2003 GMC Sierra Owners Manual

Hydroplaning Hydroplaning is dangerous. So much water can build up under your tires that they can actually ride on the water. This can happen if the road is wet enough and you’re going fast enough. When your vehicle is hydroplaning, it has little or no contact with the road. Hydroplaning doesn’t happen often. But it can if your tires do not have much tread or if the pressure in one or more is low. It can happen if a lot of water is standing on the road. If you can see reflections from trees, telephone poles or other vehicles, and raindrops “dimple” the water’s surface, there could be hydroplaning. Hydroplaning usually happens at higher speeds. There just isn’t a hard and fast rule about hydroplaning. The best advice is to slow down when it is raining. Driving Through Deep Standing Water

Notice: If you drive too quickly through deep puddles or standing water, water can come in through your engine’s air intake and badly damage your engine. Never drive through water that is slightly lower than the underbody of your vehicle. If you can’t avoid deep puddles or standing water, drive through them very slowly.

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Some Other Rainy Weather Tips

City Driving

Turn on your low-beam headlamps - not just your parking lamps - to help make you more visible to others. Besides slowing down, allow some extra following distance. And be especially careful when you pass another vehicle. Allow yourself more clear room ahead, and be prepared to have your view restricted by road spray. Have good tires with proper tread depth. See Tires on page 5-72.

One of the biggest problems with city streets is the amount of traffic on them. You’ll want to watch out for what the other drivers are doing and pay attention to traffic signals.

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Here are ways to increase your safety in city driving:

Freeway Driving

Know the best way to get to where you are going. Get a city map and plan your trip into an unknown part of the city just as you would for a cross-country trip. Try to use the freeways that rim and crisscross most large cities. You’ll save time and energy. See the next part, “Freeway Driving.” Treat a green light as a warning signal. A traffic light is there because the corner is busy enough to need it. When a light turns green, and just before you start to move, check both ways for vehicles that have not cleared the intersection or may be running the red light.

Mile for mile, freeways (also called thruways, parkways, expressways, turnpikes or superhighways) are the safest of all roads. But they have their own special rules. The most important advice on freeway driving is: Keep up with traffic and keep to the right. Drive at the same speed most of the other drivers are driving. Too-fast or too-slow driving breaks a smooth traffic flow. Treat the left lane on a freeway as a passing lane.

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At the entrance, there is usually a ramp that leads to the freeway. If you have a clear view of the freeway as you drive along the entrance ramp, you should begin to check traffic. Try to determine where you expect to blend with the flow. Try to merge into the gap at close to the prevailing speed. Switch on your turn signal, check your mirrors and glance over your shoulder as often as necessary. Try to blend smoothly with the traffic flow. Once you are on the freeway, adjust your speed to the posted limit or to the prevailing rate if it’s slower. Stay in the right lane unless you want to pass. Before changing lanes, check your mirrors. Then use your turn signal. Just before you leave the lane, glance quickly over your shoulder to make sure there isn’t another vehicle in your “blind” spot. Once you are moving on the freeway, make certain you allow a reasonable following distance. Expect to move slightly slower at night. When you want to leave the freeway, move to the proper lane well in advance. If you miss your exit, do not, under any circumstances, stop and back up. Drive on to the next exit.

The exit ramp can be curved, sometimes quite sharply. The exit speed is usually posted. Reduce your speed according to your speedometer, not to your sense of motion. After driving for any distance at higher speeds, you may tend to think you are going slower than you actually are. Before Leaving on a Long Trip Make sure you’re ready. Try to be well rested. If you must start when you’re not fresh - such as after a day’s work - don’t plan to make too many miles that first part of the journey. Wear comfortable clothing and shoes you can easily drive in. Is your vehicle ready for a long trip? If you keep it serviced and maintained, it’s ready to go. If it needs service, have it done before starting out. Of course, you’ll find experienced and able service experts in dealerships all across North America. They’ll be ready and willing to help if you need it.

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Here are some things you can check before a trip:

Windshield Washer Fluid: Is the resewior full? Are all windows clean inside and outside? Wiper Blades: Are they in good shape? Fuel, Engine Oil, Other Fluids: Have you checked all levels? lamps: Are they all working? Are the lenses clean? Tires: They are vitally important to a safe, trouble-free trip. Is the tread good enough for long-distance driving? Are the tires all inflated to the recommended pressure? Weather Forecasts: What’s the weather outlook along your route? Should you delay your trip a short time to avoid a major storm system? Maps: Do you have up-to-date maps?

Highway Hypnosis Is there actually such a condition as “highway hypnosis”? Or is it just plain falling asleep at the wheel? Call it highway hypnosis, lack of awareness, or whatever. There is something about an easy stretch of road with the same scenery, along with the hum of the tires on the road, the drone of the engine, and the rush of the wind against the vehicle that can make you sleepy. Don’t let it happen to you! If it does, your vehicle can leave the road in less than a second, and you could crash and be injured. What can you do about highway hypnosis? First, be aware that it can happen. Then here are some tips:

Make sure your vehicle is well ventilated, with a comfortably cool interior. Keep your eyes moving. Scan the road ahead and to the sides. Check your mirrors and your instruments frequently. If you get sleepy, pull off the road into a rest, service or parking area and take a nap, get some exercise, or both. For safety, treat drowsiness on the highway as an emergency.

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Hill and Mountain Roads

Keep your vehicle in good shape. Check all fluid levels and also the brakes, tires, cooling system and transmission. These parts can work hard on mountain roads. Know how to go down hills. The most important thing to know is this: let your engine do some of the slowing down. Shift to a lower gear when you go down a steep or long hill.

If you don’ hift dow . your brakes could get so hot that they wouldn’t work well. You would then have poor braking or even none going down a hill. You could crash. Shift down to let your engine assist your brakes on a steep downhill slope.

Driving on steep hills or mountains is different from driving in flat or rolling terrain. If you drive regularly in steep country, or if you’re planning to visit there, here are some tips that can make your trips safer and more enjoyable. See Off-Road Driving with Your Four-Wheel-Drive Vehicle on page 4-27 for information about driving off-road.

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Coasting downhill in NEUTRA N) or with the ignition off is dangerous. Your brakes will have to do all the work of slowing down. They couldget so hot that they wouldn’t work well. You would then have poor braking or even none going down a hill. You could crash. Always have your engine running and your vehicle in gear when you go downhill.

0 Know how to go uphill. You may want to shift down

to a lower gear. The lower gears help cool your engine and transmission, and you can climb the hill better. Stay in your own lane when driving on two-lane roads in hills or mountains. Don’t swing wide or cut across the center of the road. Drive at speeds that let you stay in your own lane. As you go over the top of a hill, be alert. There could be something in your lane, like a stalled car or an accident. You may see highway signs on mountains that warn of special problems. Examples are long grades, passing or no-passing zones, a falling rocks area or winding roads. Be alert to these and take appropriate action.

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Winter Driving

Include an ice scraper, a small brush or broom, a supply of windshield washer fluid, a rag, some winter outer clothing, a small shovel, a flashlight, a red cloth and reflective warning triangles. And, if you will be driving under severe conditions, include a small bag of sand, a piece of old carpet or a couple of burlap bags to help provide traction. Be sure you properly secure these items in your vehicle. Driving on Snow or Ice Most of the time, those places where your tires meet the road probably have good traction. However, if there is snow or ice between your tires and the road, you can have a very slippery situation. You’ll have a lot less traction or “grip” and will need to be very careful.

Here are some tips for winter driving:

Have your vehicle in good shape for winter. You may want to put winter emergency your vehicle.

supplies in

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Whatever the condition - smooth ice, packed, blowing or loose snow - drive with caution. If you have traction assist, keep the system on. It will improve your ability to accelerate when driving on a slippery road. But you can turn the traction system off if your vehicle ever gets stuck in sand, mud, ice or snow. See If You Are Stuck: In Sand, Mud, Ice or Snow on page 4-50. Even though your vehicle has a traction system, you’ll want to slow down and adjust your driving to the road conditions. See Traction Assist System (TAS) on page 4-9. If you don’t have a traction system, accelerate gently. Try not to break the gentle traction. If you accelerate too fast, the drive wheels will spin and polish the surface under the tires even more.

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What’s the worst time for this? “Wet ice.” Very cold snow or ice can be slick and hard to drive on. But wet ice can be even more trouble because it may offer the least traction of all. You can get wet ice when it’s about freezing (32°F; OOC) and freezing rain begins to fall. Try to avoid driving on wet ice until salt and sand crews can get there.

