2012 GMC Sierra Owners Manual

instrument panel cluster warning and indicator lights. This position can also be used for service and

Driving and Operating

9-27

diagnostics, and to verify the proper operation of the malfunction indicator lamp as may be required for emission inspection purposes. The switch stays in this position when the engine is running. The transmission is also unlocked in this position on automatic transmission vehicles. If you leave the key in the ACC/ ACCESSORY or ON/RUN position with the engine off, the battery could be drained. You may not be able to start the vehicle if the battery is allowed to drain for an extended period of time. D (START): This is the position that starts the engine. When the engine starts, release the key. The ignition switch returns to ON/RUN for driving. A warning tone will sound when the driver door is opened and the ignition is in ACC/ACCESSORY or LOCK/OFF, and the key is in the ignition.

Starting the Engine 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. Notice: Do not try to shift to P (Park) if the vehicle is moving. If you do, you could damage the transmission. Shift to P (Park) only when the vehicle is stopped. Move the shift lever to P (Park) or N (Neutral). The engine will not start in any other position. To restart the engine when the vehicle is already moving, use N (Neutral) only. Notice: If you add electrical parts or accessories, you could change the way the engine operates. Any resulting damage would not be covered by the vehicle warranty. See Add-On Electrical Equipment on page 9‑105.

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Driving and Operating

Starting Procedure 1. With your foot off the accelerator

pedal, turn the ignition key to START. When the engine starts, let go of the key. The idle speed will go down as your engine gets warm. Do not race the engine immediately after starting it. Operate the engine and transmission gently to allow the oil to warm up and lubricate all moving parts. The vehicle has a Computer-Controlled Cranking System. This feature assists in starting the engine and protects components. If the ignition key is turned to the START position, and then released when the engine begins cranking, the engine will continue cranking for a few seconds or until the vehicle starts. If the engine does not start and the key is held in START for many seconds, cranking will be stopped after 15 seconds to prevent cranking motor damage. To prevent gear

damage, this system also prevents cranking if the engine is already running. Engine cranking can be stopped by turning the ignition switch to the ACC/ACCESSORY or LOCK/OFF position. When the Low Fuel warning lamp is on and the FUEL LEVEL LOW message is displayed in the Driver Information Center (DIC), the Computer-Controlled Cranking System is disabled to prevent possible vehicle component damage. When this happens, hold the ignition switch in the START position to continue engine cranking.

Notice: Cranking the engine for long periods of time, by returning the key to the START position immediately after cranking has ended, can overheat and damage the cranking motor, and drain the battery. Wait at least 15 seconds between each try, to let the cranking motor cool down.

2.

If the engine does not start after 5-10 seconds, especially in very cold weather (below −18°C or 0°F), it could be flooded with too much gasoline. Try pushing the accelerator pedal all the way to the floor and holding it there as you hold the key in START for up to 15 seconds. Wait at least 15 seconds between each try, to allow the cranking motor to cool down. When the engine starts, let go of the key and accelerator. If the vehicle starts briefly but then stops again, do the same thing. This clears the extra gasoline from the engine. Do not race the engine immediately after starting it. Operate the engine and transmission gently until the oil warms up and lubricates all moving parts.

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Driving and Operating

9-29

Retained Accessory Power (RAP) The following vehicle accessories can be used for up to 10 minutes after the engine is turned off: . Audio System . Power Windows . OnStar System (if equipped) . Sunroof (if equipped) These features work when the key is in ON/RUN or ACC/ ACCESSORY. Once the key is turned from ON/RUN to LOCK/OFF, the windows and sunroof continue to work up to 10 minutes until any door is opened. The radio continues to work for up to 10 minutes or until the driver door is opened.

Fast Idle System If the vehicle has this feature it is available only with cruise control. The manual fast idle switch is operated using the cruise control buttons located on the left hand side of the steering wheel. This system can be used to increase engine idle speed whenever the following conditions are met:

The park brake is set. The brake pedal is not pressed. The vehicle must not be moving and the accelerator must not be pressed.

To control the fast idle:

To enable the Fast Idle System, press and release the Cruise Control On/Off button and ensure that the switch LED is lit.

. Press and release the Cruise

Control Set switch. Engine speed will be held at approximately 1200 RPM.

When the fast idle is active the Driver Information Center (DIC) will display “FAST IDLE ON.” One of the following actions will turn off the fast idle: . Pressing the brake. . Selecting the Cruise Control

Cancel button.

