2007 Chevrolet Suburban Owners Manual

WASHER FLUID LOW ADD FLUID message is displayed, you will need to add washer fluid to the windshield washer fluid reservoir.

Open the cap with the washer symbol on it. Add washer fluid until the tank is full. See Engine Compartment Overview on page 458
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.

(cid:129) Fill your washer fluid tank only

three-quarters full when it is very cold. This allows for 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 your washer system and paint.

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Your brake master cylinder reservoir is filled with DOT-3 brake fluid. See Engine Compartment Overview on page 458 for the location of the reservoir.

There are only two reasons why the brake fluid level in the reservoir might go down. The first is that the brake fluid goes down to an acceptable level during normal brake lining wear. When new linings are put in, the fluid level goes back up. The other reason is that fluid is leaking out of the brake system. If it is, you should have your brake system fixed, since a leak means that sooner or later your brakes will not work well, or will not work at all. So, it is not a good idea to top off your brake fluid. Adding brake fluid will not correct a leak. If you add fluid when your linings are worn, then you will have too much fluid when you get new brake linings. You should add or remove brake fluid, as necessary, only when work is done on the brake hydraulic system.

Brakes Brake Fluid

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{CAUTION:

If you have too much brake fluid, it can spill on the engine. The fluid will burn if the engine is hot enough. You or others could be burned, and your vehicle could be damaged. Add brake fluid only when work is done on the brake hydraulic system. See “Checking Brake Fluid” in this section.

When the brake fluid falls to a low level, the brake warning light will come on. See Brake System Warning Light on page 249. Refer to the Maintenance Schedule to determine when to check your brake fluid. See Scheduled Maintenance on page 579.

Checking Brake Fluid You can check the brake fluid without taking off the cap.

Look at the brake fluid reservoir. The fluid level should be above MIN. If it is not, have your brake 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.

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What to Add When you do need brake fluid, use only DOT-3
brake fluid. Use new brake fluid from a sealed container only. See Recommended Fluids and Lubricants on page 590. Always clean the brake fluid reservoir cap and the area around the cap before removing it. This will help keep dirt from entering the reservoir.

{CAUTION:

With the wrong kind of fluid in the brake system, the brakes may 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 system parts. For example, just a few drops of mineral-based oil, such as engine oil, in the brake system can damage brake system parts so badly that they will have to be replaced. Do not let someone put in the wrong kind of fluid. If you spill brake fluid on your vehicle’s painted surfaces, the paint finish can be damaged. Be careful not to spill brake fluid on your vehicle. If you do, wash it off immediately. See Washing Your Vehicle on page 557.

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(cid:129) Brake Wear Your vehicle has four-wheel 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 may come and go or be heard all the time your vehicle is moving, except when you are pushing on the brake pedal firmly.

{CAUTION:

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

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

Some driving conditions or climates may cause a brake squeal when the brakes are first applied or lightly applied. This does not mean something is wrong with your 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 GM torque specifications. Brake linings should always be replaced as complete axle sets. Brake Pedal Travel See your dealer 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 of brake trouble. Brake Adjustment Every time you make a brake stop, your disc brakes adjust for wear.

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Warning: 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. Vehicle Storage If you are not going to drive your vehicle for 25 days or more, remove the black, negative (−) cable from the battery. This will help keep the battery from running down.

{CAUTION:

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 491 for tips on working around a battery without getting hurt.

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. Your vehicle was designed and tested with top-quality GM brake parts. When you replace parts of your braking system — for example, when your brake linings wear down and you need new ones put in — be sure you get new approved GM replacement parts. If you do not, your brakes may no longer work properly. For example, if someone puts in brake linings that are wrong for your vehicle, the balance between your front and rear brakes can change — for the worse. The braking performance you have come to expect can change in many other ways if someone puts in the wrong replacement brake parts.

Battery Your vehicle has a maintenance free battery. When it is time for a new battery, get one that has the replacement number shown on the original battery’s label. We recommend an ACDelco® replacement battery. See Engine Compartment Overview on page 458 for battery location.

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Jump Starting If your vehicle’s battery (or batteries) 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.

{CAUTION:

Batteries can hurt you. They can be dangerous because:

(cid:129) They contain acid that can burn you. (cid:129) They contain gas that can explode or

(cid:129) They contain enough electricity to

ignite.

burn you.

If you do not follow these steps exactly, some or all of these things can hurt you.

Ignoring these steps could result in

Notice: costly damage to your vehicle that would not be covered by your warranty.

Trying to start your vehicle by pushing or pulling it will not work, and it could damage your 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

Notice: 12-volt 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 the automatic transmission in PARK (P) or a manual transmission in NEUTRAL before setting the parking brake. If you have a four-wheel-drive vehicle, be sure the transfer case is in a drive gear, not in NEUTRAL.