Your anti-lock brakes improve your vehicle’s stability when you make a hard stop on a slippery road. Even though you have an anti-lock braking system, you’ll want to begin stopping sooner than you would on dry pavement. See Braking on page 4-6.

Allow greater following distance on any slippery road. Watch for slippery spots. The road might be fine until you hit a spot that’s covered with ice. On an otherwise clear road, ice patches may appear in shaded areas where the sun can’t reach: around clumps of trees, behind buildings or under bridges. Sometimes the surface of a curve or an overpass may remain icy when the surrounding roads are clear. If you see a patch of ice ahead of you, brake before you are on it. Try not to brake while you’re actually on the ice, and avoid sudden steering maneuvers.

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If You’re Caught in a Blizzard

If you are stopped by heavy snow, you could be in a serious situation. You should probably stay with your vehicle unless you know for sure that you are near help and you can hike through the snow.Here are some things to do to summon help and keep yourself and your passengers safe: 0 Turn on your hazard flashers.

Tie a red cloth to your vehicle to alert police that you’ve been stopped by the snow.

0 Put on extra clothing or wrap a blanket around you. If

you have no blankets or extra clothing, make body insulators from newspapers, burlap bags, rags, floor mats - anything you can wrap around yourself or tuck under your clothing to keep warm.

You can run the engine to keep warm, but be careful.

our

Snow can trap el bust gases under vehicle. This can cause deadly CO (carbon monoxide) gas to get inside. CO could overcome you and kill you. You can’t see it or smell it, so you might not know it is in your vehicle. Clear away snow from around the base of your vehicle, especially any that is blocking your exhaust pipe. And check around again from time to time to be sure snow doesn’t collect there. Open a window just a little on the side of the vehicle that’s away from the wind. This will help keep CO out.

Run your engine only as long as you must. This saves fuel. When you run the engine, make it go a little faster than just idle. That is, push the accelerator slightly. This uses less fuel for the heat that you get and it keeps the battery charged. You will need a well-charged battery to restart the vehicle, and possibly for signaling later on with your headlamps. Let the heater run for a while.

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Then, shut the engine off and close the window almost all the way to preserve the heat. Start the engine again and repeat this only when you feel really uncomfortable from the cold. But do it as little as possible. Preserve the fuel as long as you can. To help keep warm, you can get out of the vehicle and do some fairly vigorous exercises every half hour or so until help comes.

If You Are Stuck: In Sand, Mud, Ice or Snow

In order to free your vehicle when it is stuck, you will need to spin the wheels, but you don’t want to spin your wheels too fast. The method known as “rocking” can help you get out when you’re stuck, but you must use caution.

If you let your tires spin at high speed, they can explode, and you or others could be injured. And, the transmission or other parts of the vehicle can overheat. That could cause an engine compartment fire or other damage. When you’re stuck, spin the wheels as little as possible. Don’t spin the wheels above 25 mph (55 km/h) as shown on the speedometer.

Notice: Spinning your wheels can destroy parts of your vehicle as well as the tires. If you spin the wheels too fast while shifting your transmission back and forth, you can destroy your transmission. For more information about using tire chains on your vehicle, see Tire Chains on page 5-82.

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Using the Recovery Hooks

Rocking Your Vehicle To Get It Out First, turn your steering wheel left and right. That will clear the area around your front wheels. If you have a four-wheel-drive vehicle, shift into 4HI. If your vehicle has the Traction Assist System, you should turn it off by pressing the TAS on/off button. Then shift back and forth between REVERSE (R) and a forward gear (or with a manual transmission, between FIRST (1) or SECOND (2) and REVERSE (R)), spinning the wheels as little as possible. Release the accelerator pedal while you shift, and press lightly on the accelerator pedal when the transmission is in gear. By slowly spinning your wheels in the forward and reverse directions, you will cause a rocking motion that may free your vehicle. If that doesn’t get you out after a few tries, you may need to be towed if your vehicle out. Or, you can use your recovery hooks has them. If you do need to be towed out, see Towing Your Vehicle on page 4-53.

Your vehicle may be equipped with recovery hooks. The hooks are provided at the front of your vehicle. You may need to use them if you’re stuck off-road and need to be pulled to some place where you can continue driving.

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These hooks, when used, are under a lot of force. Always pull the vehicle straight out. Never pull on the hooks at a sideways angle. The hooks could break off and you or others could be injured from the chain or cable snapping back.

Notice: Never use recovery hooks to tow the vehicle. Your vehicle could be damaged and it would not be covered by warranty.

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Towing

Towing Your Vehicle Consult your dealer or a professional towing service if you need to have your disabled vehicle towed. See Roadside Assistance Program on page 7-6. If you want to tow your vehicle behind another vehicle for recreational purposes (such as behind a motorhome), see ‘Recreational Vehicle Towing” following. Recreational Vehicle Towing Recreational vehicle towing means towing your vehicle behind another vehicle - such as behind a motorhome. The two most common types of recreational vehicle towing are known as “dinghy towing” (towing your vehicle will all four wheels on the ground) and (towing your vehicle with two wheels on two wheels up on a device known as a “dolly”). With the proper preparation and equipment, many vehicles can be towed in these ways. See Dinghy Towing and Dolly Towing following.

the ground and

“dolly towing”

Here are some important things to consider before you do recreational vehicle towing:

What’s the towing capacity of the towing vehicle? Be sure you read the tow vehicle manufacturer’s recommendations. How far will you tow? Some vehicles have restrictions on how far and how long they can tow. Do you have the proper towing equipment? See your dealer or trailering professional for additional advice and equipment recommendations. Is your vehicle ready to be towed? Just as you would prepare your vehicle for a long trip, you’ll want to make sure your vehicle is prepared to be towed. See Before Leaving on a Long Trip on page 4-42.

Dinghy Towing When towing your vehicle, turn the ignition to LOCK. Two-Wheel-Drive Vehicles Two-wheel-drive vehicles should not be towed with all four wheels on the ground. Two-wheel-drive transmissions have no provisions for internal lubrication while being towed. To properly tow these vehicles, they should be placed on a platform trailer with all four wheels off the ground.

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4. Shift the transfer case to NEUTRAL. See

Four-wheel Drive on page 2-35 for the proper procedure to select the neutral position for your vehicle.

5. Release the parking brake only after the vehicle

being towed is firmly attached to the towing vehicle.

6. Turn the ignition off.

Shifting a four-wheel-drive vehicle’s transfer case into NEUTRAL can cause your vehicle to roll even if the transmission is in Park (P) for an automatic transmission, or if your vehicle is in gear, for a manual transmission. You or others could be injured. Make sure the parking brake is firmly set before you shift the transfer case to NEUTRAL.

Four-Wheel-Drive Vehicles

Use the following procedure to tow your vehicle: 1. Firmly set the parking brake. 2. Shift an automatic transmission to PARK (P), or a

manual transmission to FIRST (1).

3. Securely attach the vehicle being towed to the tow

vehicle.

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Dolly Towing Two-Wheel-Drive Vehicles Two-wheel-drive vehicles should not be towed with the rear wheels on the ground. Two-wheel-drive transmissions have no provisions for internal lubrication while being towed. To properly tow these vehicles, they should be placed on a platform trailer with all four wheels off the ground. Four-Wheel-Drive Vehicles Use the following procedure to tow your vehicle: 1. Firmly set the parking brake. 2. Shift an automatic transmission to PARK (P), or a

manual transmission to FIRST (1).

3. Securely attach the vehicle being towed to the tow

vehicle.

4. Shift the transfer case to NEUTRAL. See

four-wheel Drive on page 2-35 for the proper procedure to select the neutral position for your vehicle.

5. Release the parking brake only after the vehicle

being towed is firmly attached to the towing vehicle.

6. -Arn the is

":ion off.

Shifting a four-wheel-drive vehicle's transfer case into NEUTRAL can cause your vehicle to roll even if the transmission is in Park (P) for an automatic transmission, or if your vehicle is in gear, for a manual transmission. You or others could be injured. Make sure the parking brake is firmly set before you shift the transfer case to NEUTRAL.

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Loading Your Vehicle

The CertificationDire label also tells you the maximum weights for the front and rear axles, called Gross Axle Weight Rating (GAWR). To find out the actual loads on your front and rear axles, you need to go to a weigh station and weigh your vehicle. Your dealer can help you with this. Be sure to spread out your load equally on both sides of the centerline. Never exceed the GVWR for your vehicle, or the GAWR for either the front or rear axle. The Certificationflire label also contains information about your Front Axle Reserve Capacity. See “Front Axle Reserve Capacity” later in this section. And, if YOU do have a heavy load, you should spread it out.