. Releasing the Parking Brake. The transmission shift lever is moved out of P (Park) or N (Neutral).

. Selecting the Cruise Control

On/Off button when it was previously on.

. Pressing the Cruise Control Set

switch a second time.

. Pressing the accelerator greater than a quarter of the way down. Turning the ignition switch to the LOCK/OFF position.

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Driving and Operating

Engine Coolant Heater The engine heater can provide easier starting and better fuel economy during engine warm-up in cold weather conditions at or below −18°C (0°F). Vehicles with an engine heater should be plugged in at least four hours before starting. An internal thermostat in the plug-end of the cord may exist which will prevent engine coolant heater operation at temperatures above −18°C (0°F). If the vehicle has a diesel engine, see the Duramax Diesel supplement for more information. To Use the Engine Coolant Heater 1. Turn off the engine. 2. Open the hood and unwrap the electrical cord. The cord is secured to the Engine Compartment Fuse Block with a clip. Carefully remove the

wire tie which bundles the electrical plug. Do not cut the electrical cord.

3. Plug the cord into a normal, grounded 110-volt AC outlet.

{ WARNING Plugging the cord into an ungrounded outlet could cause an electrical shock. Also, the wrong kind of extension cord could overheat and cause a fire. You could be seriously injured. Plug the cord into a properly grounded three-prong 110-volt AC outlet. If the cord will not reach, use a heavy-duty three-prong extension cord rated for at least 15 amps.

4. Before starting the engine, be

sure to unplug and store the cord as it was before to keep it away from moving engine parts. If you do not, it could be damaged.

The length of time the heater should remain plugged in depends on several factors. Ask a dealer in the area where you will be parking the vehicle for the best advice on this.

Shifting Into Park { 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 you have left the engine running, the vehicle can move suddenly. You or others could be injured. To be sure the vehicle will not move, even when you are on fairly level ground, use the steps that follow. With four-wheel drive, if the transfer case is in N (Neutral), the vehicle will be free to roll, even if the shift lever is in P (Park). So, be sure the transfer case is in a drive

(Continued)

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WARNING (Continued)

gear — not in N (Neutral). If you are pulling a trailer, see Driving Characteristics and Towing Tips on page 9‑74.

1. Hold the brake pedal down, then

set the parking brake. See Parking Brake on page 9‑54
for more information.

2. Move the shift lever into the

P (Park) position by pulling the shift lever toward you and moving it up as far as it will go. 3. Be sure the transfer case is in a drive gear — not in N (Neutral).

4. Turn the ignition key to

LOCK/OFF.

5. Remove the key and take it with you. If you can leave the vehicle with the ignition key in your hand, the vehicle is in P (Park).

Leaving the Vehicle With the Engine Running

{ WARNING

It can be dangerous to leave the vehicle with the engine running. The vehicle could move suddenly if the shift lever is not fully in P (Park) with the parking brake firmly set. If you have four-wheel drive and the transfer case is in N (Neutral), the vehicle will be free to roll, even if the shift lever is in P (Park). So be sure the transfer case is in a drive gear — not in N (Neutral). And, if you leave the vehicle with the engine running, it could overheat and even catch fire. You or others could be injured. Do not leave the vehicle with the engine running unless you have to.

Driving and Operating

9-31

If you have to leave the vehicle with the engine running, be sure your vehicle is in P (Park) and the parking brake is firmly set before you leave it. After you move the shift lever into P (Park), hold the regular brake pedal down. Then, see if you can move the shift lever away from P (Park) without first pulling it toward you. If you can, it means that the shift lever was not fully locked into P (Park). Torque Lock If you are parking on a hill and you do not shift your transmission into P (Park) properly, the weight of the vehicle may put too much force on the parking pawl in the transmission. You may find it difficult to pull the shift lever out of P (Park). This is called torque lock. To prevent torque lock, set the parking brake and then shift into P (Park) properly before you leave the driver seat. To find out how, Shifting Into Park on page 9‑30.

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Driving and Operating

When you are ready to drive, move the shift lever out of P (Park) before you release the parking brake. If torque lock does occur, you may need to have another vehicle push yours a little uphill to take some of the pressure from the parking pawl in the transmission, then you will be able to pull the shift lever out of P (Park).

