2010 Chevrolet Silverado Owners Manual

5.3L V8 engine (VIN Code 3), the 6.0L V8 engine (VIN Code J), or the 6.2L V8 engine (Code 2), you can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). See Fuel on page 6‑6 . In all other engines, use only the unleaded gasoline described under Gasoline Octane on page 6‑7. Only vehicles that have the 5.3L V8 engine (Code 0), the 5.3L V8 engine (VIN Code 3), the 6.0L V8 engine (VIN Code J), or the 6.2L V8 engine (Code 2) can use 85% ethanol fuel (E85). We encourage the use of E85 in vehicles that are designed to use it. The ethanol in E85 is a “renewable” fuel, meaning it is made from renewable sources such as corn and other crops.

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Many service stations will not have an 85% ethanol fuel (E85) pump available. The U.S. Department of Energy has an alternative fuels website (www.eere.energy.gov/ afdc/infrastructure/locator.html) that can help you find E85 fuel. Those stations that do have E85 should have a label indicating ethanol content. Do not use the fuel if the ethanol content is greater than 85%. At a minimum, E85 should meet ASTM Specification D 5798. By definition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%. Filling the fuel tank with fuel mixtures that do not meet ASTM specifications can affect driveability and could cause the malfunction indicator lamp to come on.

To ensure quick starts in the wintertime, the E85 fuel must be formulated properly for your climate according to ASTM specification D 5798. If you have trouble starting on E85, it could be because the E85 fuel is not properly formulated for your climate. If this happens, switching to gasoline or adding gasoline to the fuel tank can improve starting. For good starting and heater efficiency below 0°C (32°F), the fuel mix in the fuel tank should contain no more than 70% ethanol. It is best not to alternate repeatedly between gasoline and E85. If you do switch fuels, it is recommended that you add as much fuel as possible — do not add less than 11 L (three gallons) when refueling. You should drive the vehicle immediately after refueling for at least 11 km (seven miles) to allow the vehicle to adapt to the change in ethanol concentration. E85 has less energy per gallon than gasoline, so you will need to refill the fuel tank more often when using E85 than when you are using gasoline. See Filling the Tank on page 6‑11.

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Notice: Some additives are not compatible with E85
fuel and can harm the vehicle's fuel system. Do not add anything to E85. Damage caused by additives would not be covered by the vehicle warranty. Notice: This vehicle was not designed for fuel that contains methanol. Do not use fuel containing methanol. It can corrode metal parts in the fuel system and also damage plastic and rubber parts. That damage would not be covered under the vehicle warranty. Fuels in Foreign Countries If you plan on driving in another country outside the United States or Canada, the proper fuel might 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 would not be covered by the vehicle warranty. To check the fuel availability, ask an auto club, or contact a major oil company that does business in the country where you will be driving.

Filling the Tank If the vehicle has the DURAMAX Diesel engine, see the DURAMAX Diesel manual for more information.

{ WARNING:

Fuel vapor burns violently and a fuel fire can cause bad injuries. To help avoid injuries to you and others, read and follow all the instructions on the fuel pump island. Turn off the engine when refueling. Do not smoke near fuel or when refueling the vehicle. Do not use cellular phones. Keep sparks, flames, and smoking materials away from fuel. Do not leave the fuel pump unattended when refueling the vehicle. This is against the law in some places. Do not re-enter the vehicle while pumping fuel. Keep children away from the fuel pump; never let children pump fuel.

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{ WARNING:

Fuel can spray out on you if you open the fuel cap too quickly. If you spill fuel and then something ignites it, you could be badly burned. This spray can happen if the tank is 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.

If the vehicle is a dual fuel tank chassis cab model, and it runs out of fuel, refuel the front fuel tank first to ensure a quick restart. Be careful not to spill fuel. Do not top off or overfill the tank and wait a few seconds after you have finished pumping before removing the nozzle. Clean fuel from painted surfaces as soon as possible. See Washing Your Vehicle on page 6‑113. When replacing the fuel cap, turn it clockwise until it clicks. It will require more effort to turn the fuel cap on the last turn as you tighten it. Make sure the cap is fully installed. 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 4‑41.

The tethered fuel cap is located behind a hinged fuel door on the driver side of the vehicle. If the vehicle has E85 fuel capability, the fuel cap will be yellow and state that E85 or gasoline can be used. See Fuel E85
(85% Ethanol) on page 6‑9. To remove the fuel cap, turn it slowly counterclockwise.

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The TIGHTEN GAS CAP message displays on the Driver Information Center (DIC) if the fuel cap is not properly installed. See DIC Warnings and Messages on page 4‑63 for more information.

Filling a Portable Fuel Container

{ WARNING:

{ WARNING:

If a fire starts while you are refueling, do not remove the nozzle. Shut off the flow of fuel by shutting off the pump or by notifying the station attendant. Leave the area immediately.

Notice: If you need a new fuel cap, be sure to get the right type. Your dealer/retailer can get one for you. If you get the wrong type, it may not fit properly. This may cause the malfunction indicator lamp to light and may damage the fuel tank and emissions system. See Malfunction Indicator Lamp on page 4‑41.

Never fill a portable fuel container while it is in the vehicle. Static electricity discharge from the container can ignite the fuel vapor. You can be badly burned and the vehicle damaged if this occurs. To help avoid injury to you and others: . Dispense fuel only into approved containers. . Do not fill a container while it is inside a

vehicle, in a vehicle's trunk, pickup bed, or on any surface other than the ground.

. Bring the fill nozzle in contact with the inside

of the fill opening before operating the nozzle. Contact should be maintained until the filling is complete.

. Do not smoke while pumping fuel. . Do not use a cellular phone while

pumping fuel.

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Checking Things Under the Hood

{ WARNING:

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

{ WARNING:

Things that burn can get on hot engine parts and start a fire. These include liquids like fuel, oil, coolant, brake fluid, windshield washer and other fluids, and plastic or rubber. You or others could be burned. Be careful not to drop or spill things that will burn onto a hot engine.

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Hood Release To open the hood:

1. Pull the handle with this symbol on it. It is located inside the vehicle to the left of the brake pedal.

2. Then go to the front of the vehicle and locate the

secondary hood release. This is located under the hood, near the center of the grille.