COLD TIRE PRESSURE

The CertificationDire label is found on the rear edge of the driver’s door or in the Incomplete Vehicle Document in the cab. The label shows the size of your original tires and the inflation pressures needed to obtain the gross weight capacity of your vehicle. This is called the GVWR (Gross Vehicle Weight Rating). The GVWR includes the weight of the vehicle, all occupants, fuel and cargo.

IL _he ---se of a sudden stop or c-...,.m, things carried in the bed of your truck could shift forward and come into the passenger area, injuring you and others. If you put things in the bed of your truck, you should make sure they are properly secured.

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Do not load your vehicle any heavier than the GVWR, or either the maximum front: or rear GAWR. If you do, parts on your vehicle can break, and it can change the way your vehicle handles. These could cause you to lose control and crash. Also, overloading can shorten the life of your vehicle.

Notice: Your warranty does not cover parts or components that fail because of overloading. This will help you decide how much cargo and installed equipment your truck can carry. Using heavier suspension components to get added durability might not change your weight ratings. Ask your dealer to help you load your vehicle the right way. If you put things inside your vehicle - like suitcases, tools, packages, or anything else - they go as fast as the vehicle goes. If you have to stop or turn quickly, or if there is a crash, they’ll keep going.

Things you put inside your vehicle can strike and injure people in a sudden stop or turn, or in a crash.

Put things in the trunk of your vehicle. In a trunk, put them as far forward as you can. Try to spread the weight evenly. Never stack heavier things, like suitcases, inside the vehicle so that some of them are above the tops of the seats. Don’t leave an unsecured child restraint in your vehicle. When you carry something inside the vehicle, secure it whenever you can.

There’s also important loading information for off-road driving in this manual. See “Loading Your Vehicle for Off-Road Driving” under Off-Road Driving with Your Four- Wheel- Drive Vehicle on page 4-2 1.

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Payload Payload capacity is the maximum load capacity that your vehicle can carry. Be sure to include the weight of the occupants as part of your load. If you added any accessories or equipment after your vehicle left the factory, remember to subtract the weight of these things from the payload. Your dealer can help you with this. Remember not to exceed the Gross Axle Weight Rating (GAWR) of the front or rear axle. See Loading Your Vehicle on page 4-56. 2-Tiered Loading By positioning four 2” x 6” wooden planks across the width of the pickup box, you can create an upper load platform. The planks must be inserted in the pickup box depressions. The length of the planks must allow for at least a 3/4 inch (2 cm) bearing surface on each end of the plank. When using this upper load platform, be sure the load is securely tied down to prevent it from shifting. The load’s center of gravity should be positioned in a zone over the rear axle. The zone is located in the area between the front of each wheel well and the rear of each wheel well. The center of gravity height must not extend above the top of the pickup box flareboard. Any load that extends beyond the vehicle’s taillamp area must be properly marked according to local laws and regulations.

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Remember not to exceed the Gross Axle Weight Rating (GAWR) of the front or rear axle. See Loading Your Vehicle on page 4-56. Add-on Equipment When you carry removable items, you may need to put a limit on how many people you carry inside your vehicle. Be sure to weigh your vehicle before you buy and install the new equipment. Notice: Your warranty does not cover parts or components that fail because of overloading. Remember not to exceed the Gross Axle Weight Rating (GAWR) of the front or rear axle. See Loading Your Vehicle on page 4-56.

*Equipment I Cross Toolbox and Carao I400 Ibs. (181 ka)

Maximum Weight 750 Ibs. (340 kg) Ladder Rack

and Carqo

I Side Boxes and Cargo

~~

~~

1 250 Ibs. per side

(1 13 ka per side)

* The combined weight for all rail-mounted equipment should not exceed 1,000 Ibs. (454 kg). A reinforcement kit for rail-mounted add-on equipment is recommended. See your dealer.

Q: How heavy can a snow plow safely be? A: The plow your vehicle can carry depends on many

things, such as: The options your vehicle came with, and the weight of those options,

e The weight and number of passengers you intend

to carry, The weight of items you’ve added to your vehicle, like a tool box or truck cap, The total weight of any additional cargo you intend to carry.

Say, for example, you have a 700 Ib. (31 8 kg) snow plow. The total weight of all occupants and cargo inside the cab should not exceed 300 Ib. (135 kg). This means that you may only be able to carry one passenger. But, even this may be too much if you’ve got other equipment already adding to the weight of your vehicle.

Adding a Snow Plow or Similar Equipment

Before installing a snow plow on your vehicle, here are some things you’ll need to know:

Notice: If your vehicle doesn’t have the snow plow prep package, adding a plow can damage your vehicle, and the repairs wouldn’t be covered by warranty. Unless your vehicle was built to carry a snow plow, don’t add one to your vehicle. If your vehicle has the snow plow option called RPO VYU (snow plow prep package), then the payload your vehicle can carry will be reduced when a snow plow is installed. Your vehicle can be damaged if either the front or rear axle ratings, or the GVW, are exceeded. Q: How do I know if my vehicle can handle a A: Some vehicles are built with a special package, called RPO VYU (snow plow prep package). If your vehicle has this option, you can add a plow to it, provided certain weights, such as the weights on the vehicle’s axles and the GVW, aren’t exceeded.

snow plow?

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I calculate it?

Q: What is front axle reserve capacity, and how do A: Front axle reserve capacity is the difference between your front GAWR and the front axle weight of your truck with full fuel and passengers. Basically, it’s the amount of weight you can add to your front axle before reaching your front GAWR.

The front axle reserve capacity for your vehicle can be found in the lower right corner of the CertificationRire label, as shown.

: TRUCK

COLD TIRE PRESSURE XXXKPA(XXPS1) XXXKPA(XXPS1)

E INFORMATION

F XXX * T u r n

COLD TIRE PRESSURE PRESSION A FROlD

xxxxxxxx(XXPS1) xxxxxxxx(XXPS1) I)AV/FXXX

T xxx

United States

Canada

Here are some guidelines for safely carrying a snow plow on your vehicle: 0 Make sure the weight on the front and rear axles

doesn’t exceed the axle rating for each. For the front axle, if more cargo or passengers must be carried, appropriate counter ballast must be installed rear of the rear axle. Counter ballast must be properly secured so it won’t move during driving. Follow the snow plow manufacturer’s recommendations regarding rear ballast. Rear ballast may be required to ensure a proper front and rear weight distribution ratio, even though the actual weight at the front axle may be less than the front axle rating. The snow plow manufacturer or installer can assist you in determining the amount of rear ballast required, to help make sure your snowplowhehicle combination does not exceed the GVW rating, the front and rear axle ratings, and the front and rear weight distribution ratio. The total vehicle must not exceed the GVW rating.

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In order to calculate the amount of weight any front accessory, such as a snow plow, is adding to the front axle, use the following formula:

(W x (A -t- W.B.)) /W.B.= Weight the accessory is adding to the front axle. Where: W = Weight of added accessory A = Distance that the accessory is in front of the front axle W.B. = Vehicle Wheelbase For example, adding a 700 Ib. (318 kg) snow plow actually adds more than 700 Ib. (318 kg) to the front axle. Using the formula, if the snow plow is 4 ft. (122 cm) in front of the front axle and the wheel base is 10 ft. (305 cm), then: W = 700 Ib. (318 kg) A = 4 ft. (122 cm) W.B. = 10 ft. (305 cm) (W X (A + W.B.))/W.B. = (700 X (4 + 10))/10 = 980 Ib. (445 kg) So, if your truck's front axle reserve capacity is more than 980 Ib. (445 kg), you could add the snow plow without exceeding the front GAWR.

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vehicle?

Q: What if I want to add heavier equipment to my A: You can add heavier equipment on the front of the vehicle if you compensate for it by carrying fewer passengers, less cargo, or by positioning cargo towards the rear. This has the effect of reducing the load on the front. However, the front GAWR, rear GAWR and the GVWR must never be exceeded.

On some vehicles equipped with certain front mounted equipment, such as a snow plow, it may be possible to load the front axle to the front GAWR but not have enough weight on the rear axle to have proper braking performance. If your brakes can’t work properly, you could have a crash. To help your brakes work properly when a snow plow is installed, always follow the snow plow manufacturer or installer’s recommendation for rear ballast to ensure a proper front and rear weight distribution ratio, even though theactual front weight may be less than the frontGAWR, and the total vehicle weight is less than the GVWR. Maintaining a proper front and rear weight distribution ratio is necessary to provide proper braking performance.