Shifting out of Park This vehicle is equipped with an electronic shift lock release system. The shift lock release is designed to: . Prevent ignition key removal

unless the shift lever is in P (Park) with the shift lever button fully released.

. Prevent movement of the shift

lever out of P (Park), unless the ignition is in ON/RUN or ACC/ ACCESSORY and the regular brake pedal is applied.

The shift lock release is always functional except in the case of an uncharged or low voltage (less than 9 volt) battery. If the vehicle has an uncharged battery or a battery with low voltage, try charging or jump starting the battery. See Jump Starting on page 10‑88 for more information. To shift out of P (Park) use the following: 1. Apply the brake pedal. 2. Move the shift lever to the

desired position.

If you still are unable to shift out of P (Park): 1. Ease the pressure on the shift

lever.

2. While holding down the brake pedal, press the shift lever all the way into P (Park).

3. Move the shift lever to the

desired position.

If you are still having a problem shifting, then have the vehicle serviced soon.

Parking over Things That Burn

{ WARNING

Things that can burn could touch hot exhaust parts under the vehicle and ignite. Do not park over papers, leaves, dry grass, or other things that can burn.

Active Fuel Management® Vehicles with V8 engines may have Active Fuel Management™. This system allows the engine to operate on either all or half of its cylinders, depending on the driving conditions.

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When less power is required, such as cruising at a constant vehicle speed, the system will operate in the half cylinder mode, allowing the vehicle to achieve better fuel economy. When greater power demands are required, such as accelerating from a stop, passing, or merging onto a freeway, the system will maintain full-cylinder operation. If the vehicle has an Active Fuel Management™ indicator, see Driver Information Center (DIC) on page 5‑30 for more information on using this display.

Driving and Operating

9-33

WARNING (Continued)

. There are holes or openings

in the vehicle body from damage or aftermarket modifications that are not completely sealed.

If unusual fumes are detected or if it is suspected that exhaust is coming into the vehicle:

. Drive it only with the windows

completely down.

. Have the vehicle repaired

immediately.

Never park the vehicle with the engine running in an enclosed area such as a garage or a building that has no fresh air ventilation.

Engine Exhaust { WARNING

Engine exhaust contains carbon monoxide (CO) which cannot be seen or smelled. Exposure to CO can cause unconsciousness and even death. Exhaust may enter the vehicle if:

. The vehicle idles in areas

with poor ventilation (parking garages, tunnels, deep snow that may block underbody airflow or tail pipes).

. The exhaust smells or

sounds strange or different.

. The exhaust system leaks

due to corrosion or damage. . The vehicle exhaust system has been modified, damaged or improperly repaired.

(Continued)

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Driving and Operating

Running the Vehicle While Parked It is better not to park with the engine running. But if you ever have to, here are some things to know.

{ WARNING

Idling a vehicle in an enclosed area with poor ventilation is dangerous. Engine exhaust may enter the vehicle. Engine exhaust contains carbon monoxide (CO) which cannot be seen or smelled. It can cause unconsciousness and even death. Never run the engine in an enclosed area that has no fresh air ventilation. For more information, see Engine Exhaust on page 9‑33.

{ WARNING

{ WARNING

It can be dangerous to get out of the vehicle if the automatic transmission shift lever is not fully in P (Park) with the parking brake firmly set. The vehicle can roll. Do not leave the vehicle when the engine is running unless you have to. If you have left the engine running, the vehicle can move suddenly. You or others could be injured. To be sure the vehicle will not move, even when you are on fairly level ground, always set the parking brake and move the shift lever to P (Park).

Four-wheel drive vehicles with the transfer case in N (Neutral) will allow the vehicle to roll, even if the automatic transmission shift lever is in P (Park). So, be sure the transfer case is in a drive gear — not in N (Neutral). Always set the parking brake.

Follow the proper steps to be sure the vehicle will not move. See Shifting Into Park on page 9‑30. If pulling a trailer, see Driving Characteristics and Towing Tips on page 9‑74.

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Automatic Transmission If the vehicle is a hybrid, see the hybrid supplement for more information. Vehicles with an automatic transmission have an electronic shift position indicator within the instrument panel cluster. This display comes on when the ignition key is turned to the ON/RUN position. There are several different positions for the shift lever.