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

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

4. Open the hood on the other vehicle and locate

the positive (+) and negative (−) terminal locations on that 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, if equipped, is located under a red plastic cover at the positive battery post. To uncover the remote positive (+) terminal, open the red plastic cover.

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The remote negative (-) terminal is a stud located on the right front of the engine, where the negative battery cable attaches. See Engine Compartment Overview on page 458
for more information on the location of the remote positive (+) and remote negative (-) terminals.

{CAUTION:

An electric fan can start up even when the engine is not running and can injure you. Keep hands, clothing and tools away from any underhood electric fan.

{CAUTION:

Using a match 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

CAUTION:

(Continued)

CAUTION:

(Continued)

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.

{CAUTION:

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.

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

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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.

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 the remote negative (−) terminal on the vehicle with the dead battery.

9. Connect the other end of the negative (−) cable to the remote negative (−) terminal, on the vehicle with the dead battery.

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.

Notice: If the jumper cables are connected or removed in the wrong order, electrical shorting may occur and damage the vehicle. The repairs would not be covered by your 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.

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

the vehicle that had the bad 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,

if equipped, to its original position.

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

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Rear Axle When to Check Lubricant It is not necessary to regularly check rear axle fluid unless you suspect there is a leak or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired. All axle assemblies are filled by volume of fluid during production. They are not filled to reach a certain level. When checking the fluid level on any axle, variations in the readings can be caused by factory fill differences between the minimum and the maximum fluid volume. Also, if a vehicle has just been driven before checking the fluid level, it may appear lower than normal because fluid has traveled out along the axle tubes and has not drained back to the sump area. Therefore, a reading taken five minutes after the vehicle has been driven will appear to have a lower fluid level than a vehicle that has been stationary for an hour or two. Remember that the rear axle assembly must be supported to get a true reading.

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How to Check Lubricant

To get an accurate reading, the vehicle should be on a level surface. (cid:129) For 4.8L and 5.3L engines, the proper level is

from 0.04 inch to 0.75 inch (1.0 mm to 19.0 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

(cid:129) For 6.0L engines, the proper level is from

0.6 inch to 1.6 inches (15 mm to 40 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

(cid:129) The proper fill level for the 2500 Series is from 0 to 1/2 inch (0 to 13 mm) below the bottom of the filler plug hole, located at the front of the axle. Add only enough fluid to reach the proper level.

Four-Wheel Drive Lubricant checks in this section also apply to these vehicles. There are two additional systems that need lubrication. Transfer Case When to Check Lubricant It is not necessary to regularly check transfer case fluid unless you suspect there is a leak, or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired.

How to Check Lubricant

Automatic Transfer Case

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 will 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. When to Change Lubricant Refer to the Maintenance Schedule to determine how often to change the lubricant. See Scheduled Maintenance on page 579.

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What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 590. Front Axle When to Check and Change Lubricant It is not necessary to regularly check front axle fluid unless you suspect there is a leak or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired. How to Check Lubricant To get an accurate reading, the vehicle should be on a level surface.

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A: Fill Plug B: Drain Plug If the level is below the bottom of the filler plug hole, located on the front axle, you may need to add some lubricant: (cid:129) When the differential is cold, add enough

lubricant to raise the level from 0 (0 mm) to 1/8 inch (3.2 mm) below the filler plug hole.

(cid:129) 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 590. Headlamp Aiming The vehicle has a visual optical headlamp aiming system. The aim of the headlamps have been preset at the factory and should need no further adjustment. However, if the vehicle is damaged in an accident, the aim of the headlamps may be affected and adjustment may be necessary. If oncoming vehicles flash their high beams at you, this may mean the vertical aim of your headlamps needs to be adjusted. It is recommended that the vehicle is taken to your dealer/retailer for service if the headlamps need to be adjusted. It is possible however, to re-aim the headlamps as described in the following procedure.

The vehicle should be properly prepared as follows: (cid:129) The vehicle should be placed so the headlamps

are 25 ft. (7.6 m) from a light colored wall.

(cid:129) The vehicle must have all four tires on a level surface which is level all the way to the wall.

(cid:129) The vehicle should be placed so it is

perpendicular to the wall.

(cid:129) The vehicle should not have any snow, ice, or

mud on it.

(cid:129) The vehicle should be fully assembled and all other work stopped while headlamp aiming is being performed.

(cid:129) The vehicle should be normally loaded with a

full tank of fuel and one person or 160 lbs (75 kg) sitting on the driver’s seat. (cid:129) Tires should be properly inflated. (cid:129) The spare tire is in its proper location in the

vehicle.

