2011 GMC Sierra Owners Manual

10. Release the parking brake prior

to moving the vehicle.

11. Turn the ignition to LOCK/OFF.

Shifting Out of Neutral To shift the transfer case out of N (Neutral) do the following: 1. Set the parking brake and apply

the regular brake pedal.

2. Turn the ignition to ON/RUN with the engine off, and shift the transmission to N (Neutral).

3. Turn the transfer case dial to

Two-Wheel Drive High. After the transfer case has shifted out of N (Neutral), the N (Neutral) light will go out.

4. Release the parking brake prior

to moving the vehicle.

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Notice: Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case. To help avoid damaging the vehicle, always wait for the mode indicator lights to stop flashing before shifting the transmission into gear. 5. Start the engine and shift the

transmission to the desired position.

Excessively shifting the transfer case into or out of the different modes may cause the transfer case to enter the shift protection mode. This will protect the transfer case from possible damage and will only allow the transfer case to respond to one shift per 10 seconds. The transfer case may stay in this mode for up to three minutes.

Automatic Transfer Case

The transfer case knob is located next to the steering column. Use the dial to shift into and out of Four-Wheel Drive.

Driving and Operating

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You can choose among five driving settings: Indicator lights in the dial show which setting you are in. The indicator lights will come on briefly when you turn on the ignition and one will stay on. If the lights do not come on, you should take the vehicle to your dealer for service. An indicator light will flash while shifting the transfer case. It will remain illuminated when the shift is complete. If for some reason the transfer case cannot make a requested shift, it will return to the last chosen setting. 2 m (Two-Wheel Drive High): This setting is used for driving in most street and highway situations. The front axle is not engaged in Two-Wheel Drive. This setting also provides the best fuel economy.

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Driving and Operating

AUTO (Automatic Four-Wheel Drive): This setting is ideal for use when road surface traction conditions are variable. When driving the vehicle in AUTO, the front axle is engaged, but the vehicle's power is sent only to the front and rear wheels automatically based on driving conditions. Driving in this mode results in slightly lower fuel economy than Two-Wheel Drive High. 4 m (Four-Wheel Drive High): Use the Four-Wheel Drive High position when extra traction is needed, such as on snowy or icy roads or in most off-road situations. This setting also engages the front axle to help drive the vehicle. This is the best setting to use when plowing snow.

4 n (Four-Wheel Drive Low): This setting also engages the front axle and delivers extra torque. You may never need this setting. It sends maximum power to all four wheels. You might choose Four-Wheel Drive Low if you are driving off-road in deep sand, deep mud, deep snow, and while climbing or descending steep hills. If the vehicle has StabiliTrak®, shifting into Four-Wheel Drive Low will turn Traction Control and StabiliTrak off. See StabiliTrak® System on page 9‑70.

{ WARNING

Shifting the transfer case to N (Neutral) can cause the vehicle to roll even if the transmission is in P (Park). You or someone else could be seriously injured. Be sure to set the parking brake before placing the transfer case in N (Neutral). See Parking Brake on page 9‑69.

N (Neutral): Shift the vehicle's transfer case to N (Neutral) only when towing the vehicle. See Recreational Vehicle Towing on page 10‑103 or Towing the Vehicle on page 10‑103 for more information. If the SERVICE 4 WHEEL DRIVE message stays on, you should take the vehicle to your dealer for service. See “SERVICE 4 WHEEL DRIVE message” under Transmission Messages on page 5‑50.

Shifting Into Four-Wheel Drive High or AUTO (Automatic Four-Wheel Drive) Turn the knob to the Four-Wheel Drive High or AUTO position. This can be done at any speed, except when shifting from Four-Wheel Drive Low. The indicator light will flash while shifting. It will remain on when the shift is completed.

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Shifting Into Two-Wheel Drive High Turn the knob to the Two-Wheel Drive High position. This can be done at any speed, except when shifting from Four-Wheel Drive Low. The indicator light will flash while shifting. It will remain on when the shift is completed.

Shifting Into Four-Wheel Drive Low When Four-Wheel Drive Low is engaged, vehicle speed should be kept below 72 km/h (45 mph). Extended high-speed operation in Four-Wheel Drive Low may damage or shorten the life of the drivetrain.

To shift to the Four-Wheel Drive Low position, the ignition must be in ON/RUN and the vehicle must be stopped or moving less than 5 km/h (3 mph) with the transmission in N (Neutral). The preferred method for shifting into Four-Wheel Drive Low is to have the vehicle moving 1.6 to 3.2 km/h (1 to 2 mph). Turn the knob to the Four-Wheel Drive Low position. You must wait for the Four-Wheel Drive Low indicator light to stop flashing and remain on before shifting the transmission into gear. Notice: Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case. To help avoid damaging the vehicle, always wait for the mode indicator lights to stop flashing before shifting the transmission into gear.

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It is typical for the vehicle to exhibit significant engagement noise and bump when shifting between Four-Wheel Drive Low and Four-Wheel Drive High ranges or from N (Neutral) with the engine running. If the knob is turned to the Four-Wheel Drive Low position when the vehicle is in gear and/or moving, the Four-Wheel Drive Low indicator light will flash for 30 seconds and not complete the shift unless the vehicle is moving less than 5 km/h (3 mph) and the transmission is in N (Neutral). After 30 seconds the transfer case will shift to Four-Wheel Drive High mode.

