2016 GMC Sierra Owners Manual

pressure. Do not pump the brakes repeatedly. This may deplete power assist, requiring increased brake pedal force.

2. Shift the vehicle to N (Neutral).

This can be done while the vehicle is moving. After shifting

to N (Neutral), firmly apply the brakes and steer the vehicle to a safe location.

3. Come to a complete stop, shift

to P (Park), and turn the ignition to LOCK/OFF. On vehicles with an automatic transmission, the shift lever must be in P (Park) to turn the ignition switch to the LOCK/ OFF position.

4. Set the parking brake. See

Parking Brake 0 300. { Warning

Turning off the vehicle while moving may cause loss of power assist in the brake and steering systems and disable the airbags. While driving, only shut the vehicle off in an emergency.

If the vehicle cannot be pulled over, and must be shut off while driving, turn the ignition to ACC/ ACCESSORY.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

Caution

Using a tool to force the key to turn in the ignition could cause damage to the switch or break the key. Use the correct key, make sure it is all the way in, and turn it only with your hand. If the key cannot be turned by hand, see your dealer.

1 (ACC/ACCESSORY) : This position lets things like the radio and the windshield wipers operate while the engine is off. It also unlocks the steering wheel. Use this position if the vehicle must be pushed or towed. 2 (ON/RUN) : This position can be used to operate the electrical accessories and to display some instrument cluster warning and indicator lights. This position can also be used for service and 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 the key is left in the ACC/ ACCESSORY or ON/RUN position with the engine off, the battery could be drained. The vehicle may not start if the battery is allowed to drain for an extended period of time. 3 (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 an eAssist vehicle, see the Silverado/Sierra eAssist supplement.

Driving and Operating

277

Caution

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 0 348.

Caution

If the steering wheel is turned until it reaches the end of its travel, and is held in that position while starting the vehicle, damage may occur to the hydraulic power steering system and there may be loss of power steering assist.

Move the shift lever to P (Park) or N (Neutral). To restart the engine when the vehicle is already moving, use N (Neutral) only.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

278

Driving and Operating

Caution

Caution

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.

Starting Procedure 1. Turn the ignition key to START. When the engine starts, let go of the key. The idle speed will go down as the 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. When the low fuel warning light is on and the FUEL LEVEL LOW message is displayed in the Driver Information Center (DIC), hold the ignition switch in the START position to continue engine cranking.

Cranking the engine for long periods of time, by returning the ignition 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 five to 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 while holding 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.

Fast Idle System If equipped, this feature is available only with cruise control. The manual fast idle switch is operated using the cruise control buttons on the left side of the steering wheel. This system can be used to increase engine idle speed whenever the following conditions are met: . The parking brake is set. . The brake pedal is not pressed. . The vehicle must not be moving and the accelerator must not be pressed.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

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 indicator light is lit.

. Press and release the cruise control SET- button. Engine speed will be held at approximately 1200 rpm.

One of the following actions will turn off the fast idle: . Pressing the brake. . Selecting the cruise control

cancel button.

. Releasing the parking brake. . Moving the transmission shift

lever out of P (Park) or N (Neutral).

. Selecting the cruise control on/

off button when it was previously on.

. Pressing the cruise control SET-

button a second time.

. Pressing the accelerator more

than one-quarter of the way down.

. Turning the ignition switch to the

LOCK/OFF position.

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 or until any door is opened. The radio continues to work for up to 10 minutes or until the driver door is opened.

Driving and Operating

279

Accessory Power Outlets (APOs) The vehicle may have APOs in several locations. See Power Outlets 0 125. The APOs in the console or center seat position are powered by RAP. They will continue to work for up to 10 minutes after the key is turned from ON/RUN to LOCK/OFF, or until the driver door is opened. The APOs on the center stack come from the factory powered directly from the vehicle battery, and supply accessory power at all times, regardless of ignition key position. If electronic items are left plugged into these APOs for long periods of time with the vehicle off, the vehicle battery could be drained. The vehicle may not start if the battery is allowed to drain for an extended period of time.