Headlamp aiming is done with the vehicle’s low-beam headlamps. The high-beam headlamps will be correctly aimed if the low-beam headlamps are aimed properly.

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To adjust the vertical aim, do the following: 1. Open the hood. See Hood Release on

page 457 for more information.

4. At the wall or other flat surface, measure from

the ground upward (A) to the recorded distance from Step 3 and mark it.

5. Draw or tape a horizontal line (B) on the wall or flat surface the width of the vehicle at the height of the mark in Step 4.

Notice: Do not cover a headlamp to improve beam cut-off when aiming. Covering a headlamp may cause excessive heat build-up which may cause damage to the headlamp. 6. Turn on the low-beam headlamps and place a piece of cardboard or equivalent in front of the headlamp not being adjusted. This allows only the beam of light from the headlamp being adjusted to be seen on the flat surface.

2. Locate the aim dot on the lens of the

low-beam headlamp.

3. Measure the distance from the ground to the aim dot on the low-beam headlamp. Record the distance.

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9. Make sure that the light from the headlamp is positioned at the bottom edge of the horizontal tape line. The lamp on the left (A) shows the correct headlamp aim. The lamp on the right (B) shows the incorrect headlamp aim.

10. Repeat Steps 7 through 9 for the opposite

headlamp.

7. Locate the vertical headlamp aiming screws,

which are under the hood near each headlamp assembly. The adjustment screw can be turned with a E8 Torx® socket.

8. Turn the vertical aiming screw until the

headlamp beam is aimed to the horizontal tape line. Turn it clockwise or counterclockwise to raise or lower the angle of the beam.

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Taillamps, Turn Signal, Stoplamps and Back-up Lamps

A. Taillamp/Stoplamp B. Back-up Lamp C. Turn Signal

Lamp/Taillamp

Bulb Replacement For the proper type of replacement bulbs, see Replacement Bulbs on page 504. For any bulb changing procedure not listed in this section, contact your dealer.

Halogen Bulbs

{CAUTION:

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.

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To replace one of these bulbs, do the following:

1. Open the liftgate. See Power Liftgate on

page 127 for more information.

2. Remove the two screws from the taillamp assembly.

4. Press the release tab, if bulb socket has one, and turn the bulb socket counterclockwise to remove it from the taillamp assembly.

5. Pull the old bulb straight out from the bulb

socket.

6. Press a new bulb into the bulb socket and

insert it into the taillamp assembly. Turn the bulb socket clockwise into the taillamp assembly until it clicks.

7. Reinstall the taillamp assembly. When

reinstalling, make sure to line up the pins on the taillamp assembly with the vehicle. If you do not do this, you will not be able correctly install the taillamp assembly.

3. Pull the taillamp assembly rearward until you

disengage the inner pins on the taillamp assembly from the vehicle.

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3. Turn the bulb socket counterclockwise and

pull the bulb straight out of the socket.

4. Install the new bulb. 5. Reverse Steps 1 through 3 to reinstall the

license plate lamp.

Replacement Bulbs

Exterior Lamp

Back-up Lamp License Plate Lamp Rear Turn Signal Lamp, Taillamp, and Stoplamp

Bulb Number 3047
168

3047

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

License Plate Lamp

1. Remove the two screws holding each of the

license plate lamps to the molding that is part of the liftgate.

2. Twist and pull the license plate lamp forward

through the molding opening.

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Windshield Wiper Blade Replacement Windshield wiper blades should be inspected for wear or cracking. See Scheduled Maintenance on page 579. Replacement blades come in different types and are removed in different ways. To replace the wiper blade assembly, do the following: 1. Pull the windshield wiper arm connector away

from the windshield.

3. Install the new blade onto the arm connector

and make sure the grooved areas are fully set in the locked position.

For the proper type and size, see Normal Maintenance Replacement Parts on page 592.

2. Squeeze the grooved areas on each side of

the blade, and rotate the blade assembly away from the arm connector.

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Backglass Wiper Blade Replacement 1. Lift the wiper blade assembly up and out

of the park rest position.

2. Pull the wiper blade assembly away from the backglass. The backglass wiper blade will not lock in a vertical position, so care should be used when pulling it away from the vehicle.

3. Rotate the wiper blade assembly, and pull it

off of the wiper arm. Hold the wiper arm in position and push the blade away from the wiper arm.

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4. Replace the wiper blade. 5. Return the wiper blade assembly to the park

rest position.

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 GM Warranty booklet for details. For additional information refer to the tire manufacturer’s booklet included with your vehicle.