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Driving and Operating

Shifting Out of Four-Wheel Drive Low To shift from Four-Wheel Drive Low to Four-Wheel Drive High, AUTO or Two-Wheel Drive High, the vehicle must be stopped or moving less than 5 km/h (3 mph) with the transmission in N (Neutral) and the ignition in ON/RUN. The preferred method for shifting out of Four-Wheel Drive Low is to have the vehicle moving 1.6 to 3.2 km/h (1 to 2 mph). Turn the knob to the Four-Wheel Drive High, AUTO or Two-Wheel Drive High position. You must wait for the Four-Wheel Drive High, AUTO or Two-Wheel Drive High indicator light to stop flashing and remain on before shifting the transmission into gear. Notice: Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the

transfer case. To help avoid damaging the vehicle, always wait for the mode indicator lights to stop flashing before shifting the transmission into gear. It is typical for the vehicle to exhibit significant engagement noise and bump when shifting between Four-Wheel Drive Low and Four-Wheel Drive High ranges or from N (Neutral) with the engine running. If the knob is turned to the Four-Wheel Drive High, AUTO, or Two-Wheel Drive High switch position when the vehicle is in gear and/or moving, the Four-Wheel Drive High, AUTO or Two-Wheel Drive High indicator light will flash for 30 seconds but will not complete the shift unless the vehicle is moving less than 5 km/h (3 mph) and the transmission is in N (Neutral).

Shifting into Neutral To shift the transfer case to N (Neutral) do the following: 1. Make sure the vehicle is parked

so that it will not roll.

2. Set the parking brake and

apply the regular brake pedal. See Parking Brake on page 9‑69
for more information.

3. Shifting the transfer case into N (Neutral) can be done with or without the engine running. Shifting without the engine running should be done with the ignition in ON/RUN. 4. Put the transmission in

N (Neutral).

5. Shift the transfer case to

Two-Wheel Drive High.

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Driving and Operating

9-67

6. Turn the transfer case dial

10. Release the parking brake prior

4. Release the parking brake prior

clockwise to N (Neutral) until it stops and hold it there until the N (Neutral) light starts blinking. This will take at least 10 seconds. Then slowly release the dial to the four low position. The N (Neutral) light will come on when the transfer case shift to N (Neutral) is complete. If the engine is running, make sure that the transfer case is in N (Neutral) by shifting the transmission to R (Reverse) for one second, then shift the transmission to D (Drive) for one second.

7.

8. Turn the ignition to

ACC/ACCESSORY, which will turn the engine off.

9. Place the transmission shift

lever in P (Park).

to moving the vehicle.

to moving the vehicle.

Notice: Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case. To help avoid damaging the vehicle, always wait for the mode indicator lights to stop flashing before shifting the transmission into gear. 5. Start the engine and shift the

transmission to the desired position.

11. Turn the ignition to LOCK/OFF.

Shifting Out of Neutral To shift out of N (Neutral) do the following: 1. Set the parking brake and apply

the regular brake pedal.

2. Turn the ignition to ON/RUN with

the engine off, and shift the transmission to N (Neutral). 3. Turn the transfer case dial to Two-Wheel Drive High, Four-Wheel Drive High, or AUTO. After the transfer case has shifted out of N (Neutral), the N (Neutral) light will go out.

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Driving and Operating

Brakes

Antilock Brake System (ABS) This vehicle has the Antilock Brake System (ABS), an advanced electronic braking system that helps prevent a braking skid. When the engine is started and the vehicle begins to drive away, ABS checks itself. A momentary motor or clicking noise might be heard while this test is going on, and it might even be noticed that the brake pedal moves a little. This is normal.

As the brakes are applied, the computer keeps receiving updates on wheel speed and controls braking pressure accordingly. Remember: ABS does not change the time needed to get a foot up to the brake pedal or always decrease stopping distance. If you get too close to the vehicle in front of you, there will not be enough time to apply the brakes if that vehicle suddenly slows or stops. Always leave enough room up ahead to stop, even with ABS. Using ABS Do not pump the brakes. Just hold the brake pedal down firmly and let ABS work. You might hear the ABS pump or motor operating and feel the brake pedal pulsate, but this is normal.

If there is a problem with ABS, this warning light stays on. See Antilock Brake System (ABS) Warning Light on page 5‑28. If driving safely on a wet road and it becomes necessary to slam on the brakes and continue braking to avoid a sudden obstacle, a computer senses that the wheels are slowing down. If one of the wheels is about to stop rolling, the computer will separately work the brakes at each wheel. ABS can change the brake pressure to each wheel, as required, faster than any driver could. This can help the driver steer around the obstacle while braking hard.

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Braking in Emergencies ABS allows the driver to steer and brake at the same time. In many emergencies, steering can help more than even the very best braking.

Parking Brake

Set the parking brake by holding the regular brake pedal down, then pushing down the parking brake pedal.

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Brake Assist (Except With 4.3L V6 Engine) If this vehicle has StabiliTrak®, it also has a Brake Assist feature designed to assist the driver in stopping or decreasing vehicle speed in emergency driving conditions. This feature uses the stability system hydraulic brake control module to supplement the power brake system under conditions where the driver has quickly and forcefully applied the brake pedal in an attempt to quickly stop or slow down the vehicle. The stability system hydraulic brake control module increases brake pressure at each corner of the vehicle until the ABS activates.