Hydra-Matic® 4-Speed Automatic

Transmission

Heavy Duty 6-Speed Automatic Transmission Shown (Light Duty

6‐Speed Similar)

See “Range Selection Mode” under Manual Mode on page 9‑38. P (Park): This position locks the rear wheels. It is the best position to use when starting the engine because the vehicle cannot move easily. When parked on a hill, especially when the vehicle has a heavy load, you might notice an increase in the effort to shift out of P (Park). See “Torque Lock” under Shifting Into Park on page 9‑30 for more information.

Driving and Operating

9-35

{ WARNING

It is 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. Do not leave the vehicle when the engine is running unless you have to. If you have left the engine running, the vehicle can move suddenly. You or others could be injured. To be sure the vehicle will not move, even when you are on fairly level ground, always set the parking brake and move the shift lever to P (Park). See Shifting Into Park on page 9‑30. If you are pulling a trailer, see Driving Characteristics and Towing Tips on page 9‑74.

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Driving and Operating

{ WARNING

If you have Four-Wheel Drive, the vehicle will be free to roll — even if the shift lever is in P (Park) — if the transfer case is in Neutral. So, be sure the transfer case is in a drive gear, Two-Wheel Drive High or Four-Wheel Drive High or Four-Wheel Drive Low — not in Neutral. See Shifting Into Park on page 9‑30.

R (Reverse): Use this gear to back up. Notice: Shifting to R (Reverse) while the vehicle is moving forward could damage the transmission. The repairs would not be covered by the vehicle warranty. Shift to R (Reverse) only after the vehicle is stopped. To rock the vehicle back and forth to get out of snow, ice, or sand without damaging the transmission, see If the Vehicle Is Stuck on page 9‑15.

N (Neutral): In this position, the engine does not connect with the wheels. To restart when you are already moving, use N (Neutral) only. Also, use N (Neutral) when the vehicle is being towed.

{ WARNING

Shifting into a drive gear while the engine is running at high speed is dangerous. Unless your foot is firmly on the brake pedal, the vehicle could move very rapidly. You could lose control and hit people or objects. Do not shift into a drive gear while the engine is running at high speed.

Notice: Shifting out of P (Park) or N (Neutral) with the engine running at high speed may damage the transmission. The repairs would not be covered by the vehicle warranty. Be sure the engine is not running at high speed when shifting the vehicle.

D (Drive): This position is for normal driving. It provides the best fuel economy. If you need more power for passing, and you are: . Going less than about 55 km/h (35 mph), push the accelerator pedal about halfway down.

. Going about 55 km/h (35 mph) or

more, push the accelerator all the way down. By doing this, the vehicle shifts down to the next gear and has more power.

D (Drive) can be used when towing a trailer, carrying a heavy load, driving on steep hills, or for off-road driving. You might want to shift the transmission to a lower gear selection if the transmission shifts too often. Downshifting the transmission in slippery road conditions could result in skidding. See “Skidding” under Loss of Control on page 9‑5.

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Driving and Operating

9-37

vehicle is being used, such as with a heavy load or when temperature changes. During this adaptive shift control process, shifting might feel different as the transmission determines the best settings. When temperatures are very cold, the Allison Transmission and Hydra-Matic 6-Speed transmission's gear shifting could be delayed providing more stable shifts until the engine warms up. Shifts could be more noticeable with a cold transmission. This difference in shifting is normal. M (Manual Mode): This position is available on vehicles with the Allison Transmission or Hydra-Matic 6-Speed transmission. It lets drivers select the range of gears appropriate for current driving conditions. If the vehicle has this feature, see “Range Selection Mode” under Manual Mode on page 9‑38.

3 (Third): This position is also used for normal driving. It reduces vehicle speed more than D (Drive) without using the brakes. You might choose 3 (Third) instead of D (Drive) when driving on hilly, winding roads, when towing a trailer, so there is less shifting between gears and when going down a steep hill. 2 (Second): This position reduces vehicle speed even more than 3 (Third) without using the brakes. You can use 2 (Second) on hills. It can help control vehicle speed as you go down steep mountain roads, but then you would also want to use the brakes off and on. If you manually select 2 (Second) in an automatic transmission, the transmission will start in second gear. You can use this feature for reducing the speed of the rear wheels when you are trying to start the vehicle from a stop on slippery road surfaces.