3. Push the secondary hood release to the right. 4. Lift the hood.

Before closing the hood, be sure all the filler caps are on properly. Then bring the hood from full open to within 6 inches (152 mm) from the closed position, pause, then push the front center of the hood with a swift, firm motion to fully close the hood.

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Engine Compartment Overview If the vehicle has a diesel engine and/or an Allison Transmission, see the maintenance schedule section in the DURAMAX® Diesel manual.

5.3 L V8 Engine (4.3 L V6 Engine, 4.8 L V6 Engine, 6.0 L V8 Engine and 6.2 L V8 Engine similar):

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A. Engine Air Cleaner/Filter on page 6‑21. B. Coolant Surge Tank and Pressure Cap. See

Cooling System on page 6‑30.

C. Positive (+) Terminal. See Jump Starting on

page 6‑44 .

D. Battery on page 6‑43. E. Engine Oil Fill Cap. See “When to Add Engine Oil”

under Engine Oil on page 6‑18.

F. Automatic Transmission Dipstick. See “Checking

the Fluid Level” under Automatic Transmission Fluid (4-Speed Transmission) on page 6‑23 or Automatic Transmission Fluid (6-Speed Transmission) on page 6‑26.

G. Remote Negative (−) Terminal (Out of View). See

Jump Starting on page 6‑44.

H. Engine Oil Dipstick (Out of View). See “Checking

Engine Oil” under Engine Oil on page 6‑18.

I. Engine Cooling Fan. See Cooling System on

page 6‑30 .

J. Power Steering Fluid Reservoir. See Power

Steering Fluid on page 6‑37.

K. Brake Master Cylinder Reservoir. See “Brake

Fluid” under Brakes on page 6‑39.

L. Underhood Fuse Block on page 6‑122. M. Windshield Washer Fluid Reservoir. See “Adding Washer Fluid” under Windshield Washer Fluid on page 6‑38 .

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Engine Oil For diesel engine vehicles, see “Engine Oil” in the DURAMAX® Diesel manual. Checking Engine Oil It is a good idea to check the engine oil level at each fuel fill. In order to get an accurate reading, the oil must be warm and the vehicle must be on level ground. The engine oil dipstick handle is a yellow loop. See Engine Compartment Overview on page 6‑16 for the location of the engine oil dipstick.

1. Turn off the engine and give the oil several minutes to drain back into the oil pan. If this is not done, the oil dipstick might not show the actual level.

2. Pull out the dipstick and clean it with a paper towel or cloth, then push it back in all the way. Remove it again, keeping the tip down, and check the level.

When to Add Engine Oil

If the oil is below the cross-hatched area at the tip of the dipstick, add at least one liter/quart of the recommended oil. This section explains what kind of oil to use. For engine oil crankcase capacity, see Capacities and Specifications on page 6‑126. Notice: Do not add too much oil. If the engine has so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, the engine could be damaged.

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See Engine Compartment Overview on page 6‑16
for the location of the engine oil fill cap.

. American Petroleum Institute (API) starburst

symbol

Oils meeting these requirements should have the starburst symbol on the container. This symbol indicates that the oil has been certified by the American Petroleum Institute (API).

Add enough oil to put the level somewhere in the proper operating range. Push the dipstick all the way back in when through. What Kind of Engine Oil to Use Look for three things:

. GM6094M

Use only an oil that meets GM Standard GM6094M. . SAE 5W-30

SAE 5W-30 is best for the vehicle. These numbers on an oil container show its viscosity, or thickness. Do not use other viscosity oils such as SAE 20W-50.

Notice: Use only engine oil identified as meeting GM Standard GM6094M and showing the American Petroleum Institute Certified For Gasoline Engines starburst symbol. Failure to use the recommended oil can result in engine damage not covered by the vehicle warranty. Cold Temperature Operation If in an area of extreme cold, where the temperature falls below −29°C (−20°F), use either an SAE 5W-30
synthetic oil or an SAE 0W-30 engine oil. Both provide easier cold starting for the engine at extremely low temperatures. Always use an oil that meets the required specification, GM6094M. See “What Kind of Engine Oil to Use” for more information.

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Engine Oil Additives / Engine Oil Flushes Do not add anything to the oil. The recommended oils with the starburst symbol that meet GM Standard GM6094M are all that is needed for good performance and engine protection. Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty. Engine Oil Life System When to Change Engine Oil This vehicle has a computer system that indicates when to change the engine oil and filter. This is based on engine revolutions and engine temperature, and not on mileage. Based on driving conditions, the mileage at which an oil change is indicated can vary considerably. For the oil life system to work properly, the system must be reset every time the oil is changed. On some vehicles, when the system has calculated that oil life has been diminished, a CHANGE ENGINE OIL SOON message comes on to indicate that an oil change is necessary. See DIC Warnings and Messages on page 4‑63 . Change the oil as soon as possible within the next 1 000 km (600 miles). It is possible that,

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if driving under the best conditions, the oil life system might not indicate that an oil change is necessary for over a year. However, the engine oil and filter must be changed at least once a year and at this time the system must be reset. For vehicles without the CHANGE ENGINE OIL SOON message, An oil change is needed when the OIL LIFE REMAINING percentage is near 0%. Your dealer/retailer has trained service people who will perform this work using genuine parts and reset the system. It is also important to check the oil regularly and keep it at the proper level. If the system is ever reset accidentally, the oil must be changed at 5 000 km (3,000 miles) since the last oil change. Remember to reset the oil life system whenever the oil is changed. How to Reset the Engine Oil Life System The Engine Oil Life System calculates when to change the engine oil and filter based on vehicle use. Whenever the oil is changed, reset the system so it can calculate when the next oil change is required. If a situation occurs where the oil is changed prior to a CHANGE ENGINE OIL SOON message coming on, reset the system.

Always reset the engine oil life to 100% after every oil change. It will not reset itself. To reset the Engine Oil Life System on most vehicles:

1. Display the OIL LIFE REMAINING on the DIC.

If the vehicle does not have DIC buttons, the vehicle must be in P (Park) to access this display. See DIC Operation and Displays (With DIC Buttons) on page 4‑49 or DIC Operation and Displays (Without DIC Buttons) on page 4‑56.

2. Press and hold the SET/RESET button on the DIC,

or the trip odometer reset stem if the vehicle does not have DIC buttons, for more than five seconds. The oil life will change to 100%.