If the ignition is on, the brake system warning light will come on. See Brake System Warning Light on page 5‑27. Notice: Driving with the parking brake on can overheat the brake system and cause premature wear or damage to brake system parts. Make sure that the parking brake is fully released and the brake warning light is off before driving. To release the parking brake, hold the regular brake pedal down, then push down momentarily on the parking brake pedal until you feel the pedal release. Slowly pull your foot up off the parking brake pedal. If the parking brake is not released when you begin to drive, the brake system warning light will flash and a chime will sound warning you that the parking brake is still on. If you are towing a trailer and are parking on a hill, see Driving Characteristics and Towing Tips on page 9‑91.

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Driving and Operating

Minor brake pedal pulsation or pedal movement during this time is normal and the driver should continue to apply the brake pedal as the driving situation dictates The Brake Assist feature will automatically disengage when the brake pedal is released or brake pedal pressure is quickly decreased.

Hill Start Assist (HSA) 2500 and 3500 series vehicles with StabiliTrak have a Hill Start Assist (HSA) feature, which may be useful when the vehicle is stopped on a grade. This feature is designed to prevent the vehicle from rolling, either forward or rearward, during vehicle drive off. After the driver completely stops and holds the vehicle in a complete standstill on a grade, HSA will be automatically

activated. During the transition period between when the driver releases the brake pedal and starts to accelerate to drive off on a grade, HSA holds the braking pressure for a maximum of two seconds to ensure that there is no rolling. The brakes will automatically release when the accelerator pedal is applied within the two‐second window. If the vehicle is equipped with the Integrated Trailer Brake Control (ITBC) system, HSA may also apply the trailer brakes. It will not activate if the vehicle is in a drive gear and facing downhill or if the vehicle is facing uphill and in R (Reverse). There may be situations on minor hills (less than 5% grade) with a loaded vehicle or while pulling a trailer where HSA will not activate.

Ride Control Systems

StabiliTrak® System The vehicle may have a vehicle stability enhancement system called StabiliTrak®. It is an advanced computer-controlled system that assists the driver with directional control of the vehicle in difficult driving conditions. StabiliTrak activates when the computer senses a discrepancy between the intended path and the direction the vehicle is actually traveling. StabiliTrak selectively applies braking pressure at any one of the vehicle's brakes to assist the driver with keeping the vehicle on the intended path.

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When the vehicle is started and begins to move, the system performs several diagnostic checks to insure there are no problems. The system may be heard or felt while it is working. This is normal and does not mean there is a problem with the vehicle. The system should initialize before the vehicle reaches 32 km/h (20 mph). In some cases, it may take approximately 3.2 km (2 mi) of driving before the system initializes. If cruise control is being used when StabiliTrak activates, the cruise control automatically disengages. The cruise control can be re-engaged when road conditions allow. See Cruise Control on page 9‑73 for more information. If the system fails to turn on or activate, the StabiliTrak light along with one of the following messages will be displayed on the Driver Information Center (DIC): TRACTION

CONTROL OFF, SERVICE TRACTION CONTROL, STABILITRAK OFF, SERVICE STABILITRAK. If these DIC messages appear, make sure the StabiliTrak system has not been turned off using the StabiliTrak on/off button. Then turn the vehicle off, wait 15 seconds, and turn it back on again to reset the system. If any of these messages still appear on the DIC, the vehicle should be taken in for service. For more information on the DIC messages, see Ride Control System Messages on page 5‑47.

The StabiliTrak light will flash on the instrument panel cluster when the system is both on and activated.

Driving and Operating

9-71

The system may be heard or felt while it is working; this is normal.

The traction control disable button is located on the instrument panel below the climate controls. The Traction Control System (TCS) part of StabiliTrak can be turned off by pressing and releasing the StabiliTrak button. To disable both TCS and StabiliTrak, press and hold 5 until F illuminates and the appropriate DIC message displays. TCS and StabiliTrak can be turned on by pressing and releasing the StabiliTrak button if they are not automatically shut off for any other reason.

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Driving and Operating

When TCS or StabiliTrak is turned off, the StabiliTrak light and the appropriate message will be displayed on the DIC to warn the driver. The vehicle will still have brake-traction control when traction control is off, but will not be able to use the engine speed management system. See “Traction Control Operation” next for more information. When the traction control system has been turned off, system noises may still be heard as a result of the brake-traction control coming on. It is recommended to leave the system on for normal driving conditions, but it may be necessary to turn the system off if the vehicle is stuck in sand, mud, ice or snow, and you want to “rock” the vehicle to attempt to free it. It may also be necessary to turn off the system when driving in extreme off-road conditions where high wheel spin is required. See If the Vehicle is Stuck on page 9‑23.

When the transfer case is in 4LO, the stability system is automatically disabled, the StabiliTrak light comes on, and the STABILITRAK OFF message will appear on the DIC. Both traction control and StabiliTrak are automatically disabled in this condition. Traction Control Operation The traction control system is part of the StabiliTrak system. Traction control limits wheel spin by reducing engine power to the wheels (engine speed management) and by applying brakes to each individual wheel (brake-traction control) as necessary. The traction control system is enabled automatically when the vehicle is started. It will activate and the StabiliTrak light will flash if it senses that any of the wheels are spinning or beginning to lose

traction while driving. If traction control is turned off, only the brake-traction control portion of traction control will work. The engine speed management will be disabled. In this mode, engine power is not reduced automatically and the driven wheels can spin more freely. This can cause the brake-traction control to activate constantly. Notice: If the wheel(s) of one axle is allowed to spin excessively while the StabiliTrak®, ABS, brake warning lights, and any relevant DIC messages are displayed, the transfer case could be damaged. The repairs would not be covered by the vehicle warranty. Reduce engine power and do not spin the wheel(s) excessively while these lights and messages are displayed.