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

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

280

Driving and Operating

−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. 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 driver side fender with a clip, next to the engine compartment fuse block. Carefully remove the wire tie that bundles the electrical plug. Do not cut the electrical cord. Check the heater cord for damage. If it is damaged, do not use it. See your dealer for a replacement. Inspect the cord for damage yearly.

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

{ Warning

Improper use of the heater cord or an extension cord can damage the cord and may result in overheating and fire.

. Plug the cord into a

three-prong electrical utility receptacle that is protected by a ground fault detection function. An ungrounded outlet could cause an electric shock.

. Use a weatherproof,

heavy-duty, 15 amp-rated extension cord if needed. Failure to use the recommended extension cord in good operating condition, or using a damaged heater or extension cord, could make

(Continued)

Warning (Continued)

it overheat and cause a fire, property damage, electric shock, and injury.

. Do not operate the vehicle

with the heater cord permanently attached to the vehicle. Possible heater cord and thermostat damage could occur.

. While in use, do not let the

heater cord touch vehicle parts or sharp edges. Never close the hood on the heater cord.

. Before starting the vehicle,

unplug the cord, reattach the cover to the plug, and securely fasten the cord. Keep the cord away from any moving parts.

4. Before starting the engine, be

sure to unplug and store the cord as it was before to keep it

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

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

(Continued)

Warning (Continued)

is in P (Park). Be sure the transfer case is in a drive gear. If towing a trailer, see Driving Characteristics and Towing Tips 0 321.

1. Hold the brake pedal down, then set the parking brake. See Parking Brake 0 300.

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 (if

equipped) 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).

Driving and Operating

281

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.

If you have to leave the vehicle with the engine running, be sure the vehicle is in P (Park) and the

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

282

Driving and Operating

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 the 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, see Shifting Into Park 0 281. 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. You will then 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).

. Prevent movement of the shift

lever out of P (Park), unless the ignition is in ON/RUN 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 - North America 0 432.

To shift out of P (Park): 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. This vehicle may have the Safety Belt Assurance System, which may prevent the vehicle from shifting out of P (Park). See Safety Belt Messages 0 157.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

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 a V8 or V6 gasoline engine may have Active Fuel Management. This system allows the engine to operate on either all of its cylinders, or in V4 mode, depending on the driving conditions.

When less power is required, such as cruising at a constant vehicle speed, the system will operate in the V4 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) (Base Level) 0 146 or Driver Information Center (DIC) (Uplevel) 0 148 for more information on using this display.

Driving and Operating

283

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)

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

284

Driving and Operating

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.

Running the Vehicle While Parked It is better not to park with the engine running. If the vehicle is left with the engine running, follow the proper steps to be sure the vehicle will not move. See Shifting Into Park 0 281 and Engine Exhaust 0 283. If parking on a hill and pulling a trailer, see Driving Characteristics and Towing Tips 0 321.

Automatic Transmission If equipped, there is an electronic shift lever position indicator within the instrument 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.

Heavy-Duty 6-Speed Automatic Transmission Shown, Others

Similar

See “Range Selection Mode” under Manual Mode 0 288. P : 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

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

effort to shift out of P (Park). See “Torque Lock” under Shifting Into Park 0 281.

{ 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. 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 0 281 and Driving Characteristics and Towing Tips 0 321.

{ 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 N (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 N (Neutral). See Shifting Into Park 0 281.

R : Use this gear to back up.

Caution

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.

Driving and Operating

285

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 0 266. N : 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.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

286

Driving and Operating

Caution

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 : 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.

Use D (Drive) and Tow/Haul Mode when towing a trailer, carrying a heavy load, driving on steep hills, or driving off-road. 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 0 258. 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. The adaptive shift control process continually compares key shift parameters to pre-programmed ideal shifts stored in the transmission’s computer. The transmission constantly makes adjustments to improve vehicle performance according to how the vehicle is being used, such as with a heavy load or when the 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 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.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

M : This position allows selection of a range of gears appropriate for current driving conditions. If equipped, see “Range Selection Mode” under Manual Mode 0 288.

Caution

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.

Normal Mode Grade Braking If equipped with a gasoline engine and an automatic transmission, Normal Mode Grade Braking is enabled when the vehicle is started, but is not enabled in Range Selection Mode. It assists in maintaining desired vehicle speeds when driving on downhill grades by using the engine and transmission to slow the vehicle. The first time the system engages for each ignition key cycle, a DIC message will be displayed. See Transmission Messages 0 159.