The vehicle has a shift stabilization feature that adjusts the transmission shifting to the current driving conditions in order to reduce rapid upshifts and downshifts. This shift stabilization feature is designed to determine, before making an upshift, if the engine is able to maintain vehicle speed by analyzing things such as vehicle speed, throttle position, and vehicle load. If the shift stabilization feature determines that a current vehicle speed cannot be maintained, the transmission does not upshift and instead holds the current gear. In some cases, this could appear to be a delayed shift, however the transmission is operating normally. The transmission uses adaptive shift controls. Adaptive shift controls continually compares key shift parameters to pre-programmed ideal shifts stored in the transmissions computer. The transmission constantly makes adjustments to improve vehicle performance according to how the

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Driving and Operating

1 (First): For the Hydra-Matic 4-Speed transmission this position reduces vehicle speed even more than 2 (Second) without using the brakes. You can use it on very steep hills, or in deep snow or mud. If the shift lever is put in 1 (First) while the vehicle is moving forward, the transmission does not shift into first gear until the vehicle is going slowly enough. For an Allison Transmission or Hydra-Matic 6-Speed transmission, this position reduces vehicle speed without using the brakes. You can use it for major/severe downgrades and off-road driving where the vehicle would otherwise accelerate due to steepness of grade. When you shift to 1 (First) it provides the lowest gear appropriate to current road speed and continues to downshift as the vehicle slows, eventually downshifting to 1 (First) gear.

Notice: Spinning the tires or holding the vehicle in one place on a hill using only the accelerator pedal may damage the transmission. The repair will not be covered by the vehicle warranty. If you are stuck, do not spin the tires. When stopping on a hill, use the brakes to hold the vehicle in place.

Manual Mode

Range Selection Mode (Allison® Transmission or Hydra-Matic® 6-Speed Transmission)

The vehicle may have a Range Selection Mode. The Range Selection Mode helps control the

vehicle's transmission and vehicle speed while driving down hill or towing a trailer by letting you select a desired range of gears. To use this feature, do the following: 1. Move the shift lever to

M (Manual Mode).

2. Press the plus/minus buttons, located on the steering column shift lever, to select the desired range of gears for current driving conditions.

When M (Manual Mode) is selected a number displays next to the M, indicating the current gear. This number is the highest gear that can be used. However, the vehicle can automatically shift to lower gears as it adjusts to driving conditions. This means that all gears below that number are available. When 5 (Fifth) is selected, 1 (First) through 5 (Fifth) gears are automatically shifted by the vehicle, but 6 (Sixth) cannot be used until

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Driving and Operating

9-39

the plus/minus button located on the steering column lever is used to change to the gear. Grade Braking is not available when Range Selection Mode is active. See Tow/Haul Mode on page 9‑39. While using Range Selection Mode, Cruise Control and the Tow/Haul Mode can be used. If the vehicle has an exhaust brake, it can also be used, but will not automatically downshift the transmission. See Exhaust Brake in the Duramax Diesel supplement. Notice: Spinning the tires or holding the vehicle in one place on a hill using only the accelerator pedal may damage the transmission. The repair will not be covered by the vehicle warranty. If you are stuck, do not spin the tires. When stopping on a hill, use the brakes to hold the vehicle in place.

Low Traction Mode If your vehicle has the Allison Transmission, or the Hydra-Matic 6-Speed Automatic Transmission, it has a Low Traction Mode that can assist in vehicle acceleration when road conditions are slippery, such as with ice or snow. While the vehicle is at a stop, select the second gear range using Range Selection Mode. This will limit torque to the wheels after it detects wheel slip, preventing the tires from spinning.

Tow/Haul Mode

4-Speed Automatic Transmission

6-Speed Automatic Transmission Vehicles with an automatic transmission have a Tow/Haul Mode. The Tow/Haul Mode adjusts the transmission shift pattern to reduce shift cycling, providing increased performance, vehicle control, and transmission cooling when driving down steep hills or Mountain grades, towing, or hauling heavy loads. The selector button is located on the end of the shift lever. Turn the Tow/Haul Mode on and off by pressing the button. When the Tow/Haul Mode is enabled, a light on the instrument panel cluster will come on.