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Driving and Operating

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The traction control system may activate on dry or rough roads or under conditions such as heavy acceleration while turning or abrupt upshifts/downshifts of the transmission. When this happens, a reduction in acceleration may be noticed, or a noise or vibration may be heard. This is normal. If cruise control is being used when the system activates, the StabiliTrak light will flash and cruise control will automatically disengage. Cruise control may be reengaged when road conditions allow. See Cruise Control on page 9‑73. StabiliTrak may also turn off automatically if it determines that a problem exists with the system. If the problem does not clear itself after restarting the vehicle, see your dealer for service.

2500 and 3500 series vehicles with StabiliTrak have a Trailer Sway Control (TSC) feature. See Trailer Sway Control (TSC) on page 9‑124. 2500 and 3500 series vehicles with StabiliTrak have a Hill Start Assist (HSA) feature. See Hill Start Assist (HSA) on page 9‑70. Adding non‐dealer accessories can affect the vehicle's performance. See Accessories and Modifications on page 10‑3.

Locking Rear Axle Vehicles with a locking rear axle can give more traction on snow, mud, ice, sand, or gravel. It works like a standard axle most of the time, but when traction is low, this feature will allow the rear wheel with the most traction to move the vehicle.

Cruise Control

{ WARNING

Cruise control can be dangerous where you cannot drive safely at a steady speed. So, do not use the cruise control on winding roads or in heavy traffic. Cruise control can be dangerous on slippery roads. On such roads, fast changes in tire traction can cause excessive wheel slip, and you could lose control. Do not use cruise control on slippery roads.

For vehicles with cruise control, a speed of about 40 km/h (25 mph) or more can be maintained without keeping your foot on the accelerator. Cruise control does not work at speeds below about 40 km/h (25 mph).

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Driving and Operating

When the brakes are applied, cruise control is turned off. For vehicles with an Allison or Hydra‐Matic 6‐speed automatic transmission, see “Grade Braking and Cruise Grade Braking (Allison Transmission) under Tow/Haul Mode on page 9‑51
for an explanation of how cruise control interacts with the Range Selection Mode, tow/haul and grade braking systems. For vehicles with the StabiliTrak system that begins to limit wheel spin while you are using cruise control, the cruise control will automatically disengage. See StabiliTrak® System on page 9‑70. When road conditions allow the cruise control to be safely used again, it can be turned back on.

[ (Cancel): Press to disengage cruise control without erasing the set speed from memory.

Setting Cruise Control If the cruise button is on when not in use, it could get bumped and go into cruise when not desired. Keep the cruise control switch off when cruise is not being used. The cruise control light on the instrument panel cluster will come on after the cruise control has been set to the desired speed. 1. Press I. 2. Get up to the desired speed. 3. Press the SET− button located

on the steering wheel and release it.

4. Take your foot off the

accelerator.

The cruise control buttons are located on the left side of the steering wheel. I (On/Off): Press to turn the system on or off. The indicator light is on when cruise control is on and turns off when cruise control is off. + RES (Resume/Accelerate): Press briefly to resume to a previously set speed, or press and hold to accelerate. SET − (Set/Coast): Press to set the speed and activate cruise control or make the vehicle decelerate.

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Driving and Operating

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Using Cruise Control on Hills How well the cruise control will work on hills depends upon the vehicle speed, load, and the steepness of the hills. While going up steep hills, you might have to step on the accelerator pedal to maintain the vehicle speed. While going downhill, you might have to brake or shift to a lower gear to keep the vehicle speed down. When the brakes are applied the cruise control is disengaged.

Reducing Speed While Using Cruise Control If the cruise control system is already activated, . Press and hold the SET– button

on the steering wheel until the desired lower speed is reached, then release it. To slow down in small amounts, press the SET– button on the steering wheel briefly. Each time this is done, the vehicle goes about 1.6 km/h (1 mph) slower.

Passing Another Vehicle While Using Cruise Control Use the accelerator pedal to increase the vehicle speed. When you take your foot off the pedal, the vehicle will slow down to the previous set cruise speed.

Resuming a Set Speed If the cruise control is set at a desired speed and then the brakes are applied, the cruise control is disengaged without erasing the set speed from memory. Once the vehicle speed reaches about 40 km/h (25 mph) or more, press the +RES button on the steering wheel. The vehicle returns to the previous set speed and stays there.

Increasing Speed While Using Cruise Control If the cruise control system is already activated, . Press and hold the +RES button

on the steering wheel until the desired speed is reached, then release it. To increase vehicle speed in small amounts, press the +RES button. Each time this is done, the vehicle goes about 1.6 km/h (1 mph) faster.

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Driving and Operating

Ending Cruise Control There are three ways to end cruise control:

To disengage cruise control; step lightly on the brake pedal.

. Press [ on the steering wheel.

To turn off the cruise control, press I on the steering wheel.

Erasing Speed Memory The cruise control set speed is erased from memory by pressing the I button or if the ignition is turned off.

Object Detection Systems

Ultrasonic Parking Assist For vehicles with the Ultrasonic Rear Parking Assist (URPA) system, it operates at speeds less than 8 km/h (5 mph), and assists the driver with parking and avoiding objects while in R (Reverse). The sensors on the rear bumper are used to detect the distance to an object up to 2.5 m (8 ft) behind the vehicle, and at least 25.4 cm (10 in) off the ground.