Driving and Operating

287

To disable or enable Normal Mode Grade Braking within the current ignition key cycle, press and hold the Tow/Haul button for five seconds. When the button is released, the requested mode change is made. A DIC message displays. See Transmission Messages 0 159. For other forms of grade braking, see Tow/Haul Mode 0 290 and Cruise Control 0 304. Kickdown Mode The accelerator pedal provides an additional downshift after pressing through the kickdown feature. It requires extra pedal pressure near the end of its travel to engage.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

288

Driving and Operating

Manual Mode

Range Selection Mode

If equipped, Range Selection Mode helps control the vehicle's transmission and vehicle speed while driving downhill or towing a trailer by letting you select a desired range of gears. To use this feature: 1. Move the shift lever to

M (Manual Mode).

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

With an 8–speed automatic transmission, hold the plus/minus buttons on the shift lever to select the highest or lowest range available for the current vehicle speed. When the shift lever is moved from D (Drive) to M (Manual Mode), a number displays next to the M, indicating the current transmission range. This number is the highest gear that the transmission will command while operating in M (Manual Mode). All gears below that number are available. As driving conditions change, the transmission can automatically shift to lower gears. For example, when M5 is selected,

1 (First) through 5 (Fifth) gears are automatically shifted by the transmission, but 6 (Sixth) cannot be used until the plus/minus button on the shift lever is used to change to the range. In vehicles with gasoline engines, when the shift lever is moved from D (Drive) to M (Manual Mode), a downshift may occur. The gear that the transmission is operating in when the shift lever is moved from D (Drive) to M (Manual Mode) determines if a downshift occurs. See the following chart.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

6-Speed Automatic Transmission Gear before shifting from D (Drive) to M (Manual Mode) Range after shifting from D (Drive) to M (Manual Mode)

6th

5th

4th

3rd

2nd

1st

M4

M4

M3

M2

M2

M1

8th

7th

8-Speed Automatic Transmission Gear before shifting from D (Drive) to M (Manual Mode) Range after shifting from D (Drive) to M (Manual Mode) – Tow/Haul not engaged Range after shifting from D (Drive) to M (Manual Mode) – Tow/Haul engaged

6th

5th

4th

3rd

2nd

1st

M6 M6 M5 M4

M6 M5 M4 M3

M3

M3

M2

M1

M3

M3

M2

M1

Grade Braking is not available when Range Selection Mode is active. See Tow/Haul Mode 0 290. 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.

Driving and Operating

289

Caution

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 equipped, Low Traction Mode assists in vehicle acceleration when road conditions are slippery, such as with ice or snow. While the vehicle is at a stop, select M2 using Range Selection Mode. This will limit torque to the wheels and help to prevent the tires from spinning.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

290

Driving and Operating

Tow/Haul Mode

Vehicles with an automatic transmission have a Tow/Haul Mode. The Tow/Haul Mode adjusts the transmission shift pattern to reduce shift cycling. This provides increased performance, vehicle control, and enhanced transmission and engine cooling when driving down steep hills or mountain grades, towing, or hauling heavy loads.

The selector button is 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 cluster will come on. See Tow/Haul Mode Light 0 142 and Hill and Mountain Roads 0 264. Also see “Tow/Haul Mode” under Towing Equipment 0 338. Tow/Haul Mode Grade Braking Tow/Haul Mode Grade Braking is only enabled while the Tow/Haul Mode is selected and the vehicle is not in the Range Selection Mode. See “Tow/Haul Mode” listed previously and Manual Mode 0 288. Tow/Haul Mode Grade Braking assists in maintaining desired vehicle speeds when driving on downhill grades by using the engine and transmission to slow the vehicle.