{CAUTION:

Poorly maintained and improperly used tires are dangerous.

(cid:129) Overloading your vehicle’s tires can cause overheating as a result of too much friction. You could have an air-out and a serious accident. See Loading Your Vehicle on page 407. (cid:129) 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.

CAUTION:

(Continued)

CAUTION:

(Continued)

Tire pressure should be checked when your vehicle’s tires are cold. See Inflation - Tire Pressure on page 515.

(cid:129) 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.

(cid:129) 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.

20-Inch Tires If your vehicle has the optional 20-inch P275/55R20 size tires, they are classified as touring tires and are designed for on road use. The low-profile, wide tread design is not recommended for off-road driving. See Off-Road Driving on page 372, for additional information.

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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.

(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.

Passenger (P-Metric) Tire

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(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 527.

(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 515 and Loading Your Vehicle on page 407.

Light Truck (LT-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.

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(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) 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 515 and Loading Your Vehicle on page 407.

(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 515 and Loading Your Vehicle on page 407.

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

Passenger (P-Metric) Tire

Light Truck (LT-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.

(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) Service Description: The service description indicates the load range and speed rating of a tire. The load index can range from 1 to 279. Speed ratings range from A to Z.

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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 515.

Curb Weight: This means 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 Your Vehicle on page 407.

GAWR FRT: Gross Axle Weight Rating for the front axle. See Loading Your Vehicle on page 407.

GAWR RR: Gross Axle Weight Rating for the rear axle. See Loading Your Vehicle on page 407.

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 may 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 Your Vehicle on page 407.

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 515 and Loading Your Vehicle on page 407.

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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 523.

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 527.

Vehicle Capacity Weight: The number of designated seating positions multiplied by 150 lbs (68 kg) plus the rated cargo load. See Loading Your Vehicle on page 407.

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 Your Vehicle on page 407.

514

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 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 Tire and Loading Information label is attached to the vehicle’s center pillar (B-pillar), below the driver’s door lock post (striker). This label lists your vehicle’s original equipment tires and their recommended cold tire inflation pressures. 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 Your Vehicle on page 407. When to Check Check your tires once a month or more. Do not forget to check the spare tire. For additional information regarding the spare tire, see Spare Tire on page 552.

515

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’re 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 inflation 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.

Tire Pressure Monitor System The Tire Pressure Monitor System (TPMS) uses radio and sensor technology to check tire pressure levels. If your vehicle has this feature, sensors are mounted on each tire and wheel assembly, except the spare tire. The TPMS sensors monitor the air pressure in your vehicle’s tires and transmit tire pressure readings to a receiver located in the vehicle. The TPMS is designed to alert the driver, if a low tire pressure condition exists. If your vehicle has the Driver Information Center (DIC), the driver may also check tire pressure levels using the DIC. When a low tire pressure condition is detected, the TPMS will illuminate the low tire pressure warning symbol located on the instrument panel cluster. If your vehicle has the DIC feature, a message to check the pressure in a specific tire will also appear on the DIC display. The low tire pressure warning symbol on the instrument panel cluster and the CHECK TIRE PRESSURE warning message on the DIC display will appear at each ignition cycle until the tires are inflated to the correct inflation pressure.

516

For additional information and details about the DIC operation and displays see DIC Operation and Displays (With DIC Buttons) on page 261 or DIC Operation and Displays (Without DIC Buttons) on page 267 and DIC Warnings and Messages on page 270. You may notice, during cooler weather conditions, that the tire pressure monitor light, located on the instrument panel cluster, and the CHECK TIRE PRESSURE message will appear when the vehicle is first started and then turn off as you start to drive the vehicle. This could be an early indicator that the tire pressures are getting low and need to be inflated to the proper pressure. 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.

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.

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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.

The CHECK TIRE PRESSURE warning message and low tire pressure light (telltale) will come on each time the vehicle is started until the tires are inflated to the correct inflation pressure. The Tire and Loading Information label (tire information placard) shows the size of your vehicle’s original tires and the correct inflation pressure for your vehicle’s tires when they are cold. See Inflation - Tire Pressure on page 515. For the location of the tire and loading information label, see Loading Your Vehicle on page 407. Your vehicle’s TPMS can alert you about a low tire pressure condition but it does not replace normal tire maintenance. See Tire Inspection and Rotation on page 521 and Tires on page 507. Notice: Do not use a tire sealant if your vehicle has Tire Pressure Monitors. The liquid sealant can damage the tire pressure monitor sensors.

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Resetting the TPMS Identification Codes 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’s side front tire, passengers side front tire, passengers side rear tire, and driver’s side rear tire using a TPMS diagnostic tool. See your GM dealer for service. The TPMS sensors may 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. You will 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 will need to start over.