{ WARNING

The Ultrasonic Rear Parking Assist (URPA) system does not replace driver vision. It cannot detect:

. Objects that are below the

bumper, underneath the vehicle, or too close or far from the vehicle.

. Children, pedestrians,

bicyclists, or pets.

If you do not use proper care before and while backing, vehicle damage, injury, or death could occur. Even with URPA, always check behind the vehicle before backing up. While backing, be sure to look for objects and check the vehicle's mirrors.

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How the System Works URPA comes on automatically when the shift lever is moved into R (Reverse). A single tone sounds to indicate the system is working. URPA operates only at speeds less than 8 km/h (5 mph). An obstacle is indicated by audible beeps. The interval between the beeps becomes shorter as the vehicle gets closer to the obstacle. When the distance is less than 30 cm (12 in) the beeps are continuous. To be detected, objects must be at least 25.4 cm (10 in) off the ground and below tailgate level. Objects must also be within 2.5 m (8 ft) from the rear bumper. This distance may be less during warmer or humid weather.

Driving and Operating

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If this

When the System Does Not Seem to Work Properly The following messages may be displayed on the DIC: SERVICE PARK ASSIST: message occurs, take the vehicle to your dealer to repair the system. PARK ASSIST OFF: This message occurs if the driver disables the system. PARK ASST BLOCKED SEE OWNERS MANUAL: This message can occur under the following conditions:

The ultrasonic sensors are not clean. Keep the vehicle's rear bumper free of mud, dirt, snow, ice, and slush. For cleaning instructions, see “Washing the Vehicle” under Exterior Care on page 10‑108.

The system can be disabled by pressing the rear park aid disable button located next to the radio. The indicator light comes on and PARK ASSIST OFF displays on the Driver Information Center (DIC) to indicate that URPA is off; see Object Detection System Messages on page 5‑46. Notice: If you use URPA while the tailgate is lowered, it may not detect an object behind your vehicle, and you might back into the object and damage your vehicle. Always verify the tailgate is closed when using URPA or turn off URPA when driving with the tailgate lowered.

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Driving and Operating

The park assist sensors are covered by frost or ice. Frost or ice can form around and behind the sensors and may not always be seen; this can occur after washing the vehicle in cold weather. The message may not clear until the frost or ice has melted.

. A trailer was attached to the

vehicle, or a bicycle or an object was hanging out of the tailgate during the last drive cycle. Once the attached object is removed and the tailgate is raised, URPA will return to normal operation.

. A tow bar is attached to the

vehicle. The vehicle's bumper is damaged. Take the vehicle to your dealer to repair the system.

. Other conditions are affecting

system performance. Examples of this are vibrations from a jackhammer or the compression of air brakes on a very large truck.

Rear Vision Camera (RVC) This vehicle may have a Rear Vision Camera (RVC) system. Read this entire section before using it.

{ WARNING

The Rear Vision Camera (RVC) system does not replace driver vision. RVC does not:

. Detect objects that are

outside the camera's field of view, below the bumper, or underneath the vehicle.

. Detect children, pedestrians,

bicyclists, or pets.

Do not back the vehicle by only looking at the RVC screen, or use the screen during longer, higher

(Continued)

WARNING (Continued)

speed backing maneuvers or where there could be cross-traffic. Your judged distances using the screen will differ from actual distances. If you do not use proper care before backing up, you could hit a vehicle, child, pedestrian, bicyclist, or pet, resulting in vehicle damage, injury, or death. Even though the vehicle has the RVC system, always check carefully before backing up by checking behind and around the vehicle.

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Vehicles without Navigation System The Rear Vision Camera system is designed to help the driver when backing up by displaying a view of the area behind the vehicle. When the key is in the ON/RUN position and the driver shifts the vehicle into R (Reverse), the video image automatically appears on the inside rearview mirror. Once the driver shifts out of R (Reverse), the video image automatically disappears from the inside rearview mirror.

Turning the Rear Vision Camera System Off or On To turn off the RVC system, press and hold z, located on the inside rearview mirror, until the left indicator light turns off. The RVC display is now disabled.

To turn the RVC system on again, press and hold z until the left indicator light illuminates. The RVC system display is now enabled and the display will appear in the mirror normally. Vehicles with Navigation System The RVC system is designed to help the driver when backing up by displaying a view of the area behind the vehicle. When the driver shifts the vehicle into R (Reverse), the video image automatically appears on the navigation screen. Once the driver shifts out of R (Reverse), the navigation screen will go back to the last screen that had been displayed, after a delay.

Turning the Rear Vision Camera System On or Off To turn the RVC system on or off: 1. Shift into P (Park). 2. Press the MENU button to enter

the configure menu options, then press the MENU hard key to select Display or touch the Display screen button.

3. Select the Rear Camera Options screen button. The Rear Camera Options screen will display.

4. Select the Video screen

button. When the Video screen button is highlighted the RVC system is on.

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Driving and Operating

The delay after shifting out of R (Reverse) is approximately 10 seconds. The delay can be cancelled by performing one of the following: . Pressing a hard key on the

navigation system.

. Shifting into P (Park). . Reaching a vehicle speed of

8 km/h (5 mph).

There is a message on the rear vision camera screen that states “Check Surroundings for Safety.”

Adjusting the Brightness and Contrast of the Screen To adjust the brightness and contrast of the screen, press the MENU button while the rear vision camera image is on the display. Any adjustments made will only affect the rear vision camera screen.

] (Brightness): Touch the + (plus) or – (minus) screen buttons to increase or decrease the brightness of the screen. _ (Contrast): Touch the + (plus) or – (minus) screen buttons to increase or decrease the contrast of the screen.