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Q: What is total vehicle reserve capacity? A: This is the difference between your GVWR and the weight of your truck with full fuel and passengers. It’s the amount of weight you can add to your vehicle before reaching your GVWR. Keep in mind that reserve capacity numbers are intended as a guide when selecting the amount of equipment or cargo your truck can carry. If you are unsure of your truck’s front, rear or total weight, go to a weigh station and weigh your vehicle. Your dealer can also help you with this.

See your dealer for additional advice and information about using a snow plow on your vehicle. Also, see Loading Your Vehicle on page 4-56.

Truck-Camper Loading Information This label is inside your glove box. It will tell you if your vehicle can carry a slide-in camper, how much of a load your vehicle can carry, and how to correctly spread out your load. Also, it will help you match the right slide-in camper to your vehicle. When you carry a slide-in camper, the total cargo load of your vehicle is the weight of the camper, plus

everything else added to the camper after it left the factory,

0 everything in the camper and

all the people inside.

The Cargo Weight Rating (CWR) is the maximum weight of the load your vehicle can carry. It doesn’t include the weight of the people inside. But, you can figure about 150 Ibs. (68 kg) for each seat. The total cargo load must not be more than your vehicle’s CWR.

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Refer to the Truck-Camper Loading Information label in glove box for dimensions A and B as shown in the following illustration.

w-A-I

Here is an example of proper truck and camper match:

Use the rear edge of the load floor for measurement purposes. The recommended location for the cargo center of gravity is at point C for the CWR. It is the point where the mass of a body is concentrated and, if suspended at that point, would balance the front and rear.

A. Camper Center of Gravity 6. Recommended Center of Gravity Location Zone The camper’s center of gravity should fall within the center of gravity zone for your vehicle’s cargo load. You must weigh any accessories or other equipment that you add to your vehicle. Then, subtract this extra weight from the CWR. This extra weight may shorten the center of gravity zone of your vehicle. Your dealer can help you with this. If your slide-in camper and its load weighs less than the CWR, the center of gravity zone for your vehicle may be larger.

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Your dealer can help you make a good vehicle-camper match. He’ll also help you determine your CWR. After you’ve loaded your vehicle and camper, drive to a weigh station and weigh the front and rear wheels separately. This will tell you the loads on your axles. The loads on the front and rear axles shouldn’t be more than either of the GAWRs. The total of the axle loads should not be more than the GVWR. Open your driver’s door and look at the CertificationRire label to find out your GAWR and GVWR. If you’ve gone over your weight ratings, move or take out some things until all the weight falls below the ratings. Of course, you should always tie down any loose items when you load your vehicle or camper. When you install and load your slide-in camper, check the manufacturer’s instructions. If you want more information on curb weights, cargo weights, Cargo Weight Rating and the correct center of gravity zone for your vehicle, your dealer can help you. Just ask for a copy of ”Consumer Information, Truck-Camper Loading.”

Trailer Recommendations

You must subtract your hitch loads from the CWR for your vehicle. Weigh your vehicle with the trailer attached, so that you won’t go over the GVWR or GAWR. If you are using a weight-distributing hitch, weigh the vehicle without the spring bars in place. You’ll get the best performance if you spread out the weight of your load the right way, and if you choose the correct hitch and trailer brakes. For more information, see Towing a Trailer on page 4-66.

Pickup Conversion to Chassis Cab

General Motors is aware that some vehicle owners may consider having the pickup box removed and a commercial or recreational body installed. Before you do so, first contact GM Customer Assistance for information on such conversions specific to this vehicle. Owners should be aware that, as manufactured, there are differences between a chassis cab and a pickup with the box removed which may affect vehicle safety. The components necessary to adapt a pickup to permit its safe use with a specialized body should be installed by a body builder in accordance with the information available from GM Customer Assistance. See Customer Assistance Offices on page 7-4.

4-65

Towing a Trailer

If YOL Jon’t use the correct equipment and drive properly, you can lose control when you pull a trailer. For example, if the trailer is too heavy, the brakes may not work well -- or even at all. You and your passengers could be seriously injured. Pull a trailer only if you have followed all the steps in this section. Ask your dealer for advice and information about towing a trailer with your vehicle.

Notice: Pulling a trailer improperly can damage your vehicle and result in costly repairs not covered by your warranty. To pull a trailer correctly, follow the advice in this part, and see your dealer for important information about towing a trailer with your vehicle. Additional rear axle maintenance is required for a vehicle used to tow a trailer. See “Scheduled Maintenance Services” in the Index.

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To identify the vehicle trailering capacity of your vehicle. you should read the information in Weight of the Trailer that appears later in this section. If yours was built with trailering options, as many are, it’s ready for heavier trailers. But trailering is different than just driving your vehicle by itself. Trailering means changes in handling, durability and fuel economy. Successful, safe trailering takes correct equipment, and it has to be used properly. That’s the reason for this part. In it are many time-tested, important trailering tips and safety rules. Many of these are important for your safety and that of your passengers. So please read this section carefully before you pull a trailer. If You Do Decide To Pull A Trailer If you do, here are some important points:

There are many different laws, including speed limit restrictions, having to do with trailering. Make sure your rig will be legal, not only where you live but also where you’ll be driving. A good source for this information can be state or provincial police. Consider using a sway control if your trailer will weigh less than 5,000 Ibs. (2 270 kg) for light duty vehicles, or less than 7,500 Ibs. (3 405 kg) for heavy duty vehicles. You should always use a sway control if your trailer will weigh more than these limits. You can ask a hitch dealer about sway controls.

0

Don’t tow a trailer at all during the first 500 miles (800 km) your new vehicle is driven. Your engine, axle or other parts could be damaged. Then, during the first 500 miles (800 km) that you tow a trailer, don’t drive over 50 mph (80 km/h) and don’t make starts at full throttle. This helps your engine and other parts of your vehicle wear in at the heavier loads. If you have an automatic transmission, you can tow in DRIVE (D). You may want to shift the transmission to THIRD (3) or, if necessary, a lower gear selection if the transmission shifts too often (e.g., under heavy loads and/or hilly conditions). If you have a manual transmission and you are towing a trailer, it’s better not to use the highest gear. See Tow/Hau/ Mode light on page 3-48.

Three important considerations have to do with weight:

the weight of the trailer, the weight of the trailer tongue

0 and the weight on your vehicle’s tires.

Tow/HauI Mode Tow/haul is a feature on automatic transmission equipped vehicles that assists when pulling a heavy trailer or a large or heavy load. The purpose of the tow/haul mode is to:

0 Reduce the frequency and improve the predictability of transmission shifts when pulling a heavy trailer or a large or heavy load.

0 Provide the same solid shift feel when pulling a heavy trailer or a large or heavy load as when the vehicle is unloaded. Improve control of vehicle speed while requiring less throttle pedal activity when pulling a heavy trailer or a large or heavy load.

Automatic transmission equipped vehicles are provided with a button at the end of the shift lever which when pressed enables tow/haul. When the button is pressed, a light on the instrument panel will illuminate to indicate that tow/haul has been selected. Tow/haul may be turned off by pressing the button again, at which time the indicator light on the instrument panel will turn off. The vehicle will automatically turn off tow/haul every time it is started.

4-67

Tow/haul is designed to be most effective when the vehicle and trailer combined weight is at least 75% of the vehicle’s Gross Combined Weight Rating (GCWR). See Weight of the Trailer later in the section. Tow/haul is most useful under the following driving conditions:

When pulling a heavy trailer or a large or heavy load through rolling terrain. When pulling a heavy trailer or a large or heavy load in stop and go traffic. When pulling a heavy trailer or a large or heavy load in busy parking lots where improved low speed control of the vehicle is desired.

Operating the vehicle in tow/haul when lightly loaded or with no trailer at all will not cause damage. However, there is no benefit to the selection of tow/haul when the vehicle is unloaded. Such a selection when unloaded may result in unpleasant engine and transmission driving characteristics and reduced fuel economy. Tow/haul is recommended only when pulling a heavy trailer or a large or heavy load.