On vehicles with a gasoline engine, to disable or enable Tow/Haul Grade Braking within the current ignition key cycle, press and hold the Tow/Haul button for five seconds. When the button is released, the requested mode change is made. A DIC message is displayed. See Transmission Messages 0 159. On vehicles with a diesel engine, Tow/Haul Mode Grade Braking can be enabled or disabled by pressing the Tow/Haul Mode button. Use the exhaust brake and Tow/Haul Mode for maximum grade braking. See Towing Equipment 0 338. For other forms of grade braking, see Automatic Transmission 0 284
and Cruise Control 0 304.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

Drive Systems

Four-Wheel Drive If equipped, four-wheel drive engages the front axle for extra traction. Read the appropriate section for transfer case operation before using.

Caution

Do not drive on clean, dry pavement in 4 m and 4 n (if equipped) for an extended period of time. These conditions may cause premature wear on the vehicle’s powertrain.

Driving on clean, dry pavement in four-wheel drive may: . Cause a vibration to be felt in

the steering system.

. Cause tires to wear faster. . Make the transfer case harder to shift, and cause it to run noisier.

Driving and Operating

291

{ Warning

Manual Transfer Case

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 0 300.

Caution

Extended high-speed operation in 4 n may damage or shorten the life of the drivetrain.

Engagement noise and bump when shifting between 4 n and 4 m or from N (Neutral), with the engine running, is normal. Shifting into 4 n will turn Traction Control and StabiliTrak® off. See Traction Control/Electronic Stability Control 0 301.

Move the lever to shift into and out of four-wheel drive.

An indicator light comes on when four-wheel drive is engaged. See Four-Wheel-Drive Light 0 142.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

292

Driving and Operating

N (Neutral) : Use only when the vehicle needs to be towed. See Recreational Vehicle Towing 0 436
or Towing the Vehicle 0 436. 2 m (Two-Wheel Drive High) : Use this setting for driving on most streets and highways. The front axle is not engaged. This setting provides the best fuel economy. 4 n (Four-Wheel Drive Low) : This setting also engages the front axle and delivers extra torque. Choose 4
n if driving off-road in deep sand, deep mud, or deep snow, and while climbing or descending steep hills. When engaged, keep vehicle speed below 72 km/h (45 mph). 4 m (Four-Wheel Drive High) : Use this setting when extra traction is needed. The front axle engages and helps when driving on snowy or icy roads, when off-roading, or when plowing snow.

The vehicle can be shifted between 2 m and 4 m while the vehicle is moving. In extremely cold weather, it may be necessary to stop or slow the vehicle to shift into 4 m. Using the Manual Transfer Case . Use quick motions to shift into or

out of 4 n or N (Neutral).

. Shifting may be harder when the vehicle is cold, but will return to normal once warmed up.

. Four-wheel drive reduces fuel

economy.

Shifting from 2 m to 4 m . Shifts can be made at any

vehicle speed.

. Shift in one continuous motion. . Shifting while the vehicle is in

motion may require that moderate force be applied to the shift lever before 4 m can be engaged, especially in cold weather.

In extremely cold weather, it may be necessary to slow or stop the vehicle to shift.

. While in 4 m, the vehicle can be driven at any posted legal speed limit.

Shifting In or Out of 4 n

Caution

Shifting the transfer case into 4 n 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.

1.

If possible, shift with the vehicle moving 5 km/h (3 mph) or less.

2. Shift the transmission into

N (Neutral).

3. Shift the transfer case shift

lever in one continuous motion.

4. Shifting with the vehicle at a

stop may be more difficult. It is possible that the shift will not

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

complete and the transfer case will remain in N (Neutral). This is normal. To complete the shift, with the engine running, shift the transmission to D (Drive) and back to N (Neutral), and reattempt the transfer case shift.

Shifting In or Out of Neutral 1. Have the engine running. 2. Set the parking brake. Press

and hold the brake pedal. See Parking Brake 0 300.

3. Place the transmission into

N (Neutral).

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

Electronic Transfer Case

Use the transfer case knob, next to the steering wheel, to shift into and out of four-wheel drive for extra traction. Indicator lights on the knob show which setting the transfer case is in. The N (Neutral) indicator is on the face of the knob. The indicator lights display briefly when the ignition is turned on, and one will stay on. If the lights display momentarily when the ignition is in ON/RUN, but none stay on, the knob may have been turned while the vehicle was off. To see the indicator, turn the

Driving and Operating

293

knob to another position so that it matches the actual transfer case setting. If no lights display, take the vehicle to your dealer for service. An indicator light flashes while shifting and until the shift is complete. If the transfer case cannot complete a requested shift, it will return to the last chosen setting. Turn the control back to the previous setting to see the indicator light.