On all vehicles, the Engine Oil Life System can be reset as follows:

1. Turn the ignition to ON/RUN with the engine off 2. Fully press the accelerator pedal slowly three times

within five seconds.

3. Display the OIL LIFE REMAINING on the DIC. If the display shows 100%, the system is reset. See DIC Operation and Displays (With DIC Buttons) on page 4‑49 or DIC Operation and Displays (Without DIC Buttons) on page 4‑56.

If the vehicle has a CHANGE ENGINE OIL SOON message and it comes back on when the vehicle is started and/or the OIL LIFE REMAINING is near 0%, the Engine Oil Life System has not reset. Repeat the procedure. What to Do with Used Oil Used engine oil contains certain elements that can be unhealthy for your skin and could even cause cancer. Do not let used oil stay on your skin for very long. Clean your skin and nails with soap and water, or a good hand cleaner. Wash or properly dispose of clothing or rags containing used engine oil. See the manufacturer's warnings about the use and disposal of oil products. Used oil can be a threat to the environment. If you change your own oil, be sure to drain all the oil from the filter before disposal. Never dispose of oil by putting it in the trash, pouring it on the ground, into sewers, or into streams or bodies of water. Recycle it by taking it to a place that collects used oil. Engine Air Cleaner/Filter If the vehicle has a diesel engine, see “Pickup Models” under “Engine Air Cleaner/Filter” in the DURAMAX® Diesel Supplement for the correct inspection and replacement procedures. See Engine Compartment Overview on page 6‑16 for the location of the engine air cleaner/filter.

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Replacing the Engine Air Cleaner/Filter

1. Locate the air cleaner/filter assembly . See Engine

Compartment Overview on page 6‑16.

2. Loosen the four screws on the cover of the

housing and lift up the cover.

When to Inspect the Engine Air Cleaner/ Filter Inspect the air cleaner/filter at the Maintenance II intervals and replace it at the first oil change after each 50,000 mile (80 000 km) interval. See Scheduled Maintenance on page 7‑3 for more information. If driving on dusty/dirty conditions, inspect the filter at each engine oil change. How to Inspect the Engine Air Cleaner/ Filter To inspect the air cleaner/filter, remove the engine air cleaner/filter from the vehicle by following Steps 1 through 6. When the engine air cleaner/filter is removed, lightly shake it to release loose dust and dirt. If the engine air cleaner/filter remains caked with dirt, a new filter is required. Never use compressed air to clean the filter.

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{ WARNING:

Operating the engine with the air cleaner/filter off can cause you or others to be burned. The air cleaner not only cleans the air; it helps to stop flames if the engine backfires. Use caution when working on the engine and do not drive with the air cleaner/filter off.

Automatic Transmission Fluid (4-Speed Transmission) When to Check and Change Automatic Transmission Fluid A good time to check the automatic transmission fluid level is when the engine oil is changed. Change the fluid and filter at the intervals listed in Scheduled Maintenance on page 7‑3 and be sure to use the transmission fluid listed in Recommended Fluids and Lubricants on page 7‑13.

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3. Remove the engine air cleaner/filter from the

housing. Care should be taken to dislodge as little dirt as possible.

4. Clean the engine air cleaner/filter sealing surfaces

and the housing. Inspect or replace the engine air cleaner/filter.

5. 6. Reinstall the cover and tighten the screws.

How to Check Automatic Transmission Fluid Because this operation can be a little difficult, you may choose to have this done at the dealer/retailer service department. If you do it yourself, be sure to follow all the instructions here or you could get a false reading on the dipstick. Notice: Too much or too little fluid can damage your transmission. Too much can mean that some of the fluid could come out and fall on hot engine parts or exhaust system parts, starting a fire. Too little fluid could cause the transmission to overheat. Be sure to get an accurate reading if you check your transmission fluid. Wait at least 30 minutes before checking the transmission fluid level if you have been driving:

. When outside temperatures are above

32°C (90°F).

. At high speed for quite a while.

In heavy traffic — especially in hot weather.

. While pulling a trailer.

To get the right reading, the fluid should be at normal operating temperature, which is 82°C to 93°C (180°F to 200°F).

Get the vehicle warmed up by driving about 24 km (15 miles) when outside temperatures are above 10°C (50°F). If it is colder than 10°C (50°F), drive the vehicle in 3 (Third) until the engine temperature gage moves and then remains steady for 10 minutes. A cold fluid check can be made after the vehicle has been sitting for eight hours or more with the engine off, but this is used only as a reference. Let the engine run at idle for five minutes if outside temperatures are 10°C (50°F) or more. If it is colder than 10°C (50°F), you may have to idle the engine longer. Should the fluid level be low during this cold check, you must check the fluid hot before adding fluid. Checking the fluid hot will give you a more accurate reading of the fluid level. Checking the Fluid Level Prepare the vehicle as follows:

1. Park the vehicle on a level place. Keep the engine

running.

2. With the parking brake applied, place the shift

lever in P (Park).

3. With your foot on the brake pedal, move the shift lever through each gear range, pausing for about three seconds in each range. Then, position the shift lever in P (Park).

4. Let the engine run at idle for three minutes

or more.

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Then, without shutting off the engine, follow these steps:

1. Locate the

transmission dipstick handle with this graphic which is located at the rear of the engine compartment, on the passenger side of the vehicle.

See Engine Compartment Overview on page 6‑16
for more information on location.

2. Flip the handle up and then pull out the dipstick

and wipe it with a clean rag or paper towel.

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

then pull it back out again.

4. Check both sides of the dipstick, and read the

lower level. The fluid level must be in the COLD area, below the cross-hatched area, for a cold check or in the HOT or cross-hatched area for a hot check. Be sure to keep the dipstick pointed down to get an accurate reading. If the fluid level is in the acceptable range, push the dipstick back in all the way; then flip the handle down to lock the dipstick in place.

5.

Consistency of Readings Always check the fluid level at least twice using the procedure described previously. Consistency (repeatable readings) is important to maintaining proper fluid level. If readings are still inconsistent, contact your dealer/retailer.

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How to Add Automatic Transmission Fluid Refer to the Maintenance Schedule to determine what kind of transmission fluid to use. See Recommended Fluids and Lubricants on page 7‑13. Using a funnel, add fluid down the transmission dipstick tube only after checking the transmission fluid while it is hot. A cold check is used only as a reference. If the fluid level is low, add only enough of the proper fluid to bring the level up to the HOT area for a hot check. It does not take much fluid, generally less than 0.5 Liter (1 Pint). Do not overfill. Notice: Use of the incorrect automatic transmission fluid may damage the vehicle, and the damages may not be covered by the vehicle's warranty. Always use the automatic transmission fluid listed in Recommended Fluids and Lubricants on page 7‑13.