Weight of the Trailer How heavy can a trailer safely be? It depends on how you plan to use your rig. For example, speed, altitude, road grades, outside temperature and how much your vehicle is used to pull a trailer are all important. And, it can also depend on any special equipment that you have on your vehicle. Use one of the following charts to determine how much your vehicle can weigh, based upon your vehicle model and options. Maximum trailer weight is calculated assuming the driver and one passenger are in the tow vehicle and it has all the required trailering equipment. The weight of additional optional equipment, passengers and cargo in the tow vehicle must be subtracted from the maximum trailer weight. Above the 5,000 Ibs. (2 268 kg) trailer rating, the handlinghrailering suspension is required on C-1500 models and the handlinghrailering or off -road suspension is required on K-1500 models.

4-68

I C-1500 Regular Cab Short Box (2WD)*

I Axle Ratio

Vehicle*

4300 V6 (Auto)

(Manual)

I 4800 V8 (Auto) I 4800

V8 (Manual)

3.08 3.42

z::;

3.42 3.73

i;;:

Maximum Trailer

Weight

GCWR

4,500 Ibs. (2 041 kg) 5,000 Ibs. (2 267kg)

9,000 Ibs. (4 086 kg) 9,500 Ibs. (4 313 kg)

(1 587 814 kg) kg)

4,000 3,500 Ibs. Ibs. (1 6,400 Ibs. (2 902 kg) 7,400 Ibs. (3 356 kg) 4,400 Ibs. (1 995 kg) 5,400 Ibs. (2 449 kg) 7,400 Ibs. (3 356 kg) 810 8,400 Ibs. (3 kg)

Ibs. kg)

(3 8,500 (3 632 859

8,000 kg) 1 1,000 Ibs. (4 994 kg) 12,000 Ibs. (5 448 kg) 9,000 Ibs. (4 086 kg) 10,000 Ibs. (4 540 kg) 12,000 Ibs. (5 448 kg) 13,000 Ibs. (5 902 kg)

Ibs.

* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,000 Ibs (454 kg). Fifth-wheel or gooseneck kingpin weight 15 percent to 25 percent of trailer weight up to 1,500 Ibs. (680 kg) maximum.

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I (C-I500 Extended Cab Short Box 2WD

I Axle Ratio

Vehicle"

Maximum Trailer Weight

GCWR

15 percent of trailer weight up to 1,000 Ibs (454 kg). Fifth-wheel or gooseneck kingpin weight 15 percent to 25 percent of trailer weight up to 1,500 Ibs. (680 kg) maximum. **Maximum 8,000 Ibs. (3 628 kg) for fifth-wheel or gooseneck. ***Maximum 7,500 Ibs. (3 401 kg) for fifth-wheel or gooseneck.

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I Axle

Ratio

Vehicle*

I C-1500 Crew Cab Short Box (2WD)* 1 6000 V8

wI4WS

Maximum Trailer Weight GCWR

8,200 Ibs. (3 719 kg) 10,200 Ibs. (4 626 kg

_ _ _ _ _ ~

9,900 Ibs. Ibs. (3 (4 490 583 kg) kg) 16,000 7,900

14,000 Ibs. (6 356 kg) 16,000 Ibs. (7 264 kg 14,000 Ibs. (6 356 kg)

Ibs. (7 264 kg

* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680kg). Fifth-wheel or gooseneck kingpin weight 15 percent to 25 percent of trailer weight up to 2,500 Ibs. (1 133 kg) maximum.

4-7 1

Vehicle* C-1500 Extended Cab Long Box (2WD)*

I Axle Ratio I Maximum Trailer Weight

I GCWR

4800 V8 (Auto)

4800 V8 (Manual)

3.42 3.73 3.42 3.73 3.42 3.73

5,900 Ibs. (2 676 kg) 6,900 Ibs. (3 129 kg) 3,900 Ibs. (1 769 kg) 4,900. (2 222 kg) 6,900 Ibs. (3 129 kg) 7,900 Ibs. (3 583 kg)

11,000 Ibs. (4 994 kg) 12,000 Ibs. (5 448 kg) 9,000 Ibs. (4 086 kg) 10,000 Ibs. (4 540 kg) 12,000 Ibs. (5 448 kg) 13,000 Ibs. (5 902 kg)

5300 V8 * Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,000 Ibs (454 kg). Fifth-wheel or gooseneck kingpin weight 15 percent to 25 percent of trailer weight up to 1,500 Ibs. (680 kg) maximum.

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‘*Maximum weight 7,700 Ibs. (3,492 kg) for fifth-wheel or gooseneck. ***Maximum weight 7,700 Ibs. (3,492 kg) for fifth-wheel or gooseneck.

-I

356 kg

Juz

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4-74

Vehicle* K-1500 Extended Cab Long Box (4WD)

I Axle Ratio

I Maximum Trailer Weight

I GCWR I 12,000 Ibs. (5 448 kg)

13,000 Ibs. (5 902 kg)

6,700 Ibs. (3 041 kg) 7,700 Ibs. (3 495 kg)**

4800 V8

5300 V8

4.10

* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,000 Ibs (454 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 1,500 Ibs. (680 kg) maximum. **Maximum weight 6,800 Ibs. (3 084 kg) for fifth-wheel and gooseneck.

1 Axle Ratio

I Maximum Trailer Weiaht

Vehicle* C-2500 LD (2WD** 6000 V8 * Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 2,500 Ibs. (1 133 kg) maximum.

8,700 Ibs. (3 946 kg) 10,700 Ibs. (4 853 kg)

(6 356 kg) 16,000 Ibs. (7 264 kg

3.73 14,000 Ibs. 4.10

I GCWR

4-75

** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch.

4-76

Vehicle* C-2500 Extended Cab Lon Box HD 2WD *

I Axle Ratio

I Maximum Trailer Weight

I GCWR

* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,000 Ibs. (1 360 kg) maximum. ** Limited to 12,000 Ibs. (5 443 kg) with weiqht distributing hitch.

4-77

I Axle Ratio

Vehicle* C-2500 Crew Cab Long Box HD (2WD) 6000 V8

81 00 V8

Maximum Trailer Weight

I GCWR

4.10 3.73 4.1 0 3.73

kg)

13,500 Ibs. (6 123 kg)** 15,500 Ibs. (7 030 kg) 15,200 Ibs. (6 894 kg)**

16,000 Ibs. (7 264 kg) 9,900 Ibs. (4 490 20,000 Ibs. (9 080 kg) 22,000 Ibs. (9 988 kg) 22,000 Ibs. (9 988 kg)

6.6L V8 Diesel * Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,000 Ibs. (1 360 kg) maximum. ** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch.

Vehicle" K-2500 LD (4WD)*

6000 V8

Axle Ratio

Maximum Trailer Weight

8,200 Ibs. (3 719 kg) 10,200 Ibs. (4 626 kg)

I GCWR I 14,000 Ibs. (6 356 kg)

16,000 Ibs. (7 264 kg)

* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 2,500 Ibs. (1 133 kg) maximum. ** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch.

4-78

Vehicle* K-2500 Regular Cab Long Box HD (4WD)*

I Axle Ratio I Maximum Trailer Weight

I GCWR

* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,000 Ibs. (1 360 kg) maximum. ** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch.

* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,000 Ibs. (1 360 kg) maximum. ** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch.

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* Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,000 Ibs. (1 360 kg) maximum. ** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch).

maximum. ** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch).

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C-3500 Crew Cab (2WD)*

4-81

The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and trailer including any passengers, cargo, equipment and conversions. The GCWR for your vehicle should not be exceeded. You can ask your dealer for our trailering information or advice, or you can write us at the address listed in your Warranty and Owner Assistance Information Booklet.

In Canada, write to: General Motors of Canada Limited Customer Communications Centre, 163-005 1908 Colonel Sam Drive Oshawa, Ontario LIH 8P7

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Weight of the Trailer Tongue The tongue load (A) of any trailer is an important weight to measure because it affects the total or gross weight of your vehicle. The Gross Vehicle Weight (GVW) includes the curb weight of the vehicle, any cargo you may carry in it, and the people who will be riding in the vehicle. And if you will tow a trailer, you must add the tongue load to the GVW because your vehicle will be carrying that weight, too. See Loading Your Vehicle on page 4-56 for more information about your vehicle’s maximum load capacity.