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

engine off.

3. Using the DIC, press the vehicle information button until the RELEARN TIRE POSITIONS message displays. If your vehicle does not have the DIC buttons, press the trip odometer reset stem located on the instrument panel cluster until the RELEARN TIRE POSITIONS message displays.

4. If your vehicle has the DIC buttons, press the set/reset button. The horn will sound twice to indicate the TPMS receiver is ready, and the TIRE LEARNING ACTIVE message will display. If your vehicle does not have the DIC buttons, press and hold the trip odometer reset stem until the horn chirps twice and the TIRE LEARNING ACTIVE message is displayed.

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5. Start with the driver’s side front tire. 6. 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 make take up to 30 seconds to sound, confirms that the sensor identification code has been matched to this tire and wheel position. 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.

7. Proceed to the passenger’s side front tire, and

repeat the procedure in Step 6.

8. Proceed to the passenger’s side rear tire, and

repeat the procedure in Step 6.

9. Proceed to the driver’s side rear tire, and

repeat the procedure in Step 6.

10. After hearing the confirming horn chirp for the driver’s side rear tire, the horn chirp will sound two more times to signal the tire learning mode is no longer active. Turn the ignition switch to LOCK.

11. Set all four tires to the recommended air

pressure level as indicated on the Tire and Loading Information label.

12. Put the valve caps back on the valve stems The spare tire does not have a TPMS sensor. If you replace one of the road tires with the spare, the SERVICE TIRE MONITOR message will be displayed on the DIC screen. This message should go off once you re-install the road tire containing the TPMS sensor.

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Federal Communications Commission (FCC) and Industry and Science Canada The Tire Pressure Monitor System (TPMS) operates on a radio frequency and complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: 1. This device may not cause harmful

interference.

2. This device must accept any interference received, including interference that may cause undesired operation.

The Tire Pressure Monitor System (TPMS) operates on a radio frequency and complies with RSS-210 of Industry and Science Canada. Operation is subject to the following two conditions: 1. This device may not cause interference. 2. This device must accept any interference received, including interference that may cause undesired operation of the device.

Changes or modifications to this system by other than an authorized service facility could void authorization to use this equipment.

Tire Inspection and Rotation Tires should be rotated every 5,000 to 8,000 miles (8 000 to 13 000 km). Any time you notice unusual wear, rotate your 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 523
and Wheel Replacement on page 528 for more information. Make sure the spare tire is stored securely. Push, pull, and then try to rotate or turn the tire. If it moves, use the ratchet/wheel wrench to tighten the cable. See Changing a Flat Tire on page 532. The purpose of regular rotation is to achieve more uniform wear for all tires on the vehicle. The first rotation is the most important. See Scheduled Maintenance on page 579.

521

Make certain that all wheel nuts are properly tightened. See “Wheel Nut Torque” under Capacities and Specifications on page 572.

{CAUTION:

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 532.

When rotating your vehicle’s tires, always use the correct rotation pattern shown here. Do not include the spare tire in the tire rotation. After the tires have been rotated, adjust the front and rear inflation pressures as shown on the tire and loading information label. See Loading Your Vehicle on page 407 and Inflation - Tire Pressure on page 515, for more information. Vehicles that have the Tire Pressure Monitor System (TPMS) will need to have the TPMS sensors reset after a tire rotation. See “TPMS Sensor Identification Codes” under Tire Pressure Monitor System on page 516.

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When It Is Time for New Tires

One way to tell when it is time for new tires is to check the treadwear indicators, which will appear when your tires have only 1/16 inch (1.6 mm) or less of tread remaining. Some commercial truck tires may not have treadwear indicators.

You need a new tire if any of the following statements are true: (cid:129) You can see the indicators at three or more

places around the tire.

(cid:129) You can see cord or fabric showing through

the tire’s rubber.

(cid:129) The tread or sidewall is cracked, cut or

snagged deep enough to show cord or fabric.

(cid:129) The tire has a bump, bulge, or split. (cid:129) The tire has a puncture, cut, or other damage

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

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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 by the tire manufacturer. If the tires have an all-season tread design, the TPC spec number will be followed by an MS for mud and snow. See Tire Sidewall Labeling on page 508 for additional information.

524

{CAUTION:

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 same size, brand, and type tires on all wheels. Your vehicle may have a different size spare than the road tires (those originally installed on your vehicle). When new, your vehicle included a spare tire and wheel assembly with a similar overall diameter as your vehicle’s road tires and wheels, so it is all right to drive on it. Because this spare was developed for use on your vehicle, it will not affect vehicle handling.