Symbols The navigation system may have a feature that lets the driver view symbols on the navigation screen while using the RVC. The Ultrasonic Rear Park Assist (URPA) system must not be disabled to use the caution symbols. If URPA has been disabled and the symbols have been turned on, the Rear Parking Assist Symbols Unavailable error message may display. See Ultrasonic Parking Assist on page 9‑76.

The symbols appear when an object has been detected by the URPA system. The symbol may cover the object when viewing the navigation screen. To turn the symbols on or off: 1. Make sure that URPA has not

been disabled.

2. Shift into P (Park). 3. Press the MENU hard key

to enter the configure menu options, then press the MENU hard key repeatedly until Display is selected or touch the Display screen button.

4. Select the Rear Camera Options screen button. The Rear Camera Options screen will display. 5. Touch the Symbols screen

button. The screen button will be highlighted when on.

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Rear Vision Camera Error Messages Service Rear Vision Camera System: This message can display when the system is not receiving information it requires from other vehicle systems. If any other problem occurs or if a problem persists, see your dealer. Rear Vision Camera Location

The camera uses a special lens. The distance of the image that appears on the screen differs from the actual distance. The area displayed by the camera is limited. The camera does not display objects which are close to either corner of the bumper or under the bumper. The area displayed on the screen can vary according to vehicle orientation or road conditions.

Driving and Operating

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The following illustration shows the field of view that the camera provides.

A. View displayed by the camera B. Corner of the rear bumper

The rear vision camera is located in the bezel for the tailgate handle.

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9-82

Driving and Operating

Disconnecting the Rear Vision Camera The rear vision camera must be disconnected if the tailgate needs to be removed. To disconnect the camera: 1. Remove the license plate. 2. Disconnect the camera

connectors from the chassis harness, located behind the license plate, by pressing on the release tab on each connector.

A. Chassis harness connector B. Release tab C. Camera connector

3. Plug the two exposed chassis

harness connectors together to prevent contamination.

A. Chassis harness connector B. Release tab

4. Feed the wiring harness through

the pickup box, then plug the camera connectors together to prevent contamination.

5. Remove the tailgate.

See Tailgate on page 2‑10
for more information.

6. Reinstall the license plate. Reverse this procedure to reinstall the rear vision camera and make sure the grommet and connection are secure.

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Driving and Operating

9-83

When the System Does Not Seem to Work Properly The RVC system might not work properly or display a clear image if:

The RVC is turned off. See “Turning the Rear Camera System On or Off” earlier in this section. It is dark. The sun or the beam of headlights is shining directly into the camera lens. Ice, snow, mud, or anything else builds up on the camera lens. Clean the lens, rinse it with water, and wipe it with a soft cloth.

The back of the vehicle is in an accident. If this happens, the position and mounting angle of the camera can change or the camera can be affected. Be sure to have the camera and its position and mounting angle checked at your dealer.

The RVC system display in the rearview mirror may turn off or not appear as expected due to one of the following conditions. If this occurs the left indicator light on the mirror will flash. . A slow flash may indicate a

loss of video signal, or no video signal present during the reverse cycle.

. A fast flash may indicate that

the display has been on for the maximum allowable time during a reverse cycle, or the display has reached an Over Temperature limit. The fast flash conditions are used to protect the video device from high temperature conditions. Once conditions return to normal the device will reset and the green indicator will stop flashing.

During any of these fault conditions, the display will be blank and the indicator will continue to flash as long as the vehicle is in R (Reverse) or until the conditions return to normal. Pressing and holding z when the left indicator light is flashing will turn off the video display along with the left indicator light.

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9-84

Driving and Operating

Fuel For diesel engine vehicles, see “Fuel for Diesel Engines” in the Duramax Diesel Supplement. For Vehicles with gasoline engines, please read this.

Gasoline Use of the recommended fuel is an important part of the proper maintenance of this vehicle. To help keep the engine clean and maintain optimum vehicle performance, we recommend the use of gasoline advertised as TOP TIER Detergent Gasoline. Look for the TOP TIER label on the fuel pump to ensure gasoline meets enhanced detergency standards developed by auto companies. A list of marketers providing TOP TIER Detergent Gasoline can be found at www.toptiergas.com.

The eighth digit of the Vehicle Identification Number (VIN) shows the code letter or number that identifies the vehicle's engine. The VIN is at the top left of the instrument panel. See Vehicle Identification Number (VIN) on page 12‑1. Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85).

See Fuel E85 (85% Ethanol) on page 9‑87. For all other vehicles, use only the unleaded gasoline described under Recommended Fuel on page 9‑84.

Recommended Fuel For all vehicles except those with the 6.2L V8 engine (VIN Code 2), use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise, commonly referred to as spark knock, might be heard when driving. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service.

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If the vehicle has the 6.2L V8 engine (VIN Code 2), use premium unleaded gasoline with a posted octane rating of 91 or higher. You can also use regular unleaded gasoline rated at 87 octane or higher, but the vehicle's acceleration could be slightly reduced, and a slight audible knocking noise, commonly referred to as spark knock, might be heard. If the octane is less than 87, you might notice 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 could damage the engine. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service.

Gasoline Specifications (U.S. and Canada Only) At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/CGSB‐3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). We recommend against the use of gasolines containing MMT. See Fuel Additives on page 9‑86 for additional information.