If you’re using a weight-carrying or a weight-distributing hitch, the trailer tongue weight (A) should be 10 percent to 15 percent of the total loaded trailer weight (6). Do not exceed the maximum allowable tongue weight for your vehicle. After you’ve loaded your trailer, weigh the trailer and then the tongue, separately, to see if the weights are proper. If they aren’t, you may be able to get them right simply by moving some items around in the trailer. Total Weight on Your Vehicle’s Tires Be sure your vehicle’s tires are inflated to the upper limit for cold tires. You’ll find these numbers on the Certification label at the rear edge of the driver’s door or see Loading Your Vehicle on page 4-56. Then be sure you don’t go over the GVW limit for your vehicle, including the weight of the trailer tongue. If you use a weight distributing hitch, make sure you don’t go over the rear axle limit before you apply the weight distribution spring bars.

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Hitches It’s important to have the correct hitch equipment. Crosswinds, large trucks going by and rough roads are a few reasons why you’ll need the right hitch. Here are some rules to follow:

If you use a step-bumper hitch, your bumper could be damaged in sharp turns. Make sure you have ample room when turning to avoid contact between the trailer and the bumper. If you’ll be pulling a trailer that, when loaded, will weigh more than 5,000 Ibs. (2 270 kg) be sure to use a properly mounted, weight-distributing hitch and sway control of the proper size. This equipment is very important for proper vehicle loading and good handling when you’re driving.

Safety Chains You should always attach chains between your vehicle and your trailer. Cross the safety chains under the tongue of the trailer to help prevent the tongue from contacting the road if it becomes separated from the hitch. Instructions about safety chains may be provided by the hitch manufacturer or by the trailer manufacturer. If you are towing a trailer up to 5,000 Ibs. (2 271 kg) with a factory-installed step bumper, you may attach the safety chains to the attaching points on the bumper. If you are towing a trailer up to your vehicle’s trailer rating limit you may attach the safety 4-84

chains to the attaching point on the hitch platform. If you are towing with an aftermarket hitch follow the trailer or hitch manufacturer’s recommendation for attaching safety chains. Always leave just enough slack so you can turn with your rig. Never allow safety chains to drag on the ground. Trailer Brakes If your trailer weighs more than 2,000 Ibs. (900 kg) loaded, then it needs its own brakes - and they must be adequate. Be sure to read and follow the instructions for the trailer brakes so you’ll be able to install, adjust and maintain them properly. Your trailer brake system can tap into the vehicle’s hydraulic brake system only if:

The trailer parts can withstand 3,000 psi (20 650 kPa) of pressure. The trailer’s brake system will use less than 0.02 cubic inch (0.3 cc) of fluid from your vehicle’s master cylinder. Otherwise, both braking systems won’t work well. You could even lose your brakes. If everything checks out this far, make the brake tap at the port on the master cylinder that sends the fluid to the rear brakes. But don’t use copper tubing for this. If you do, it will bend and finally break off. Use steel brake tubing.

Driving with a Trailer Towing a trailer requires a certain amount of experience. Before setting out for the open road, you’ll want to get to know your rig. Acquaint yourself with the feel of handling and braking with the added weight of the trailer. And always keep in mind that the vehicle you are driving is now a good deal longer and not nearly as responsive as your vehicle is by itself. Before you start, check the trailer hitch and platform (and attachments), safety chains, electrical connector, lamps, tires and mirror adjustment. If the trailer has electric brakes, start your vehicle and trailer moving and then apply the trailer brake controller by hand to be sure the brakes are working. This lets you check your electrical connection at the same time. During your trip, check occasionally to be sure that the load is secure, and that the lamps and any trailer brakes are stili working. While towing a trailer or when exposed to long periods of sunshine, the floor of the truck bed may become very warm. Avoid putting items in the truck bed that might be affected by high ambient temperatures.

Following Distance Stay at least twice as far behind the vehicle ahead as you would when driving your vehicle without a trailer. This can help you avoid situations that require heavy braking and sudden turns. Passing You’ll need more passing distance up ahead when you’re towing a trailer. And, because you’re a good deal longer, you’ll need to go much farther beyond the passed vehicle before you can return to your lane. Backing Up Hold the bottom of the steering wheel with one hand. Then, to move the trailer to the left, just move that hand to the left. To move the trailer to the right, move your hand to the right. Always back up slowly and, if possible. have someone guide you. Making Turns Notice: Making very sharp turns while trailering could cause the trailer to come in contact with the vehicle. Your vehicle could be damaged. Avoid making very sharp turns while trailering. When you’re turning with a trailer, make wider turns than normal. Do this so your trailer won’t strike soft shoulders, curbs, road signs, trees or other objects. Avoid jerky or sudden maneuvers. Signal well in advance.

4-85

Turn Signals When Towing a Trailer The arrows on your instrument panel will flash whenever you signal a turn or lane change. Properly hooked up, the trailer lamps will also flash, telling other drivers you’re about to turn, change lanes or stop. When towing a trailer, the arrows on your instrument panel will flash for turns even if the bulbs on the trailer are burned out. Thus, you may think drivers behind you are seeing your signal when they are not. It’s important to check occasionally to be sure the trailer bulbs are still working. Driving On Grades Reduce speed and shift to a lower gear before you start down a long or steep downgrade. If you don’t shift down, you might have to use your brakes so much that they would get hot and no longer work well. If you have an automatic transmission, you can tow in DRIVE (D). You may want to shift the transmission to lower gear selection if the transmission shifts too often (e.g., under heavy loads and/or hilly conditions).

You may also want to activate the tow/haul mode if the transmission shifts too often. See Tow/Haul Mode Light on page 3-48. If you have a 5-speed manual transmission and you are towing a trailer, it’s better not to use FIFTH (5) gear. Just drive in FOURTH (4) gear (or, as you need to, a lower gear). If you have a 6-speed manual transmission and you are towing a trailer, it’s better not to use SIXTH (6) gear. Drive in FIFTH (5) gear (or, as you need to, a lower gear). When towing at high altitude on steep uphill grades, consider the following: Engine coolant will boil at a lower temperature than at normal altitudes. If you turn your engine off immediately after towing at high altitude on steep uphill grades, your vehicle may show signs similar to engine overheating. To avoid this, let the engine run while parked (preferably on level ground) with the automatic transmission in PARK (P) (or the manual transmission out of gear and the parking brake applied) for a few minutes before turning the engine off. If you do get the overheat warning, see Engine Overheating on page 5-36.

4-86

You really should not park your vehicle, with a trailer attached, on a hill. If something goes i wrong, your rig could start to move. People

can be injured, and both your vehicle and the trailer can be damaged.

But if you ever have to park your rig on a hill, here’s how to do it: 1. Apply your regular brakes, but don’t shift into

PARK (P) yet for an automatic transmission, or into gear for a manual transmission.

2. Have someone place chocks under the trailer

wheels.

3. When the wheel chocks are in place, release the regular brakes until the chocks absorb the load.

4. Reapply the regular brakes. Then apply your parking brake and shift into PARK (P) for an automatic transmission, or REVERSE (R) for a manual transmission.

5. If you have a four-wheel-drive vehicle, be sure the

transfer case is in a drive gear and not in NEUTRAL. 3elease the re

lar brakes.

It can be dangerous to get out of your vt cle the shift lever is not fully in PARK (P) with the parking brake firmly set. Your vehicle can roll. If you have left the engine running, the vehicle can move suddenly. You or others could be injured. To be sure your vehicle won’t move, even when you’re on fairly level ground, use the steps that follow. Always put the shift lever fully the parking brake firmly set. If the transfer case on four-wheel drive vehicles is in NEUTRAL, your vehicle will be free to roll, even if your shift lever is in PARK (P). So, be sure the transfer case NEUTRAL.

is in a drive gear -- not in

in PARK (P) with

4-87

When You Are Ready to Leave After Parking on a Hill 1. Apply your regular brakes and hold the pedal down

while you:

start your engine, shift into a gear, and release the parking brake.

2. Let up on the brake pedal. 3. Drive slowly until the trailer is clear of the chocks. 4. Stop and have someone pick up and store the

chocks.

Maintenance When Trailer Towing Your vehicle will need service more often when you’re pulling a trailer. See the Maintenance Schedule for more on this. Things that are especially important in trailer operation are automatic transmission fluid (don’t overfill), engine oil, axle lubricant, belt, cooling system and brake system. Each of these is covered in this manual, and the index will help you find them quickly. If you’re trailering, it’s a good idea to review these sections before you start your trip. Check periodically to see that all hitch nuts and bolts are tight.

4-88

Trailer Wiring Harness Your vehicle is equipped with one of the following wiring harnesses for towing a trailer or hauling a slide-in camper. Basic Trailer Wiring All regular, extended cab crew cab pickups have a six-wire trailer towing harness.