{CAUTION:

If you use bias-ply tires on your 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 your 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.

Vehicles that have a tire pressure monitoring system may 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 516. Your vehicle’s original equipment tires are listed on the Tire and Loading Information Label. This label is attached to the vehicle’s center pillar (B-pillar). See Loading Your Vehicle on page 407, for more information about the Tire and Loading Information Label and its location on your vehicle.

525

Different Size Tires and Wheels If you add wheels or tires that are a different size than your original equipment wheels and tires, this may 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, traction control, and electronic stability control, the performance of these systems can be affected.

{CAUTION:

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 524 and Accessories and Modifications on page 444 for additional information.

526

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. Warning: The traction grade assigned to this tire is based on straight-ahead braking traction tests, and does not include acceleration, cornering, hydroplaning, or peak traction characteristics.

527

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. Warning: 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 may need to be checked. If you notice your vehicle vibrating when driving on a smooth road, your tires and wheels may 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. Your dealer/retailer will know the kind of wheel you need.

528

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 your wheels, wheel bolts, or wheel nuts, replace them only with new GM original equipment parts. This way, you will be sure to have the right wheel, wheel bolts, and wheel nuts for your vehicle.

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. See Changing a Flat Tire on page 532 for more information. Used Replacement Wheels

{CAUTION:

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.

{CAUTION:

Putting a used wheel on your 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.

529

Tire Chains

{CAUTION:

If your vehicle has P265/65R18 or P275/55R20 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. CAUTION:

(Continued)

530

CAUTION:

(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 your vehicle’s wheels. If you do find traction devices that will fit, install them on the rear tires.

If your vehicle has P265/70R17 size

Notice: tires, use tire chains only where legal and only when you must. Use chains that are the proper size for your vehicle’s tires. Install them on the rear tires only. Do not use chains on the front tires. Tighten them as tightly as possible with the ends securely fastened. Drive slowly and follow the chain manufacturer’s instructions. If you can hear the chains contacting your vehicle, stop and retighten them. If the contact continues, slow down until it stops. Driving too fast or spinning the wheels with chains on will damage your vehicle.

If a Tire Goes Flat It is unusual for a tire to blowout while you are driving, especially if you maintain your vehicle’s tires properly. If air goes out of a tire, it is much more likely to leak out slowly. But if you should ever have a blowout, here are a few tips about what to expect and what to do: If a front tire fails, the flat tire will create a drag that pulls the vehicle toward that side. Take your foot off the accelerator pedal and grip the steering wheel firmly. Steer to maintain lane position, and then gently brake to a stop well out of the traffic lane. A rear blowout, particularly on a curve, acts much like a skid and may require the same correction you would use in a skid. In any rear blowout remove your foot from the accelerator pedal. Get the vehicle under control by steering the way you want the vehicle to go. It may be very bumpy and noisy, but you can still steer. Gently brake to a stop, well off the road if possible.

{CAUTION:

Lifting a vehicle and getting under it to do maintenance or repairs is dangerous without the appropriate safety equipment and training. The jack provided with your vehicle is designed only for changing a flat tire. If it is used for anything else, you or others could be badly injured or killed if the vehicle slips off the jack. Use the jack provided with your vehicle only for changing a flat tire.

If a tire goes flat, the next part shows how to use the jacking equipment to change a flat tire safely.

531

CAUTION:

(Continued)

3. If you have a four-wheel-drive vehicle, be sure the transfer case is in a drive gear— not in NEUTRAL.

4. Turn off the engine and do not restart

while the vehicle is raised.

5. Do not allow passengers to remain in

the vehicle.

6. Put the wheel blocks at the front and rear of the tire farthest away from the one being changed. That would be the tire on the other side, at the opposite end of the vehicle.

Changing a Flat Tire If a tire goes flat, avoid further tire and wheel damage by driving slowly to a level place. Turn on your hazard warning flashers. See Hazard Warning Flashers on page 204 for more information.

{CAUTION:

Changing a tire can be dangerous. The vehicle can slip off the jack and roll over or fall on you or other people. You and they could be badly injured or even killed. Find a level place to change your tire. To help prevent the vehicle from moving:

1. Set the parking brake firmly. 2. Put the shift lever in PARK (P).

CAUTION:

(Continued)

532

When your vehicle has a flat tire, use the following example as a guide to assist you in the placement of wheel blocks.

Removing the Spare Tire and Tools The equipment you will need to change a flat tire is stored under the storage tray, which is located on the driver’s side trim panel (over the rear wheelhouse).

The following information will tell you how to use the jack and change a tire.

Regular Wheelbase shown, Extended Wheelbase

similar.