. After adding fluid, recheck the fluid level as described under “How to Check Automatic Transmission Fluid,” earlier in this section.

. When the correct fluid level is obtained, push the

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

Automatic Transmission Fluid (6-Speed Transmission) When to Check and Change Automatic Transmission Fluid It is usually not necessary to check the transmission fluid level. The only reason for fluid loss is a transmission leak or overheating the transmission. If you suspect a small leak, then use the following checking procedures to check the fluid level. However, if there is a large leak, then it may be necessary to have the vehicle towed to a dealer/retailer service department and have it repaired before driving the vehicle further. Notice: Use of the incorrect automatic transmission fluid may damage the vehicle, and the damages may not be covered by the vehicle's warranty. Always use the automatic transmission fluid listed in Recommended Fluids and Lubricants on page 7‑13. Change the fluid and filter at the intervals listed in the Maintenance Schedule. See Scheduled Maintenance on page 7‑3 . Be sure to use the transmission fluid listed in Recommended Fluids and Lubricants on page 7‑13 .

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How to Check Automatic Transmission Fluid Notice: Too much or too little fluid can damage your transmission. Too much can mean that some of the fluid could come out and fall on hot engine parts or exhaust system parts, starting a fire. Too little fluid could cause the transmission to overheat. Be sure to get an accurate reading if you check your transmission fluid. Before checking the fluid level, prepare the vehicle as follows:

1. Start the engine and park the vehicle on a level

surface. Keep the engine running.

2. Apply the parking brake and place the shift lever in

P (Park).

3. With your foot on the brake pedal, move the shift lever through each gear range, pausing for about three seconds in each range. Then, move the shift lever back to P (Park).

4. Allow the engine to idle (500 – 800 rpm) for at least

one minute. Slowly release the brake pedal.

5. Keep the engine running and press the Trip/Fuel

button or trip odometer reset stem until TRANS TEMP (Transmission Temperature) displays on the Driver Information Center (DIC).

6. Using the TRANS TEMP reading, determine and

perform the appropriate check procedure. If the TRANS TEMP reading is not within the required temperature ranges, allow the vehicle to cool, or operate the vehicle until the appropriate transmission fluid temperature is reached.

Cold Check Procedure Use this procedure only as a reference to determine if the transmission has enough fluid to be operated safely until a hot check procedure can be made. The hot check procedure is the most accurate method to check the fluid level. Perform the hot check procedure at the first opportunity. Use this cold check procedure to check fluid level when the transmission temperature is between 27°C and 32°C (80°F and 90°F).

1. Locate the

transmission dipstick at the rear of the engine compartment, on the passenger side of the vehicle.

See Engine Compartment Overview on page 6‑16
for more information.

2. Flip the handle up, and then pull out the dipstick

and wipe it with a clean rag or paper towel.

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3.

Install the dipstick by pushing it back in all the way, wait three seconds, and then pull it back out again. 4. Check both sides of the dipstick and read the lower

level. Repeat the check procedure to verify the reading.

5.

If the fluid level is below the COLD check band, add only enough fluid as necessary to bring the level into the COLD band. It does not take much fluid, generally less than 0.5 Liter (1 Pint). Do not overfill.

6. Perform a hot check at the first opportunity

after the transmission reaches a normal operating temperature between 71°C to 93°C (160°F to 200°F).

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7.

If the fluid level is in the acceptable range, push the dipstick back in all the way, then flip the handle down to lock the dipstick in place.

Hot Check Procedure Use this procedure to check the transmission fluid level when the transmission fluid temperature is between 71°C and 93°C (160°F and 200°F). The hot check is the most accurate method to check the fluid level. The hot check should be performed at the first opportunity in order to verify the cold check. The fluid level rises as fluid temperature increases, so it is important to ensure the transmission temperature is within range.

1. Locate the

transmission dipstick at the rear of the engine compartment, on the passenger side of the vehicle.

See Engine Compartment Overview on page 6‑16
for more information.

2. Flip the handle up, and then pull out the dipstick

3.

and wipe it with a clean rag or paper towel. Install the dipstick by pushing it back in all the way, wait three seconds, and then pull it back out again. 4. Check both sides of the dipstick and read the lower

level. Repeat the check procedure to verify the reading.

or drain fluid as necessary to bring the level into the HOT band. If the fluid level is low, add only enough fluid to bring the level into the HOT band. It does not take much fluid, generally less than 0.5 Liter (1 Pint). Do not overfill. If the fluid level is in the acceptable range, push the dipstick back in all the way, then flip the handle down to lock the dipstick in place.

6.

Consistency of Readings Always check the fluid level at least twice using the procedure described previously. Consistency (repeatable readings) is important to maintaining proper fluid level. If readings are still inconsistent, contact your dealer/retailer.

5. Safe operating level is within the HOT cross hatch band on the dipstick. If the fluid level is not within the HOT band, and the transmission temperature is between 71°C and 93°C (160°F and 200°F), add

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{ WARNING:

An electric engine cooling fan can start even when the engine is not running. To avoid injury, always keep hands, clothing, and tools away from any engine cooling fan.

{ WARNING:

Heater and radiator hoses, and other engine parts, can be very hot. Do not touch them. If you do, you can be burned. Do not run the engine if there is a leak. If you run the engine, it could lose all coolant. That could cause an engine fire, and you could be burned. Get any leak fixed before you drive the vehicle.

Cooling System If your vehicle has the DURAMAX® Diesel engine, see the DURAMAX® Diesel manual for more information. The Cooling System allows the engine to maintain the correct working temperature.

5.3 L V8 Engine (4.3 L V6 Engine, 4.8 L V6 Engine,

6.0 L V8 engine and 6.2 L V8 Engine similar)

A. Coolant Surge Tank B. Coolant Surge Tank Pressure Cap C. Engine Cooling Fan

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Notice: Using coolant other than DEX-COOL® can cause premature engine, heater core, or radiator corrosion. In addition, the engine coolant could require changing sooner, at 50 000 km (30,000 miles) or 24 months, whichever occurs first. Any repairs would not be covered by the vehicle warranty. Always use DEX-COOL® (silicate-free) coolant in the vehicle. Engine Coolant The cooling system in the vehicle is filled with DEX-COOL® engine coolant. This coolant is designed to remain in the vehicle for five years or 150,000 miles (240 000 km), whichever occurs first. The following explains the cooling system and how to check and add coolant when it is low. If there is a problem with engine overheating, see Engine Overheating on page 6‑34.