Driving and Operating

9-85

California Fuel Requirements If the vehicle is certified to meet California Emissions Standards, it is designed to operate on fuels that meet California specifications. See the underhood emission control label. If this fuel is not available in states adopting California Emissions Standards, the vehicle will operate satisfactorily on fuels meeting federal specifications, but emission control system performance might be affected. The malfunction indicator lamp could turn on and the vehicle might fail a smog‐check test. See Malfunction Indicator Lamp on page 5‑25. If this occurs, return to your authorized dealer for diagnosis. If it is determined that the condition is caused by the type of fuel used, repairs might not be covered by the vehicle warranty.

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9-86

Driving and Operating

Fuels in Foreign Countries 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.

Fuel Additives To provide cleaner air, all gasolines in the United States are now required to contain additives that help prevent engine and fuel system deposits from forming, allowing the emission control system to work properly. In most cases, nothing should have to be added to the fuel. However, some gasolines contain only the minimum amount of

additive required to meet U.S. Environmental Protection Agency regulations. To help keep fuel injectors and intake valves clean and avoid problems due to dirty injectors or valves, look for gasoline that is advertised as TOP TIER Detergent Gasoline. Look for the TOP TIER label on the fuel pump to ensure gasoline meets enhanced detergency standards developed by the auto companies. A list of marketers providing TOP TIER Detergent Gasoline can be found at www.toptiergas.com. For customers who do not use TOP TIER Detergent Gasoline regularly, one bottle of GM Fuel System Treatment PLUS, added to the fuel tank at every engine oil change, can help clean deposits from fuel injectors and intake valves. GM Fuel System Treatment PLUS is the only gasoline additive recommended by General Motors. It is available at your dealer.

Gasolines containing oxygenates, such as ethers and ethanol, and reformulated gasolines might be available in your area. We recommend that you use these gasolines, if they comply with the specifications described earlier. However, E85 (85% ethanol) and other fuels containing more than 10% ethanol must not be used in vehicles that were not designed for those fuels. 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.

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Some gasolines that are not reformulated for low emissions can contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT); ask the attendant where you buy gasoline whether the fuel contains MMT. We recommend against the use of such gasolines. Fuels containing MMT can reduce spark plug life and affect emission control system performance. The malfunction indicator lamp might turn on. If this occurs, return to your dealer for service.

Fuel E85 (85% Ethanol) Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). For all other vehicles, use only the unleaded gasoline described under Recommended Fuel on page 9‑84.

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. 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.afdc.energy.gov/afdc/ locator/stations/) 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.

Driving and Operating

9-87

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 (3 gal) when refueling. You should drive the vehicle immediately after refueling for at least 11 km (7 mi) to allow the vehicle to adapt to the change in ethanol concentration.

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9-88

Driving and Operating

E85 has less energy per liter (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 9‑88. 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.

Filling the Tank If the vehicle has a diesel engine, see the Duramax diesel supplement 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.

The tethered fuel cap is located behind a hinged fuel door on the driver side of the vehicle. Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). See Fuel E85 (85% Ethanol) on page 9‑87. To remove the fuel cap, turn it slowly counterclockwise.

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Driving and Operating

9-89

{ 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 Exterior Care on page 10‑108. 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 5‑25. The TIGHTEN GAS CAP message displays on the Driver Information Center (DIC) if the fuel cap is not properly installed. See Fuel System Messages on page 5‑46 for more information.

{ 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 a new fuel cap is needed, be sure to get the right type of cap from your dealer. The wrong type of fuel cap might not fit properly, might cause the malfunction indicator lamp to light, and could damage the fuel tank and emissions system. See Malfunction Indicator Lamp on page 5‑25.

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9-90

Driving and Operating

Filling a Portable Fuel Container

{ WARNING

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.

(Continued)

WARNING (Continued)

Towing

. 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.

General Towing Information Only use towing equipment that has been designed for the vehicle. Contact your dealer or trailering dealer for assistance with preparing the vehicle for towing a trailer. See the following trailer towing information in this section:

For information on driving while towing a trailer, see “Driving Characteristics and Towing Tips.” For maximum vehicle and trailer weights, see “Trailer Towing.” For information on equipment to tow a trailer, see “Towing Equipment.”

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Driving and Operating

9-91

. Consider using a sway control.

. Vehicles can tow in D (Drive).

See “Hitches” under Towing Equipment on page 9‑112.

. Do not tow a trailer at all during

the first 800 km (500 miles) the new vehicle is driven. The engine, axle, or other parts could be damaged.

. During the first 800 km

(500 miles) that a trailer is towed, do not drive over 80 km/h (50 mph) and do not make starts at full throttle. This helps the engine and other parts of the vehicle wear in at the heavier loads.

Shift the transmission to a lower gear if the transmission shifts too often under heavy loads and/or hilly conditions.

Important considerations that have to do with weight: . Weight of the trailer . Weight of the trailer tongue . Weight on the vehicle's tires . Weight of the trailering

combination

For information on towing a disabled vehicle, see Towing the Vehicle on page 10‑103. For information on towing the vehicle behind another vehicle such as a motor home, see Recreational Vehicle Towing on page 10‑103.

Driving Characteristics and Towing Tips

Pulling a Trailer Important points for pulling a trailer:

There are many different laws, including speed limit restrictions, having to do with trailering. Make sure the rig will be legal, not only where you live but also where you will be driving. A good source for this information can be state or provincial police.