1. Remove the tray to access the tools by pulling

up on the finger depression under the jack symbol.

533

2. Remove the wing nut (B) used to retain the

tool bag by turning it counterclockwise.

3. Turn the knob (A) on the jack

counterclockwise to release the jack and wheel blocks from the bracket.

4. Remove the wheel blocks and the wheel block retainer by turning the wing nut (C) counterclockwise.

The tools you will be using include the following:

A. Jack B. Wheel Blocks C. Jack Handle

D. Jack Handle

Extensions

E. Wheel Wrench

534

To access the spare tire, refer to the following graphics and instructions:

1. Open the hoist shaft access door (C) on the

bumper to access the spare tire lock (K).

2. Insert the ignition key, turn it clockwise and

then pull it to remove the spare tire lock.

A. Hoist Assembly B. Hoist Shaft C. Hoist Shaft

Access Cover/Hole D. Jack Handle

Extensions

E. Wheel Wrench F. Hoist Cable

G. Tire Retainer H. Spare Tire

(Valve Stem Pointed Down)

I. Hoist Shaft

Access Hole J. Hoist End of

Extension Tool

K. Spare Tire Lock

3. Assemble the two jack handle extensions (D)

and wheel wrench (E) as shown.

535

4. Insert the open end of the extension (J) through the hole in the rear bumper (I) (hoist shaft access hole).

Be sure the hoist end (J) of the extension (D) connects to the hoist shaft (B). The ribbed square end of the extension is used to lower the spare tire.

5. Turn the wheel wrench (E) counterclockwise

to lower the spare tire (H) to the ground. Continue to turn the wheel wrench until the spare tire can be pulled out from under the vehicle. If the spare tire does not lower to the ground, the secondary latch is engaged causing the tire not to lower. See Secondary Latch System on page 543 for more information.

536

6. Use the wheel

wrench hook that allows you to pull the hoist cable towards you, to assist in reaching the spare tire.

7. Tilt the tire

retainer (G) at the end of the cable when the tire has been lowered, so it can be pulled up through the wheel opening.

8. Put the spare tire near the flat tire.

Removing the Flat Tire and Installing the Spare Tire Use the following pictures and instructions to remove the flat tire and raise the vehicle.

If the wheel has bolt-on wheel covers, loosen the plastic nut caps by turning the wheel wrench counterclockwise. If needed, finish loosening them by hand. The nut caps will not come off. Using the flat end of the wheel wrench, pry along the edge of the cover until it comes off.

1. Remove the center cap, if your vehicle has one, by placing the chisel end of the wheel wrench in the slot on the wheel and gently pry the cap out.

2. Use the wheel wrench to loosen all the wheel nuts. Turn the wheel wrench counterclockwise to loosen the wheel nuts. Do not remove the wheel nuts yet.

537

{CAUTION:

Getting under a vehicle when it is jacked up is dangerous. If the vehicle slips off the jack you could be badly injured or killed. Never get under a vehicle when it is supported only by a jack.

{CAUTION:

Raising your vehicle with the jack improperly positioned can damage the vehicle and even make the vehicle fall. To help avoid personal injury and vehicle damage, be sure to fit the jack lift head into the proper location before raising the vehicle.

3. Position the jack under the vehicle as shown.

Jacking Locations (Overall View)

A. Front Position B. Rear Position

538

Turn the wheel wrench clockwise to raise the vehicle. Raise the vehicle far enough off the ground so there is enough room for the spare tire to clear the ground.

Front Position

Front Tire Flat: If the flat tire is on a front tire of the vehicle, you will need to use the jack handle and only one jack handle extension. Attach the wheel wrench to the jack handle extension. Attach the jack handle to the jack (A). Position the jack on the frame behind the flat tire where the frame sections overlap.

Rear Position – 1500 Models

539

Raise the vehicle far enough off the ground so there is enough room for the spare tire to clear the ground.

4. Remove all of the

wheel nuts.

5. Take off the flat tire.

Rear Position – All Other Models

Rear Tire Flat: If the flat tire is on a rear tire of the vehicle, you will need to use the jack handle (B) and both jack handle extensions (C). Attach the wheel wrench (D) to the jack handle extensions (C). Attach the jack handle (B) to the jack (A). Use the jacking pad provided on the rear axle. Turn the wheel wrench (D) clockwise to raise the vehicle.

540

{CAUTION:

Rust or dirt on the wheel, or on the parts to which it is fastened, can make the 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 the 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.

6. Remove any rust or dirt from the wheel bolts, mounting surfaces and spare wheel.

{CAUTION:

Never use oil or grease on studs or nuts. If you do, the nuts might come loose. Your wheel could fall off, causing a serious accident.