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Driving and Operating

See Tow/Haul Mode Light on page 5‑26 and Hill and Mountain Roads on page 9‑12 for more information. Also see “Tow/Haul Mode” under Towing Equipment on page 9‑94 for more information. Grade Braking (6-Speed Automatic Transmission) The Grade Braking shift modes can be activated by pressing the button on the end of the shift control lever. While in Range Selection Mode, Grade Braking is deactivated allowing the driver to select a desired range of gears. Grade Braking is only active while the Tow/Haul Mode is selected and you are not in the Range Selection Mode. See “Tow/Haul Mode” listed previously and Manual Mode on page 9‑38 for more information on

the Range Selection Mode. Grade Braking assists in maintaining desired vehicle speeds when driving on downhill grades by automatically implementing a shift schedule that utilizes the engine and transmission to slow the vehicle. This reduces wear on the braking system and increases control of the vehicle. Grade Braking monitors vehicle speed, acceleration, engine torque and brake pedal usage. Using this information, it detects when the truck is on a downhill grade and the driver desires to slow the vehicle by pressing the brake. This feature is active when the exhaust brake is enabled (if equipped). Also see Towing Equipment on page 9‑94 for more information.

Drive Systems

Four-Wheel Drive If the vehicle has Four-Wheel Drive, you can send the engine's driving power to all four wheels for extra traction. To get the most satisfaction out of Four-Wheel Drive, you must be familiar with its operation. Read the following before using Four-Wheel Drive. See the appropriate text for the transfer case in the vehicle. Notice: Driving on clean, dry pavement in Four-Wheel Drive High or Four-Wheel Drive Low for an extended period of time may cause premature wear on the vehicle's powertrain. Do not drive on clean, dry pavement in Four-Wheel Drive High or Four-Wheel Drive Low for extended periods of time.

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While driving on clean dry pavement and during tight turns, you may experience vibration in the steering system. If the vehicle has StabiliTrak®, shifting into Four-Wheel Drive Low will turn Traction Control and StabiliTrak off. See StabiliTrak® System on page 9‑55. Front Axle The front axle engages and disengages automatically when you shift the transfer case. Some delay for the axle to engage or disengage is normal.

Driving and Operating

9-41

Manual Transfer Case

A Four-Wheel Drive indicator light comes on when you shift into four-wheel drive and the front axle engages. See Four-Wheel-Drive Light on page 5‑26. Some delay between shifting and when the indicator light comes on is normal.

The transfer case shift lever is on the floor to the right of the driver. Use this lever to shift into and out of Four-Wheel Drive.

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Driving and Operating

Recommended Transfer Case Settings

Driving Conditions

Normal Severe Extreme

Vehicle in Tow*

Transfer Case Settings

4m

4n

2m

YES

YES

YES

YES

*See Recreational Vehicle Towing on page 10‑93 or Towing the Vehicle on page 10‑93.

Notice: Driving on clean, dry pavement in four-wheel drive for an extended period of time can cause premature wear on the vehicle's powertrain. Do not drive on clean, dry pavement in Four-Wheel Drive for extended periods of time.

4 n (Four-Wheel Drive Low): This setting also engages the front axle and delivers extra torque. You may never need Four-Wheel Drive Low. 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 9‑55.

A parking brake symbol is located next to the N (Neutral) symbol as a reminder to set the parking brake before shifting the transfer case into N (Neutral).

{ 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

(Continued)

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Driving and Operating

9-43

WARNING (Continued)

before placing the transfer case in N (Neutral). See Parking Brake on page 9‑54.

N (Neutral): Shift to this setting only when the vehicle needs to be towed. See Recreational Vehicle Towing on page 10‑93 or Towing the Vehicle on page 10‑93. 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. 4 m (Four-Wheel Drive High): Use this setting when you need extra traction, such as on snowy or icy roads or in most off-road situations. This setting also engages the front axle to help drive your vehicle. This is the best setting to use when plowing snow.

You can shift from Two-Wheel Drive High to Four-Wheel Drive High or Four-Wheel Drive High to Two-Wheel Drive High while the vehicle is moving. In extremely cold weather, it may be necessary to stop or slow the vehicle to shift into Four-Wheel Drive High.

When Using the Manual Transfer Case . Shifts into or out of Four-Wheel Drive Low or N (Neutral) should be made using quick motions to avoid excessive gear grinding. Shifting slowly may make it more difficult to shift.

. You may notice that it is harder to shift when the vehicle is cold. After the vehicle warms up the shifting will return to normal. . While in Four-Wheel High or

Four-Wheel Drive Low you may experience reduced fuel economy.