What to Use

{ WARNING:

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

Use a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant. If using this mixture, nothing else needs to be added. This mixture:

. Gives freezing protection down to −34°F (−37°C),

outside temperature.

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

engine temperature.

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. Protects against rust and corrosion. . Will not damage aluminum parts. . Helps keep the proper engine temperature.

Notice: If an improper coolant mixture is used, the engine could overheat and be badly damaged. The repair cost would not be covered by the vehicle warranty. Too much water in the mixture can freeze and crack the engine, radiator, heater core, and other parts. Notice: If extra inhibitors and/or additives are used in the vehicle's cooling system, the vehicle could be damaged. Use only the proper mixture of the engine coolant listed in this manual for the cooling system. See Recommended Fluids and Lubricants on page 7‑13 for more information. Checking Coolant The coolant surge tank is located in the engine compartment on the passenger side of the vehicle. See Engine Compartment Overview on page 6‑16 for more information on location. The vehicle must be on a level surface when checking the coolant level. Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down. If coolant is visible but the coolant level is not at or

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above the FULL COLD mark, add a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant at the coolant surge tank, but be sure the cooling system is cool before this is done.

The coolant level should be at or above the FULL COLD mark. If it is not, you may have a leak in the cooling system. If the vehicle has a low coolant sensor and the LOW COOLANT LEVEL message comes on and stays on, it means you are low on engine coolant. See “LOW COOLANT LEVEL” under DIC Warnings and Messages on page 4‑63 .

How to Add Coolant to the Coolant Surge Tank for Gasoline Engines If the vehicle has a diesel engine, see “Cooling System” in the DURAMAX® Diesel Supplement for the proper coolant fill procedure.

{ WARNING:

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

Notice: This vehicle has a specific coolant fill procedure. Failure to follow this procedure could cause the engine to overheat and be severely damaged.

{ WARNING:

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

{ WARNING:

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

If no coolant is visible in the surge tank, add coolant as follows:

1. Remove the coolant surge tank pressure cap when the cooling system, including the coolant surge tank pressure cap and upper radiator hose, is no longer hot.

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Turn the pressure cap slowly counterclockwise about one full turn. If you hear a hiss, wait for that to stop. A hiss means there is still some pressure left.

By this time, the coolant level inside the coolant surge tank may be lower. If the level is lower, add more of the proper mixture to the coolant surge tank until the level reaches the FULL COLD mark.

2. Keep turning the pressure cap slowly, and

5. Replace the pressure cap. Be sure the pressure

remove it.

3. Fill the coolant surge tank with the proper mixture

to the FULL COLD mark.

4. With the coolant surge tank pressure cap off, start

the engine and let it run until the engine coolant temperature gage indicates approximately 195°F (90°C).

6-34

cap is hand-tight and fully seated.

6. Verify coolant level after engine is shut off and the

coolant is cold. If necessary, repeat coolant fill procedure Steps 1 through 6.

Notice: If the pressure cap is not tightly installed, coolant loss and possible engine damage may occur. Be sure the cap is properly and tightly secured. Engine Overheating If the vehicle has the DURAMAX® Diesel engine, see the DURAMAX® Diesel manual for more information. The vehicle has several indicators to warn of engine overheating. You will find a coolant temperature gage on the vehicle's instrument panel. See Engine Coolant Temperature Gage on page 4‑40. In addition, you will find ENGINE OVERHEATED STOP ENGINE, ENGINE OVERHEATED IDLE ENGINE, and ENGINE POWER IS REDUCED messages in the Driver Information Center (DIC) on the instrument panel. See DIC Warnings and Messages on page 4‑63.

You may decide not to lift the hood when this warning appears, but instead get service help right away. See Roadside Assistance Program on page 8‑7. If you do decide to lift the hood , make sure the vehicle is parked on a level surface. Then check to see if the engine cooling fans are running. If the engine is overheating, both fans should be running. If they are not, do not continue to run the engine and have the vehicle serviced. Notice: Engine damage from running your engine without coolant is not covered by your warranty. See Overheated Engine Protection Operating Mode on page 6‑36 for information on driving to a safe place in an emergency. Notice: If the engine catches fire while driving with no coolant, the vehicle can be badly damaged. The costly repairs would not be covered by the vehicle warranty. See Overheated Engine Protection Operating Mode on page 6‑36 for information on driving to a safe place in an emergency.

If Steam Is Coming From The Engine Compartment

{ WARNING:

Steam from an overheated engine can burn you badly, even if you just open the hood. Stay away from the engine if you see or hear steam coming from it. Turn it off and get everyone away from the vehicle until it cools down. Wait until there is no sign of steam or coolant before you open the hood. If you keep driving when the vehicles engine is overheated, the liquids in it can catch fire. You or others could be badly burned. Stop the engine if it overheats, and get out of the vehicle until the engine is cool. See Overheated Engine Protection Operating Mode on page 6‑36 for information on driving to a safe place in an emergency.

6-35

If No Steam Is Coming From The Engine Compartment The ENGINE OVERHEATED STOP ENGINE or the ENGINE OVERHEATED IDLE ENGINE message, along with a low coolant condition, can indicate a serious problem. If you get an engine overheat warning, but see or hear no steam, the problem may not be too serious. Sometimes the engine can get a little too hot when you:

. Climb a long hill on a hot day. . Stop after high-speed driving. Idle for long periods in traffic. Tow a trailer. See Towing a Trailer on page 5‑49. If you get the ENGINE OVERHEATED STOP ENGINE or the ENGINE OVERHEATED IDLE ENGINE message with no sign of steam, try this for a minute or so:

1. Turn the air conditioning off. 2. Turn the heater on to the highest temperature and

3.

to the highest fan speed. Open the windows as necessary. If you are stopped in a traffic jam, apply the brake, shift to N (Neutral); otherwise, shift to the highest gear while driving — D (Drive) or 3 (Third).