Caution

Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case.

The settings are: N (Neutral) : Use only when the vehicle needs to be towed. See Recreational Vehicle Towing 0 436
or Towing the Vehicle 0 436.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

294

Driving and Operating

2 m (Two-Wheel Drive High) : Use for driving on most streets and highways. The front axle is not engaged. This setting provides the best fuel economy. 4 n (Four-Wheel Drive Low) : This setting engages the front axle and delivers extra torque. Choose 4 n if driving off-road in deep sand, deep mud, or deep snow, and while climbing or descending steep hills. When engaged, keep vehicle speed below 72 km/h (45 mph). Shifting into 4 n will turn Traction Control and StabiliTrak off. See Traction Control/Electronic Stability Control 0 301. 4 m (Four-Wheel Drive High) : Use when extra traction is needed. The front axle engages and helps when driving on snowy or icy roads, when off-roading, or when plowing snow. The vehicle can be shifted from 2 m to 4 m while the vehicle is moving.

Shifting Into 4 m Turn the knob to 4 m at any speed up to 121 km/h (75 mph), except from 4 n. The indicator light will flash while shifting and will remain on the selected setting. Shifting Into 2 m Turn the knob to 2 m at any speed, except when shifting from 4 n. Shifting Into 4 n When 4 n is engaged, vehicle speed should be kept below 72 km/h (45 mph). 1. 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). It is best for the vehicle to be moving 1.6 to 3.2 km/h (1 to 2 mph).

2. Turn the knob to 4 n. Wait for the 4 n indicator light to stop flashing before shifting the transmission into gear.

If the transmission is in gear and/or moving more than 5 km/h (3 mph), the 4 n indicator light will flash for 30 seconds and not complete the shift. After 30 seconds the transfer case will shift to 4 m. Turn the knob to 4 m to see the indicator. With the vehicle moving less than 5 km/h (3 mph), and the transmission in N (Neutral), attempt the shift again. Shifting Out of 4 n 1. To shift out of 4 n 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. It is best for the vehicle to be moving 1.6 to 3.2 km/h (1 to 2 mph).

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

2. Turn the knob to 4 m or 2 m.

Wait for the 4 m or 2 m indicator light to stop flashing before shifting the transmission into gear.

If the transmission is in gear and/or moving more than 5 km/h (3 mph), the 4 m or 2 m indicator light will flash for 30 seconds, but will not complete the shift. With the vehicle moving less than 5 km/h (3 mph), and the transmission in N (Neutral), attempt the shift again.

Shifting Into N (Neutral) To shift: 1. Park the vehicle on a level

surface.

2. Set the parking brake and press and hold the brake pedal. See Parking Brake 0 300.

3. Start the vehicle or turn the

ignition to ON/RUN.

4. Shift the transmission to

N (Neutral).

5. Shift the transfer case to 2 m.

6. Turn the transfer case knob

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 4 n position. The N (Neutral) light will come on when the transfer case shift to N (Neutral) is complete.

7. With the engine running, verify

that the transfer case is in N (Neutral) by shifting the transmission to R (Reverse), then to D (Drive). There should be no movement of the vehicle while shifting the transmission.

8. Turn the engine off, and the

ignition to ACC/ACCESSORY.

9. Place the transmission shift

lever in P (Park). See Recreational Vehicle Towing 0 436.

10. Turn the ignition to LOCK/OFF.

Driving and Operating

295

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

apply the brake pedal.

2. Turn the ignition to ON/RUN

with the engine off.

3. Shift the transmission to

N (Neutral).

4. Turn the transfer case knob to

2 m. After the transfer case has shifted out of N (Neutral), the N (Neutral) light will go out. 5. Release the parking brake.

Caution

Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case.