. Avoid driving in Four-Wheel

Drive on clean, dry pavement. It may cause your tires to wear faster, make the transfer case harder to shift, and run noisier. If the transfer case shifter is in the N (Neutral) position and you have difficulty reaching the selected transfer case mode, with the engine running, shift the transmission momentarily to D (Drive) and then back to N (Neutral). This will realign the gear teeth in the transfer case and allow you to complete the shift.

Shifting from Two-Wheel Drive High to Four-Wheel Drive High . Shifts between Two-Wheel Drive High and Four-Wheel Drive High can be made at any vehicle speed.

. Shift the transfer case lever in

one continuous motion into either the Four-Wheel Drive High or Two-Wheel Drive High position.

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Driving and Operating

. Shifting from Two-Wheel Drive High to Four-Wheel Drive High while the vehicle is in motion may require that moderate force be applied to the shift lever for a few seconds before Four-Wheel Drive High can be engaged, especially in cold weather. In extremely cold weather, it may be necessary to slow or stop the vehicle to shift into Four-Wheel Drive High.

. While in Four-Wheel Drive High, the vehicle can be driven at any posted legal speed limit.

Shifting In or Out of Four-Wheel Drive Low Notice: Shifting the transfer case into Four-Wheel-Drive Low while moving at speeds faster than 5 km/h (3 mph) may cause premature wear to the transfer case, and may cause the gears to grind. To avoid causing premature wear, and grinding the gears, do not shift the transfer

case into Four-Wheel-Drive Low while the vehicle is moving faster than 5 km/h (3 mph). . Shifting into Four-Wheel Drive

Low should be done, if possible, with the vehicle at a slight roll, 5 km/h (3 mph) or less.

. Shift the transmission into

N (Neutral).

{ 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 9‑54.

. Shifting into Four-Wheel Drive Low with the vehicle at a stop may be more difficult. You may be unable to complete the shift to Four-Wheel Drive Low, and

the transfer case will end up in N (Neutral). This is normal, and is a function of the gear teeth aligning in the transfer case. When this happens, make sure the engine is on, shift the transmission momentarily to D (Drive) and back to N (Neutral), and then complete the transfer case shift.

. Shift the transfer case shift lever

in one continuous motion into the Four-Wheel Drive Low position.

. When in Four-Wheel Drive

Low do not drive faster than 72 km/h (45 mph). This will reduce wear and extend the life of your transfer case.

Shifting In or Out of Neutral 1. With the vehicle running and the engine at an idle, set the parking brake.

2. Place the transmission into

N (Neutral).

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Shift the transfer case in one continuous motion into or out of the N (Neutral) position. Electronic 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

9-45

Recommended Transfer Case Settings

Driving Conditions

Normal Severe Extreme

Vehicle in Tow*

Transfer Case Settings

4m

4n

2m

YES

YES

YES

YES

*See Recreational Vehicle Towing on page 10‑93 or Towing the Vehicle on page 10‑93.

You can choose among four 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 flashes while shifting the transfer case and remains 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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9-46

Driving and Operating

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 while 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 9‑55.

{ 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 9‑54.

N (Neutral): Shift the vehicle's transfer case to N (Neutral) only when towing the vehicle. See Recreational Vehicle Towing on page 10‑93 or Towing the Vehicle on page 10‑93 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” under Transmission Messages on page 5‑46.

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. See “Shifting Out of Four-Wheel Drive Low” for more information.

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

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Four-Wheel Drive Low indicator light to stop flashing and remain on before shifting the transmission in 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 transfer case 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 more than 5 km/h (3 mph), the Four-Wheel Drive Low indicator light will flash for 30 seconds and not complete the shift.

After 30 seconds the transfer case will shift to Four-Wheel Drive High mode.

Shifting Out of Four-Wheel Drive Low To shift from Four-Wheel Drive Low to Four-Wheel Drive High, 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 or Two-Wheel Drive High position. You must wait for the Four-Wheel Drive High or Two-Wheel Drive High indicator light to stop flashing and remain on before shifting the transmission into gear.

Driving and Operating

9-47

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 transfer case N (Neutral) with the engine running. If the knob is turned to the Four-Wheel Drive High, or Two-Wheel Drive High switch position when the vehicle is in gear and/or moving more than 5 km/h (3 mph), the Four-Wheel Drive High, AUTO, or Two-Wheel Drive High indicator light will flash for 30 seconds but will not complete the shift.