7. Put the wheel nuts back on with the rounded

end of the nuts toward the wheel after mounting the spare tire.

541

Improperly tightened wheel nuts can

Notice: lead to brake pulsation and rotor damage. To avoid expensive brake repairs, evenly tighten the wheel nuts in the proper sequence and to the proper torque specification. See Capacities and Specifications on page 572 for the wheel nut torque specification.

10. Tighten the nuts firmly in a crisscross

sequence as shown by turning the wheel wrench clockwise.

8. Tighten each wheel nut by hand. Then use

the wheel wrench to tighten the nuts until the wheel is held against the hub.

9. Turn the wheel wrench counterclockwise to

lower the vehicle. Lower the jack completely.

{CAUTION:

Incorrect wheel nuts or improperly tightened wheel nuts can cause the wheel to come loose and even come off. This could lead to an accident. Be sure to use the correct wheel nuts. If you have to replace them, be sure to get new GM original equipment wheel nuts. Stop somewhere as soon as you can and have the nuts tightened with a torque wrench to the proper torque specification. See Capacities and Specifications on page 572
for wheel nut torque specification.

542

When you reinstall the regular wheel and tire, you must also reinstall the either the center cap, or bolt-on hub cap, depending on what your vehicle has. For center caps, place the cap on the wheel and tap it into place until it seats flush with the wheel. The cap only goes on one way. Be sure to line up the tab on the center cap with the indentation on the wheel. For bolt-on hub caps, align the plastic nut caps with the wheel nuts and then tighten by hand. Then use the wheel wrench to tighten.

Secondary Latch System Your vehicle has an underbody-mounted tire hoist assembly which has a secondary latch system. It is designed to stop the spare tire from suddenly falling off your vehicle. For the secondary latch to work, the spare tire must be installed with the valve stem pointing down. See Storing a Flat or Spare Tire and Tools on page 547.

{CAUTION:

Before beginning this procedure read all the instructions. Failure to read and follow the instructions could damage the hoist assembly and you and others could get hurt. Read and follow the instructions listed next.

To release the spare tire from the secondary latch, do the following:

1. Check under the

vehicle to see if the cable end is visible. If the cable is not visible, proceed to Step 6.

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7. Place the bottom

edge of the jack (A) on the wheel blocks (B), separating them so that the jack is balanced securely.

2. If it is visible, first try to tighten the cable by turning the wheel wrench clockwise until you hear two clicks or feel it skip twice. You cannot overtighten the cable.

3. Loosen the cable by turning the wheel wrench

counterclockwise three or four turns.

4. Repeat this procedure at least two times. If the spare tire lowers to the ground, continue with Step 5 of Removing the Spare Tire and Tools on page 533.

5. If the spare tire does not lower, turn the wheel

wrench counterclockwise until approximately 6 inches (15 cm) of cable is exposed.

6. Stand the wheel blocks on their shortest ends,

with the backs facing each other.

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8. Attach the jack handle, extension, and wheel

wrench to the jack and place it (with the wheel blocks) under the vehicle toward the front of the rear bumper.

9. Position the center lift point of the jack under

the center of the spare tire.

10. Turn the wheel wrench clockwise to raise the

jack until it lifts the end fitting.

545

13. Disconnect the jack handle from the jack and carefully remove the jack with the other hand. 14. Use one hand to push against the spare while

firmly pulling the jack out from under the spare tire with the other hand. If the spare tire is hanging from the cable, insert the hoist end of the extension, and wheel wrench into the hoist shaft hole in the bumper and turn the wheel wrench counterclockwise to lower the spare tire the rest of the way.

11. Continue raising the jack until the spare tire

stops moving upward and is held firmly in place so that the secondary latch has released and the spare tire is balancing on the jack. 12. Lower the jack by turning the wheel wrench

counterclockwise. Keep lowering the jack until the spare tire slides off the jack or is hanging by the cable.

{CAUTION:

Someone standing too close during the procedure could be injured by the jack. If the spare tire does not slide off the jack completely, make sure no one is behind you or on either side of you as you pull the jack out from under the spare.

546

15. Tilt the tire retainer

at the end of the cable and pull it through the wheel opening. Pull the tire out from under the vehicle.

16. Turn the wheel wrench in the hoist shaft hole

in the bumper clockwise to raise the cable back up if the cable is hanging under the vehicle.

Have the hoist assembly inspected as soon as you can. You will not be able to store a spare or flat tire using the hoist assembly until it has been replaced. To continue changing the flat tire, see Removing the Flat Tire and Installing the Spare Tire on page 537.

Storing a Flat or Spare Tire and Tools