6-36

If the temperature overheat gage is no longer in the overheat zone or an overheat warning no longer displays, the vehicle can be driven. Continue to drive the vehicle slow for about 10 minutes. Keep a safe vehicle distance from the car in front of you. If the warning does not come back on, continue to drive normally. If the warning continues, pull over, stop, and park the vehicle right away. If there is no sign of steam, idle the engine for five minutes while parked. If the warning is still displayed, turn off the engine until it cools down. Also, see “Overheated Engine Protection Operating Mode” later in this section. Overheated Engine Protection Operating Mode If an overheated engine condition exists and the REDUCED ENGINE POWER message is displayed, an overheat protection mode which alternates firing groups of cylinders helps prevent engine damage. In this mode, you will notice a loss in power and engine performance. This operating mode allows the vehicle to be driven to a safe place in an emergency. Driving extended miles (km) and/or towing a trailer in the overheat protection mode should be avoided.

Notice: After driving in the overheated engine protection operating mode, to avoid engine damage, allow the engine to cool before attempting any repair. The engine oil will be severely degraded. Repair the cause of coolant loss, change the oil and reset the oil life system. See Engine Oil on page 6‑18. Engine Fan Noise If the vehicle has a clutched engine cooling fan, when the clutch is engaged, the fan spins faster to provide more air to cool the engine. In most everyday driving conditions, the fan is spinning slower and the clutch is not fully engaged. This improves fuel economy and reduces fan noise. Under heavy vehicle loading, trailer towing, and/or high outside temperatures, the fan speed increases as the clutch more fully engages, so you may hear an increase in fan noise. This is normal and should not be mistaken as the transmission slipping or making extra shifts. It is merely the cooling system functioning properly. The fan will slow down when additional cooling is not required and the clutch disengages. You may also hear this fan noise when you start the engine. It will go away as the fan clutch partially disengages. If the vehicle has electric cooling fans, you may hear the fans spinning at low speed during most everyday driving. The fans may turn off if no cooling is required.

Under heavy vehicle loading, trailer towing, and/or high outside temperatures, or if you are operating the air conditioning system, the fans may change to high speed and you may hear an increase in fan noise. This is normal and indicates that the cooling system is functioning properly. The fans will change to low speed when additional cooling is no longer required. Power Steering Fluid

See Engine Compartment Overview on page 6‑16
for reservoir location.

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

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How to Check Power Steering Fluid To check the power steering fluid:

1. Turn the key off and let the engine compartment

cool down.

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

clean rag.

4. Replace the cap and completely tighten it. 5. Remove the cap again and look at the fluid level

on the dipstick.

The level should be at the FULL COLD mark. If necessary, add only enough fluid to bring the level up to the mark. What to Use To determine what kind of fluid to use, see Recommended Fluids and Lubricants on page 7‑13 . Always use the proper fluid. Notice: Use of the incorrect fluid may damage the vehicle and the damages may not be covered by the vehicle's warranty. Always use the correct fluid listed in Recommended Fluids and Lubricants on page 7‑13.

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Windshield Washer Fluid What to Use When windshield washer fluid needs to be added, be sure to read the manufacturer's instructions before use. Use a fluid that has sufficient protection against freezing in an area where the temperature may fall below freezing. Adding Washer Fluid The vehicle has a low washer fluid message in the DIC that comes on when the washer fluid is low. The message is displayed for 15 seconds at the start of each ignition cycle. When the WASHER FLUID LOW ADD FLUID message displays, 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 6‑16 for reservoir location.

Notice:

. When using concentrated washer fluid,

follow the manufacturer's instructions for adding water.

. Do not mix water with ready-to-use washer

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

. Do not use engine coolant (antifreeze) in the windshield washer. It can damage the vehicle's windshield washer system and paint.

Brakes Brake Fluid

The brake master cylinder reservoir is filled with DOT 3 brake fluid. See Engine Compartment Overview on page 6‑16
for the location of the reservoir.

There are only two reasons why the brake fluid level in the reservoir might go down:

The brake fluid level goes down because of normal brake lining wear. When new linings are installed, the fluid level goes back up.

. A fluid leak in the brake hydraulic system can also

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

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

{ WARNING:

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

Refer to the Maintenance Schedule to determine when to check the brake fluid. See Scheduled Maintenance on page 7‑3 . Checking Brake Fluid Check brake fluid by looking at the brake fluid reservoir. See Engine Compartment Overview on page 6‑16.

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

After work is done on the brake hydraulic system, make sure the level is above the MIN but not over the MAX mark. What to Add Use only new DOT 3 brake fluid from a sealed container. See Recommended Fluids and Lubricants on page 7‑13 . Always clean the brake fluid reservoir cap and the area around the cap before removing it. This helps keep dirt from entering the reservoir.

{ WARNING:

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

Notice:

. Using the wrong fluid can badly damage

brake hydraulic system parts. For example, just a few drops of mineral-based oil, such as engine oil, in the brake hydraulic system can damage brake hydraulic system parts so badly that they will have to be replaced. Do not let someone put in the wrong kind of fluid. If brake fluid is spilled on the vehicle's painted surfaces, the paint finish can be damaged. Be careful not to spill brake fluid on the vehicle. If you do, wash it off immediately. See Washing Your Vehicle on page 6‑113.

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

{ WARNING:

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

Notice: Continuing to drive with worn-out brake pads could result in costly brake repair. Some driving conditions or climates can cause a brake squeal when the brakes are first applied or lightly applied. This does not mean something is wrong with the brakes.

6-41

Properly torqued wheel nuts are necessary to help prevent brake pulsation. When tires are rotated, inspect brake pads for wear and evenly tighten wheel nuts in the proper sequence to torque specifications in Capacities and Specifications on page 6‑126. If the vehicle has rear drum brakes, they do not have wear indicators, but if a rear brake rubbing noise is heard, have the rear brake linings inspected immediately. Rear brake drums should be removed and inspected each time the tires are removed for rotation or changing. Drum brakes have an inspection hole to inspect lining wear during scheduled maintenance. When the front brake pads are replaced, have the rear brakes inspected, too. Brake linings should always be replaced as complete axle sets. Brake Pedal Travel See your dealer/retailer if the brake pedal does not return to normal height, or if there is a rapid increase in pedal travel. This could be a sign that brake service might be required.