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Driving and Operating

Driving with a Trailer

{ WARNING

When towing a trailer, exhaust gases may collect at the rear of the vehicle and enter if the liftgate, trunk/hatch, or rear-most window is open. Engine exhaust contains Carbon Monoxide (CO) which cannot be seen or smelled. It can cause unconsciousness and even death. To maximize safety when towing a trailer:

. Have the exhaust system

inspected for leaks and make necessary repairs before starting a trip.

. Never drive with the liftgate,

trunk/hatch, or rear-most window open.

(Continued)

WARNING (Continued)

. Fully open the air outlets

on or under the instrument panel.

. Adjust the Climate Control

system to a setting that brings in only outside air and set the fan speed to the highest setting. See Climate Control System in the Index.

For more information about Carbon Monoxide, see Engine Exhaust on page 9‑44.

Towing a trailer requires a certain amount of experience. The combination you are driving is longer and not as responsive as the vehicle itself. Get acquainted with the handling and braking of the rig before setting out for the open road.

Before starting, check all trailer hitch parts and attachments, safety chains, electrical connectors, lamps, tires, and mirrors. If the trailer has electric brakes, start the combination moving and then apply the trailer brake controller by hand to be sure the brakes work. During the trip, check occasionally to be sure that the load is secure and the lamps and any trailer brakes still work. Following Distance Stay at least twice as far behind the vehicle ahead as you would when driving the vehicle without a trailer. This can help to avoid heavy braking and sudden turns.

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Passing More passing distance is needed when towing a trailer. The combination will not accelerate as quickly and is longer so it is necessary to go much farther beyond the passed vehicle before returning to the lane. Backing Up Hold the bottom of the steering wheel with one hand. To move the trailer to the left, 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. The vehicle could be damaged. Avoid making very sharp turns while trailering. When turning with a trailer, make wider turns than normal. Do this so the trailer will not strike soft shoulders, curbs, road signs, trees, or other objects. Avoid jerky or sudden maneuvers. Signal well in advance. If the trailer turn signal bulbs burn out, the arrows on the instrument panel will still flash for turns. It is important to check occasionally to be sure the trailer bulbs are still working.

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9-93

Driving on Grades Reduce speed and shift to a lower gear before starting down a long or steep downgrade. If the transmission is not shifted down, the brakes might get hot and no longer work well. Vehicles can tow in D (Drive). Shift the transmission to a lower gear if the transmission shifts too often under heavy loads and/or hilly conditions. The Tow/Haul Mode may be used if the transmission shifts too often. See Tow/Haul Mode on page 9‑51. 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 the engine is turned off immediately after towing at high altitude on steep uphill grades, the vehicle may show signs similar to engine overheating.

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9-94

Driving and Operating

To avoid this, let the engine run while parked, preferably on level ground, with the automatic transmission in P (Park) for a few minutes before turning the engine off. If the overheat warning comes on, see Engine Overheating on page 10‑25. Parking on Hills

{ WARNING

Parking the vehicle on a hill with the trailer attached can be dangerous. If something goes wrong, the rig could start to move. People can be injured, and both the vehicle and the trailer can be damaged. When possible, always park the rig on a flat surface.

If parking the rig on a hill: 1. Press the brake pedal, but

do not shift into P (Park) yet. Turn the wheels into the curb if facing downhill or into traffic if facing uphill.

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 brake pedal. Then

5.

apply the parking brake and shift into P (Park). If the vehicle is four-wheel-drive, be sure the transfer case is in a drive gear and not in N (Neutral).

6. Release the brake pedal.

{ WARNING

It can be dangerous to get out of the vehicle if the shift lever is not fully in P (Park) with the parking brake firmly set. The vehicle can roll. If the engine has been left running, the vehicle can move suddenly. You or others could be injured. To be sure the vehicle will not move, even when on fairly level ground, use the steps that follow. Always put the shift lever fully in P (Park) with the parking brake firmly set. If the transfer case on a four-wheel-drive vehicle is in N (Neutral), the vehicle will be free to roll, even if the shift lever is in P (Park). Be sure the transfer case is in a drive gear — not in N (Neutral).

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Leaving After Parking on a Hill 1. Apply and hold the brake pedal. 2. Start the engine. 3. Shift into a gear. 4. Release the parking brake. 5. Let up on the brake pedal. 6. Drive slowly until the trailer is

clear of the chocks.

7. Stop and have someone pick up

and store the chocks.

Maintenance when Trailer Towing The vehicle needs service more often when pulling a trailer. See this manual's Maintenance Schedule or Index for more information. Things that are especially important in trailer operation are automatic transmission fluid, engine oil, axle lubricant, belts, cooling system, and brake system. It is a good idea to inspect these before and during the trip. Check periodically to see that all hitch nuts and bolts are tight.

Trailer Towing If the vehicle has a diesel engine, see the Duramax diesel supplement for more information. If the vehicle is a hybrid, see the hybrid supplement for more information. Do not tow a trailer during break‐in. See New Vehicle Break-In on page 9‑34 for more information.

{ WARNING

The driver can lose control when pulling a trailer if the correct equipment is not used or the vehicle is not driven properly. For example, if the trailer is too heavy, the brakes may not work well or even at all. The driver and passengers could be seriously injured. The vehicle may also be damaged; the resulting repairs would not be covered by the

(Continued)

Driving and Operating

9-95

WARNING (Continued)

vehicle warranty. Pull a trailer only if all the steps in this section have been followed. Ask your dealer for advice and information about towing a trailer with the vehicle.

Notice: Pulling a trailer improperly can damage the vehicle and result in costly repairs not covered by the vehicle warranty. To pull a trailer correctly, follow the advice in this section and see your dealer