The six-wire harness is located at the rear of the vehicle and is tied to the vehicle’s frame. The harness requires the installation of a trailer-wiring harness connector, which is available through your dealer.

Trailer Wiring Harness Package

The six-wire harness contains the following trailer circuits: 0 Yellow: Left Stopnurn Signal

Dark Green: Right Stop/Turn Signal

0 Brown: Taillamps

White: Ground

0 Light Green: Back-up Lamps

Light Blue: Center High-Mounted Stoplamp (CHMSL)

If you need to upgrade your trailer wiring harness, an additional 2-wire harness and 7 pin universal trailer connector are available from your dealer.

Your pickup may be equipped with the eight-wire trailer towing harness. This harness with a seven-pin universal trailer connector is attached to a bracket on the hitch platform.* * The Center High-Mounted Stoplamp (CHMSL) wire is tied next to the trailer wiring harness for use with a trailer, slide-in camper or cap.

4-89

The eight-wire harness contains the following trailer circuits:

Yellow: Left Stop/Turn Signal Dark Green: Right Stopnurn Signal

0 Brown: Taillamps White: Ground

4 Light Green: Back-up Lamps 0 Light Blue: CHMSL 0 Red: Battery Feed 0 Dark Blue: Trailer Brake If your trailer is equipped with electric brakes, you can get a jumper harness (electric trailer brake control) with a trailer battery feed fuse from your dealer. If you need to tow a light-duty trailer with a standard four-way round pin connector you can also get an adapter from your dealer.

Camper/Fifth-Wheel Trailer Wiring Package The eight-wire camper harness is located under the front edge of the pickup box on the driver’s side of the vehicle, attached to the frame bracket. A connector will have to be added to the wiring harness which connects to the camper. The eight-wire harness contains the following camper/trailer circuits:

Yellow: Left Stopnurn Signal Dark Green: Right Stopnurn Signal Brown: Taillamps White: Ground Light Green: Back-up Lamps Light Blue: Center High-Mounted Stoplamp (CHMSL) Red: Battery Feed Dark Blue: Trailer Brake

A jumper harness for an electric trailer brake controller and a trailer battery feed fuse are included with this trailering package. (See lnstrument Panel Jumper Wiring Harness later in this section.)

4-90

A

If your vehicle has this provision, this relay will be located on the passenger’s side of the vehicle, next to the auxiliary battery.

If your vehicle is equipped with the “Heavy-Duty Trailering” option, please refer to Heavy-Duty Trailer Wiring Package, earlier in this section. When the camper-wiring harness is ordered without the heavy-duty trailering package, an eight-wire harness with a seven-pin connector and separate CHMSL connector are located at the rear of the vehicle and are tied to the vehicle’s frame. Auxiliary Battery The auxiliary battery provision can be used to supply electrical power to additional equipment that you may choose to add, such as a slide-in camper.

When using this provision, connection should only be made to the upper stud (A) of the relay. Do not make connections to the lower stud (B) of the relay. The auxiliary battery circuit is protected by a megafuse located behind the auxiliary battery. Be sure to follow the proper installation instructions that are included with any electrical equipment that you install. Notice: When using the auxiliary battery provision, the electrical load must not exceed 30 amps. Always turn off any electrical equipment when not in use. Leaving electrical equipment on for extended periods will drain your battery.

4-9 1

Power Winches If you wish to use a power winch on your vehicle, only use it when your vehicle is stationary or anchored. Power Take-Off (PTO) Before using a PTO, refer to the manufacturer’s or installer’s instructions. To engage a PTO on a vehicle with a manual transmission do the following:

1. Hold the clutch pedal down. 2. Set the parking brake. 3. Shift the transmission into NEUTRAL (N). 4. Engage the PTO. Refer to the manufacturer’s or

installer’s for instructions on electrically engaged PTOs.

5. For mobile operations, shift the transmission into the gear you want, apply the regular brakes and release the parking brake. For stationary operations, leave the parking brake applied.

6. Release the clutch and regular brakes as you normally would. When the clutch is released, the PTO will start.

7. Turn the PTO rotary switch to ON.

To engage a PTO on a vehicle with an automatic transmission do the following: 1. For stationary use shift the transmission into

PARK (P).

2. Turn the PTO rotary switch ON. 3. If the engine speed is below the PTO engage

speed limit, the PTO will start. The blinking LED on the PTO control switch indicates PTO engage is requested. When PTO engages the LED will switch from blinking to a steady light.

To use PTO speed control in Preset Mode (Factory Setting) do the following: 1. Engage the PTO 2. Select PARK (P) or NEUTRAL (N) range. Apply the parking brake if NEUTRAL (N) is selected. Torque Converter Clutch (TCC) is not available in NEUTRAL (N) and is available only in PARK ( P) when engine speed is above 1,100 rpm.

3. Make sure your foot is off the brake pedal (and off

the clutch on vehicles equipped with a manual transmission).

4. Select the desired engine speed for PTO operation.

Read the following preset mode information regarding operation.

4-92

To use PTO speed control in variable mode (while stationary) do the following: 1. Engage the PTO. 2. Vehicle speed must be less than 5 mph. 3. Make sure your foot is off the brake pedal (and off

the clutch for vehicles equipped with a manual transmission).

4. Select the desired engine speed by using the foot

pedal, and select SET on the PTO switch or the cruise control.

Preset Mode: PTO speed control mode is used for stationary applications. (PTO will remain engaged while mobile in the preset mode, however PTO set and resume speed controls will be inoperative). This mode provides a default standby speed of 800 or 850 rpm (depending on the engine/transmission combination) and two default PTO control speeds which follow: 1. PTO Set Speed of 1,250 rpm, or 2. PTO Resume Speed of 1,700 rpm. Please note that the standby speed (800/850 rpm) is not to be used as a PTO control speed. Vehicles not equipped with cruise control will not have the resume speed capability. To use PTO speed control in variable mode (while mobile) do the following: 1. Engage the PTO. 2. Vehicle speed must be greater than 5 mph. 3. Make sure your foot is off the brake pedal (and off

the clutch for vehicles equipped with a manual transmission).

4. Select the desired engine speed by using the foot

pedal, and select SET on the PTO switch or the cruise control.

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Variable Mode: PTO speed control mode can be used for both stationary and mobile applications. This mode allows PTO to be controlled in a fashion similar to how cruise control sets vehicle speed. The operator can set to an rpm (between 800 and 2,200) with the cruise control feature or with the SET position on the PTO switch. The operator is then able to increase rpm in increments of 100, or ”tap up” with the resume position on the cruise control. Or, the operator can decrease rpm in increments of 100 with the SET switch on the PTO or the cruise control. Vehicles not equipped with cruise control will not have the “tap up” capability.. All engine speed values listed above are factory preset values. With the exception of the TCC lockup speed (1 ,I 00 rpm) and the “tap” increment (I00 rpm), all of these values are programmable and can be adjusted by your dealer or body upfitter. If the PTO software settings do not match the settings shown here, then they may have already been altered in order to satisfy the requirements of the installed PTO system and body equipment.

Step-Bumper Pad Your vehicle has a rear step bumper with a rear step pad at the center of the bumper.

If you will be using the bumper to tow a trailer, and your step-bumper has three cutout circles, you must push out the center cutout circle to install the trailer ball.

If your step-bumper has only one cutout circle, you will have to cut out the circle, then remove it to install the trailer ball.

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5 Service and Appearance Care

Service ............................................................ 5.3 ......................... 5-4

Doing Your Own Service Work Adding Equipment to the Outside of Your

Vehicle ...................................................... 5-4 Fuel ................................................................ 5-5 Gasoline Octane ............................................ 5-5 Gasoline Specifications .................................... 5-5 California Fuel ............................................... 5-6 Additives ....................................................... 5-6 Fuels in Foreign Countries ............................... 5-7 Filling Your Tank ............................................ 5-7 Filling a Portable Fuel Container ....................... 5-9 Checking Things Under the Hood ...................... 5-10 Hood Release ............................................. -5-1 0 Engine Compartment Overview ...................... 5-12 Engine Oil ................................................... 5-17 Engine Air Cleaner/Filter ................................ 5-23 Automatic Transmission Fluid

(Except Allison Transmission) ................... 5-25

Automatic Transmission Fluid

(Allison Transmission) ............................ 5-28 Manual Transmission Fluid ......................... 5-31 Hydraulic Clutch ........................................... 5-32 Engine Coolant ............................................. 5-33 Coolant Surge Tank Pressure Cap .................. 5-36

Engine Overheating ....................................... 5.36 Cooling System ............................................ 5.39 Engine Fan Noise ......................................... 5.44 Power Steering Fluid ..................................... 5.44 Windshield Washer Fluid ................................ 5.46 Brakes ........................................................ 5.47 Battery ..................................................... 5.50 Jump Starting ............................................ 5-51 Rear Axle ....................................................... 5.57 Four-wheel Drive ............................................ 5.58 Noise Control System ..................................... 5.60

Tampering with Noise Control System

Prohibited ................................................. Bulb Replacement .........................................