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

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Battery If the vehicle is a Two‐mode Hybrid, see the Two‐mode Hybrid manual for more information. This vehicle has a maintenance free battery (or batteries). Refer to the replacement number on the original battery label when a new battery is needed. See Engine Compartment Overview on page 6‑16 for battery location.

{ DANGER:

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

Vehicle Storage

{ WARNING:

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

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

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Jump Starting If the vehicle is a Two-mode Hybrid, see the Two-mode Hybrid manual for more information. If the 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.

{ WARNING:

Batteries can hurt you. They can be dangerous because:

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

Notice: Ignoring these steps could result in costly damage to the vehicle that would not be covered by the warranty. Trying to start the vehicle by pushing or pulling it will not work, and it could damage the vehicle.

1. Check the other vehicle. It must have a 12-volt

battery with a negative ground system.

Notice: If the other vehicle's system is not a 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.

If you have a vehicle with a diesel engine with two batteries, you should know before you begin that, especially in cold weather, you may not be able to get enough power from a single battery in another vehicle to start your diesel engine. If your vehicle has more than one battery, using the battery that is closer to the starter will reduce electrical resistance. This is located on the passenger side, in the rear of the engine compartment.

3. 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 an unwanted ground connection. You would not be able to start your vehicle, and the bad grounding could damage the electrical systems.

6-44

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 P (Park) 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.

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

4. 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!

5. Open the hood on the other vehicle and locate the positive (+) and negative (−) terminal locations on that vehicle. The positive (+) terminal, is located under a red plastic cover at the positive battery post. To uncover the positive (+) terminal, open the red plastic cover.

The remote negative (−) terminal is a stud located on the right front passenger side of the engine, where the negative battery cable attaches. See Engine Compartment Overview on page 6‑16.

6-45

{ WARNING:

WARNING: (Continued)

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.

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.

{ WARNING:

{ WARNING:

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

Using an open flame near a battery can cause battery gas to explode. People have been hurt doing this, and some have been blinded. Use a flashlight if you need more light. Be sure the battery has enough water. You do not need to add water to the battery installed in your new vehicle. But if a battery has filler caps, be sure the right amount of fluid is there. If it is low, add water to take care of that first. If you do not, explosive gas could be present.

(Continued)

6-46

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

7. Connect the red

positive (+) cable to the positive (+) terminal of the vehicle with the dead battery.

8. 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.

9. 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.

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

a heavy, unpainted metal engine part or to the remote negative (−) terminal, on the vehicle with the dead battery.

11. Start the vehicle with the good battery and run the

engine for a while.

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

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

5.3L engine (4.3L, 4.8L, 6.0L and 6.2L similar)

6-47

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 the vehicle warranty. Always connect and remove the jumper cables in the correct order, making sure that the cables do not touch each other or other metal.

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

6-48

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 positive (+) terminal cover, to its original

position.

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. How to Check Lubricant

All Other Series and Engines

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

For all 4.3L, 4.8L and 5.3L 1500 Series applications, the proper level is 0.04 inches to 0.75 inches (1.0 mm to 19.0 mm) below the bottom of the filler hole, located on the rear axle. Add only enough fluid to reach the proper level. For all 6.0L and 6.2L 1500 Series applications, the proper level is from 0.6 inches 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.

6-49

2500HD with 6.0L and 6.2L

How to Check Lubricant

Electric Shift Transfer Case

A. Fill Plug B. Drain Plug

For all 6.0L and 6.2L 2500HD Series applications, the proper level is from 0 to 0.5 inches (0 mm to 13 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level. For all 6.6L DURAMAX DIESEL 2500HD Series applications and all 3500 Series applications, the proper level is from 0.6 inches to 0.8 inches (17 mm to 21 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 7‑13. Four-Wheel Drive Lubricant checks in this section also apply to these vehicles. 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.

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Manual Shift Transfer Case

Active Transfer Case

A. Fill Plug B. Drain Plug

A. Fill Plug B. Drain Plug

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, located on the transfer case, 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.

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When to Change Lubricant Refer to the Maintenance Schedule to determine how often to change the lubricant. See Scheduled Maintenance on page 7‑3. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 7‑13. 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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1500 Series

A : Fill Plug B : Drain Plug

What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 7‑13. Noise Control System

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

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All except 1500 Series

A : Fill Plug B : Drain Plug

. 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.

. When the differential is at operating temperature (warm), add enough lubricant to raise the level to the bottom of the filler plug hole.

Federal law prohibits the following acts or the causing thereof:

1. The removal or rendering inoperative by any

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

2. The use of the vehicle after such device or element

of design has been removed or rendered inoperative by any person.

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

insulation.

Engine: . Removal or rendering engine speed governor,

if the vehicle has one, inoperative so as to allow engine speed to exceed manufacturer specifications. Fan and Drive: . Removal of fan clutch, if the vehicle has one,

or rendering clutch inoperative.

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

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

clamps.

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 a crash, the aim of the headlamps can be affected and adjustment can be necessary. If oncoming vehicles flash their high beams at you, this can 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.

The vehicle should:

To adjust the vertical aim:

. Be placed so the headlamps are 25 ft. (7.6 m) from

1. Open the hood. See Hood Release on page 6‑15

a light colored wall.

for more information.

. Have all four tires on a level surface which is level

all the way to the wall.

. Be placed so it is perpendicular to the wall. . Not have any snow, ice, or mud on it. . Be fully assembled and all other work stopped

while headlamp aiming is being performed.

. Be normally loaded with a full tank of fuel and one person or 160 lbs (75 kg) sitting on the driver seat.

. Have tires properly inflated. . Have 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.

2. Locate the aim dot on the lens of the low‐beam

headlamp.

3. Record the distance from the ground to the aim dot

on the low‐beam headlamp.

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4. At a wall 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.

6-56

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.

Halogen Bulbs

{ WARNING:

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

Headlamps To replace one of these bulbs:

1. Open the hood. See Hood Release on page 6‑15

2.

for more information. If you are replacing the bulb on the passenger side remove the Engine Air Cleaner cover. See Engine Air Cleaner/Filter on page 6‑21 for more information.

3. Reach in and access the bulb sockets from inside

the engine compartment.

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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.

Bulb Replacement For the proper type of replacement bulbs, see Replacement Bulbs on page 6‑62. For any bulb changing procedure not listed in this section, contact your dealer/retailer.

8. Reinstall the new bulb socket into the headlamp

assembly and turn it clockwise to secure.