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9-48

Driving and Operating

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 press

and hold the regular brake pedal. See Parking Brake on page 9‑54 for more information.

3. Start the vehicle or turn the

ignition to ON/RUN.

4. Shift the transmission to

N (Neutral).

5. Shift the transfer case to

Two-Wheel Drive High.

6. Turn the transfer case dial

clockwise to N (Neutral) until it stops and hold it there until the 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.

7.

If the engine is running, verify 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.

8. Turn the ignition to ACC/

ACCESSORY, which will turn the engine off.

9. Place the transmission shift

lever in P (Park).

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.

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.

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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. 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

Driving and Operating

9-49

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. 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.

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9-50

Driving and Operating

If the vehicle has StabiliTrak®, shifting into Four-Wheel Drive Low will turn Traction Control and StabiliTrak off. See StabiliTrak® System on page 9‑55.

{ 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 9‑54.

N (Neutral): Shift the vehicle's transfer case to N (Neutral) only when towing the vehicle. See Recreational Vehicle Towing on page 10‑93 or Towing the Vehicle on page 10‑93 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” under Transmission Messages on page 5‑46.

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.

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.

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Driving and Operating

9-51

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 Low position when the vehicle is in gear and/or moving more than 5 km/h (3 mph), the Four-Wheel Drive Low indicator light will flash for 30 seconds and not complete the shift. After 30 seconds the transfer case will shift to Four-Wheel Drive High mode.

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 more than 5 km/h (3 mph), the Four-Wheel Drive High, AUTO or Two-Wheel Drive High indicator light will flash for 30 seconds but will not complete the shift.

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9-52

Driving and Operating

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 9‑54 for more information.

3. Start the vehicle or turn the

ignition in ON/RUN.

4. Put the transmission in

N (Neutral).

5. Shift the transfer case to

Two-Wheel Drive High.

6. Turn the transfer case dial

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.

7.

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.

8. Turn the ignition to ACC/

ACCESSORY, which will turn the engine off.

9. Place the transmission shift

lever in P (Park).

10. Release the parking brake prior

to moving the vehicle.

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.

4. Release the parking brake prior

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.

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Driving and Operating

9-53

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.

If there is a problem with ABS, this warning light stays on. See Antilock Brake System (ABS) Warning Light on page 5‑26.

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. 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. 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.

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9-54

Driving and Operating

Parking Brake

Set the parking brake by holding the regular brake pedal down, then pushing down the parking brake pedal. If the ignition is on, the brake system warning light will come on. See Brake System Warning Light on page 5‑25. 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 9‑74.

Brake Assist 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. 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) Non‐hybrid vehicles with StabiliTrak have a Hill Start Assist (HSA) feature, which may be useful when the vehicle is stopped on a grade.

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Driving and Operating

9-55

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 has 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. StabiliTrak is on automatically whenever the vehicle is started. To assist with directional control of the vehicle, the system should always be left on. Trailer Sway Control (TSC) is also on automatically when

the vehicle is started. See Trailer Sway Control (TSC) on page 9‑105
for more information. 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 9‑58. If the system fails to turn on or activate, the StabiliTrak light along with a message will be displayed on the Driver Information Center (DIC).

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9-56

Driving and Operating

If a DIC message appears, make sure the StabiliTrak system has not been turned off using the Traction Control System (TCS)/StabiliTrak button. Then turn the vehicle off, wait 15 seconds, and then turn it back on again to reset the system. If any of the 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 5‑44.

The TCS/StabiliTrak button is located on the instrument panel. The traction control part of StabiliTrak can be turned off by pressing and releasing the TCS/ StabiliTrak button if both systems (traction control and StabiliTrak) were previously on.

The StabiliTrak light will flash on the instrument panel cluster when the system or the TSC feature is both on and activated. The system may be heard or felt while it is working; this is normal.

To disable both TCS and StabiliTrak, press and hold the TCS/StabiliTrak button until the StabiliTrak OFF light illuminates and

the appropriate DIC message displays. This will also disable the TSC feature. Traction control and StabiliTrak can be turned on by pressing and releasing the TCS/StabiliTrak button if they are not automatically shut off for any other reason. This will also enable the TSC feature. When the TCS or StabiliTrak system 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 TCS has been turned off, system noises may still be heard as a result of the brake-traction control coming on.

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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