuts keep coming loose, the wheel, wheel bolts and wheel nuts should be replaced. If the wheel leaks air, replace it (except some aluminum wheels, which can sometimes be repaired). See your dealer/retailer if any of these conditions exist.

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Your dealer/retailer will know the kind of wheel you need. Each new wheel should have the same load-carrying capacity, diameter, width, offset and be mounted the same way as the one it replaces. If you need to replace any of the wheels, wheel bolts, wheel nuts or Tire Pressure Monitor System (TPMS) sensors, replace them only with new GM original equipment parts. This way, you will be sure to have the right wheel, wheel bolts, wheel nuts, and TPMS sensors for the vehicle.

{ WARNING:

Using the wrong replacement wheels, wheel bolts, or wheel nuts on your vehicle can be dangerous. It could affect the braking and handling of your vehicle, make your tires lose air and make you lose control. You could have a collision in which you or others could be injured. Always use the correct wheel, wheel bolts, and wheel nuts for replacement.

Notice: The wrong wheel can also cause problems with bearing life, brake cooling, speedometer or odometer calibration, headlamp aim, bumper height, vehicle ground clearance, and tire or tire chain clearance to the body and chassis. Whenever a wheel, wheel bolt or wheel nut is replaced on a dual wheel setup, check the wheel nut torque after 100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km) of driving. For proper torque, see “Wheel Nut Torque” under Capacities and Specifications on page 6-116. See Changing a Flat Tire on page 6-86 for more information. Used Replacement Wheels

{ WARNING:

Putting a used wheel on the vehicle is dangerous. You cannot know how it has been used or how far it has been driven. It could fail suddenly and cause a crash. If you have to replace a wheel, use a new GM original equipment wheel.

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Tire Chains

{ WARNING:

If your vehicle has dual wheels or P245/70R17 or LT245/75R16 size tires, do not use tire chains. They can damage your vehicle because there is not enough clearance. Tire chains used on a vehicle without the proper amount of clearance can cause damage to the brakes, suspension, or other vehicle parts. The area damaged by the tire chains could cause you to lose control of your vehicle and you or others may be injured in a crash. Use another type of traction device only if its manufacturer recommends it for use on your vehicle and tire size combination and road conditions. Follow that manufacturer’s instructions.

WARNING:

(Continued)

WARNING:

(Continued)

To help avoid damage to your vehicle, drive slowly, readjust, or remove the device if it is contacting your vehicle, and do not spin the vehicle’s wheels. If you do find traction devices that will fit, install them on the rear tires.

If your vehicle does not have dual wheels

Notice: and has a tire size other than P245/70R17 or LT245/75R16, use tire chains only where legal and only when you must. Use chains that are the proper size for your tires. Install them on the tires of the rear axle. Do not use chains on the tires of the front