9. Close the hood. Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp To replace one of these bulbs:

1. Remove the screws and lift off the lamp assembly.

4. Turn the bulb socket counterclockwise to remove

it from the headlamp assembly and pull it straight out.

5. Unplug the electrical connector from the old bulb

by releasing the clips on the bulb socket.

6. Replace it with a new bulb socket. 7. Plug in the electrical connector to the new bulb

socket.

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A. Cargo Lamp B. Center High-Mounted Stoplamp Bulb (CHMSL)

2. Remove the bulbs by turning socket

3.

counterclockwise and pulling the bulb straight out. Install the bulbs by pushing the bulb straight in and turning clockwise.

4. Reinstall the lamp assembly and tighten the

screws.

Pickup Box Identification and Fender Marker Lamps To replace a pickup box identification or fender marker lamp bulb:

1. Press the tab from the back to remove the lamp. 2. Unplug the lamp assembly harness. 3. Gently pry the individual lamp from the lamp

assembly.

4. Unplug the lamp. 5. Plug in a new lamp and snap it into the assembly. 6. Reinstall the lamp assembly.

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Taillamps, Turn Signal, Stoplamps and Back-up Lamps To replace one of these bulbs:

1. Open the tailgate. Tailgate on page 3‑12 for more

information.

2. Remove the two rear

lamp assembly screws near the tailgate latch strikerpost and pull out the lamp assembly.

3. Determine which of the following taillamp

assemblies applies to your vehicle.

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Dual Tire Models

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

4. Press the tab, if the vehicle has one, and turn the

bulb socket counterclockwise to remove it from the taillamp assembly.

Taillamps (Chassis Cab Models)

All Other Models

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

5. Pull the old bulb straight out from the socket. 6. Press a new bulb into the socket and turn the

socket clockwise into the taillamp assembly.

7. Reinstall the taillamp assembly.

A. Backup Lamp B. Stoplamp/Taillamp/Turn

Signal Lamp

To replace one of these bulbs: 1. Remove the four screws. 2. Lift the lens off the lamp assembly. 3. Turn the old bulb counterclockwise and pull the it

straight out from the socket.

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Replacement Bulbs

Exterior Lamp

Back-up Lamp Back-up Lamp* Cargo Lamp and Center High-Mounted Stoplamp (CHMSL) Fender Marker Lamp High-Beam Headlamp Low-Beam Headlamp License Plate Lamp Sidemarker Lamp/Stoplamp/Taillamp/ Turn Signal Lamp Stoplamp/Turn Signal Lamp/Taillamp* * Chassis Cab Models

Bulb Number 3047 or 921

1156

912

W5WLL

9005
H11
168

3047

1157

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

4.

Install a new bulb into the socket, turn it clockwise, and press it in until it is tight.

5. Reinstall the lens and the four screws. License Plate Lamp To replace one of these bulbs:

1. Reach under the rear bumper for the bulb socket.

2. Turn the bulb socket counterclockwise and pull the

bulb socket out of the connector.

3. Pull the old bulb from the bulb socket, keeping the

bulb straight as you pull it out. Install the new bulb.

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

socket.

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Windshield Wiper Blade Replacement Windshield wiper blades should be inspected for wear or cracking. See Scheduled Maintenance on page 7‑3
for more information on wiper blade inspection. Replacement blades come in different types and are removed in different ways. Here is how to remove the wiper blade:

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 Maintenance Replacement Parts on page 7‑15.

2. Squeeze the grooved areas on each side of the

blade and turn the blade assembly away from the arm connector.

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

{ CAUTION:

Poorly maintained and improperly used tires are dangerous. . Overloading your vehicle's tires can cause overheating as a result of too much flexing. You could have an air-out and a serious accident. See Loading the Vehicle on page 5‑29.

. 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.

(Continued)

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CAUTION: (Continued)

Tire pressure should be checked when your vehicle's tires are cold. See Inflation - Tire Pressure on page 6‑72. . Overinflated tires are more likely to be cut, punctured, or broken by a sudden impact — such as when you hit a pothole. Keep tires at the recommended pressure.

. Worn, old tires can cause accidents.

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

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 or commercial uses such as snow plowing. See Off-Road Driving on page 5‑11 and Adding a Snow Plow or Similar Equipment on page 5‑36 for additional information.

Notice: If the vehicle has low‐profile tires, they are more susceptible to damage from road hazards or curb impact than standard profile tires. Tire and/or wheel assembly damage can occur when coming into contact with road hazards like, potholes, or sharp edged objects, or when sliding into a curb. The vehicle warranty does not cover this type of damage. Keep tires set to the correct inflation pressure and, when possible avoid contact with curbs, potholes, and other road hazards.

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

Passenger (P‐Metric) Tire

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

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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) DOT (Department of Transportation) : The Department of Transportation (DOT) code indicates that the tire is in compliance with the U.S. Department of Transportation Motor Vehicle Safety Standards. (D) Tire Identification Number (TIN) : The letters and numbers following DOT code are the Tire Identification Number (TIN). The TIN shows the manufacturer and plant code, tire size, and date the tire was manufactured. The TIN is molded onto both sides of the tire, although only one side may have the date of manufacture.

(E) Tire Ply Material : The type of cord and number of plies in the sidewall and under the tread. (F) Uniform Tire Quality Grading (UTQG) : Tire manufacturers are required to grade tires based on three performance factors: treadwear, traction, and temperature resistance. For more information, see Uniform Tire Quality Grading on page 6‑85. (G) Maximum Cold Inflation Load Limit : Maximum load that can be carried and the maximum pressure needed to support that load. For information on recommended tire pressure see Inflation - Tire Pressure on page 6‑72 and Loading the Vehicle on page 5‑29.

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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 6‑72 and Loading the Vehicle on page 5‑29. (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.

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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.

(F) Tire Ply Material : The type of cord and number of plies in the sidewall and under the tread. (G) Single Tire Maximum Load : Maximum load that can be carried and the maximum pressure needed to support that load when used as a single. For information on recommended tire pressure see Inflation - Tire Pressure on page 6‑72
and Loading the Vehicle on page 5‑29. Tire Size The following examples show the different parts of a tire size.

Passenger (P‐Metric) Tire

(A) Passenger (P‐Metric) Tire : The United States version of a metric tire sizing system. The letter P as the first character in the tire size means