5-60 -5-61 Halogen Bulbs .............................................. 5.6 1 Headlamps .................................................. 5.61 Front Turn Signal, Sidemarker and Daytime 5-63 Roof Marker Lamps ...................................... 5.64 Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp ............................................. Pickup Box Identification and Fender Marker

Running Lamps .........................................

5.66

Lamps ..................................................... 5.67 Taillamps ..................................................... 5.67 Replacement Bulbs ....................................... 5.70

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Section 5

Service and Appearance Care

Windshield Wiper Blade Replacement .............. 5-71 Tires .............................................................. 5-72 Inflation .. Tire Pressure ................................ 5-73 Dual Tire Operation ..................................... -5-74 Tire Inspection and Rotation ........................... 5-74 When It Is Time for New Tires ....................... 5-77 Buying New Tires ......................................... 5-78 Uniform Tire Quality Grading .......................... 5-79 Wheel Alignment and Tire Balance .................. 5-80 Wheel Replacement ...................................... 5-80 Tire Chains .................................................. 5-82 If a Tire Goes Flat ....................................... 5-83 Changing a Flat Tire ..................................... 5-84 Appearance Care .......................................... 5-102 Cleaning the Inside of Your Vehicle ............... 5-102 Care of Safety Belts .................................... 5-105 Weatherstrips ............................................. 5.105

Cleaning the Outside of Your Vehicle ............. 5.105 Sheet Metal Damage ................................... 5.107 Finish Damage ...................... .......... 5-107 Underbody Maintenance ............................... 5-108 Chemical Paint Spotting ............................... 5-108 GM Vehicle Care/Appearance Materials .......... 5-108 Vehicle Identification ..................................... 5.110 Vehicle Identification Number (VIN) ................ 5-1 10 Service Parts Identification Label ................... 5-110 Electrical System .......................................... 5-1 11 Add-on Electrical Equipment ......................... 5-1 11 Windshield Wiper Fuses ............................... 5-1 11 Power Windows and Other Power Options ...... 5.111 Fuses and Circuit Breakers .......................... 5-1 11 Capacities and Specifications ....................... 5-120 Capacities and Specifications ........................ 5.120 Normal Maintenance Replacement Parts ........ -5-1 24

5-2

Service Your dealer knows your vehicle best and wants you to be happy with it. We hope you’ll go to your dealer for all your service needs. You’ll get genuine GM parts and GM-trained and supported service people. We hope you’ll want to keep your GM vehicle all GM. Genuine GM parts have one of these marks:

5-3

Doing Your Own Service Work If you want to do some of your own service work, you’ll want to use the proper service manual. It tells you much more about how to service your vehicle than this manual can. To order the proper service manual, see Service Publications Ordering information on page 7-10. Your vehicle has an air bag system. Before attempting to do your own service work, see Servicing Your Air Bag-Equipped Vehicle on page 1 - 77. You should keep a record with all parts receipts and list the mileage and the date of any service work you Derform. See Part E: Maintenance Record on pane 6-21.

You can be injured and your hic could be damaged if you try to do service work on a vehicle without knowing enough about it.

Be sure you have sufficient knowledge, experience, the proper replacement parts and tools before you attempt any vehicle maintenance task.

CAUTION:

(Continued)

5-4

. d s , bolts and

Be -Jre to use the pr,,er other fasteners. “English” and “metric” fasteners can be easily confused. If you use the wrong fasteners, parts can later break or fall off. You could be hurt.

Adding Equipment to the Outside of Your Vehicle Things you might add to the outside of your vehicle can affect the airflow around it. This may cause wind noise and affect windshield washer performance. Check with your dealer before adding equipment to the outside of your vehicle.

Fuel If your vehicle has a diesel engine, see “Diesel Fuel Requirements and Fuel System” in the Diesel Engine Supplement. For vehicles with gasoline engines, please read this. Gasoline Octane Use regular unleaded gasoline with a posted octane of 87 or higher. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine. A little pinging noise when you accelerate or drive uphill is considered normal. This does not indicate a problem exists or that a higher-octane fuel is necessary. If you are using 87 octane or higher-octane fuel and hear heavy knocking, your engine needs service.

Gasoline Specifications It is recommended that gasoline meet specifications which were developed by the American Automobile Manufacturers Association and endorsed by the Canadian Vehicle Manufacturers Association for better vehicle performance and engine protection. Gasoline meeting these specifications could provide improved driveability and emission control system performance compared to other gasoline.

In Canada, look for the “Auto Makers’ Choice” label on the pump.

Canada Only

5-5

General Motors recommends that you use these gasolines, particularly if they comply with the specifications described earlier. Notice: Your vehicle was not designed for fuel that contains methanol. Don’t use fuel containing methanol. It can corrode metal parts in your fuel system and also damage the plastic and rubber parts. That damage wouldn’t be covered under your warranty. Some gasolines that are not reformulated for low emissions may contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT); ask the attendant where you buy gasoline whether the fuel contains MMT. General Motors does not recommend the use of such gasolines. Fuels containing MMT can reduce the life of spark plugs and the performance of the emission control system may be affected. The malfunction indicator lamp may turn on. If this occurs, return to your authorized GM dealer for service.

California Fuel If your vehicle is certified to meet California Emission Standards (see the underhood emission control label), it is designed to operate on fuels that meet California specifications. If this fuel is not available in states adopting California emissions standards, your vehicle will operate satisfactorily on fuels meeting federal specifications, but emission control system performance may be affected. The malfunction indicator lamp may turn on (see Malfunction Indicator Lamp on page 3-44) and your vehicle may fail a smog-check test. If this occurs, return to your authorized GM dealer for diagnosis. If it is determined that the condition is caused by the type of fuel used, repairs may not be covered by your warranty. Additives To provide cleaner air, all gasolines in the United States are now required to contain additives that will help prevent engine and fuel system deposits from forming, allowing your emission control system to work properly. You should not have to add anything to your fuel. Gasolines containing oxygenates, such as ethers and ethanol, and reformulated gasolines may be available in your area to contribute to clean air.

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Fuels in Foreign Countries

If you plan on driving in another country outside the United States or Canada, the proper fuel may be hard to find. Never use leaded gasoline or any other fuel not recommended in the previous text on fuel. Costly repairs caused by use of improper fuel wouldn’t be covered by your warranty. To check the fuel availability, ask an auto club, or contact a major oil company that does business in the country where you’ll be driving.

Filling Your Tank

Fuel v or is highly flammable. It burns violently, and that can cause very bad injuries. Don’t smoke if you’re near fuel or refueling your vehicle. Keep sparks, flames and smoking materials away from fuel.

The fuel cap is located behind a hinged door on the driver’s side of the vehicle.

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If you get fuel on yourself and tnen something ignites it, you could be badly burned. Fuel can spray out on you if you open the fuel cap too quickly. This spray can happen if your tank nearly full, and is more likely in hot weather. Open the fuel cap slowly and wait for any “hiss” noise to stop. Then unscrew the cap all the way.

is

Be careful not to spill gasoline. Clean gasoline from painted surfaces as soon as possible. See Cleaning the Outside of Your Vehicle on page 5- 105. When you put the fuel cap back on, turn it to the right (clockwise) until you hear a clicking sound. Make sure you fully install the cap. The diagnostic system can determine if the fuel cap has been left off or improperly installed. This would allow fuel to evaporate into the atmosphere. See Malfunction Indicator Lamp on page 3-44. Notice: If you need a new fuel cap, be sure to get the right type. Your dealer can get one for you. If you get the wrong type, it may not fit properly. This may cause your malfunction indicator lamp to light and may damage your fuel tank and emissions See “Malfunction Indicator Lamp” in the Index.

system.

While refueling, hang the fuel cap by the tether using the hook located on the inside of the filler door. To remove the fuel cap, turn it slowly to the left (counterclockwise).

5-8

Filling a Portable Fuel Contain-

.r