6. Start the engine and shift the

transmission to the desired gear.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

296

Driving and Operating

Automatic Transfer Case

Use the transfer case knob next to the steering wheel to shift into and out of four-wheel drive. Indicator lights display which setting the transfer case is in. N (Neutral) is indicated on the knob. The indicator lights will display briefly when the ignition is turned on and one will stay on. If the lights display momentarily when the ignition is in ON/RUN, but none stay on, the knob may have been turned while the vehicle was off. To see the indicator, turn the knob to another position so that it matches the

actual transfer case setting. If no lights display, 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 the transfer case cannot make a requested shift, it will return to the last chosen setting. Turn the knob back to the previous transfer case setting to see the indicator. The settings are: N (Neutral) : Use only when the vehicle needs to be towed. See Recreational Vehicle Towing 0 436
or Towing the Vehicle 0 436. 2 m (Two-Wheel Drive High) : Use for driving on most streets and highways. The front axle is not engaged. This setting provides the best fuel economy. AUTO (Automatic Four-Wheel Drive) : Use when road surface traction conditions are variable. When driving in AUTO, the front axle is engaged, and the vehicle's power is sent to the front and rear

wheels automatically based on driving conditions. This setting provides slightly lower fuel economy than 2 m. Do not use AUTO mode to park on a steep grade with poor traction such as ice, snow, mud, or gravel. In AUTO mode only the rear wheels will hold the vehicle from sliding when parked. If parking on a steep grade, use 4 m to keep all four wheels engaged. 4 m (Four-Wheel Drive High) : Use this position when extra traction is needed, such as when driving on snowy or icy roads, when off-roading, or when plowing snow. 4 n (Four-Wheel Drive Low) : This setting engages the front axle and delivers extra torque. Choose 4 n when driving off-road in deep sand, deep mud, or deep snow, and while climbing or descending steep hills. Shifting into 4 n will turn Traction Control and StabiliTrak off. See Traction Control/Electronic Stability Control 0 301.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

Shifting Into 4 m or AUTO Turn the knob to the 4 m or AUTO position at any speed, except from 4 n. The indicator light will flash while shifting and will remain on when the shift is completed. Shifting Into 2 m Turn the knob to 2 m at any speed, except when shifting from 4 n. The indicator light will flash while shifting and will remain on when the shift is completed. Shifting Into 4 n When 4 n is engaged, keep vehicle speed below 72 km/h (45 mph). To shift: 1. 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). It is best for the vehicle to be moving 1.6 to 3.2 km/h (1 to 2 mph).

2. Turn the knob to 4 n. Wait for the 4 n indicator light to stop flashing before shifting the transmission into gear.

Caution

Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case.

If the transmission is in gear and/or moving more than 5 km/h (3 mph), the 4 n indicator light will flash for 30 seconds and not complete the shift. After 30 seconds the transfer case will shift to 4 m. Turn the knob to 4 m to display the indicator. With the vehicle moving less than 5 km/h (3 mph), and the transmission in N (Neutral), attempt the shift again.

Driving and Operating

297

Shifting Out of 4 n To shift: 1. 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. It is best for the vehicle to be moving 1.6 to 3.2 km/h (1 to 2 mph). 2. Turn the knob to 4 m, AUTO,

or 2 m. Wait for the 4 m, AUTO, or 2 m indicator light to stop flashing before shifting the transmission into gear.

Caution

Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case.

If the transmission is in gear and/or moving more than 5 km/h (3 mph), the 4 m, AUTO, or 2 m indicator light will flash for 30 seconds but will not

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

298

Driving and Operating

complete the shift. With the vehicle moving less than 5 km/h (3 mph), and the transmission in N (Neutral), attempt the shift again.

Shifting Into N (Neutral) To shift into N (Neutral): 1. Park the vehicle on a level

surface.

2. Set the parking brake and press and hold the brake pedal. See Parking Brake 0 300.

3. Start the vehicle or turn the

ignition to ON/RUN.

4. Shift the transmission to

N (Neutral).

5. Shift the transfer case to 2 m. 6. Turn the transfer case knob

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 4 n position. The N (Neutral) light will come on when the transfer case shift to N (Neutral) is complete.

7. With the engine running, verify

that the transfer case is in N (Neutral) by shifting the transmission to R (Reverse), then shift the transmission to D (Drive). There should be no movement of the vehicle while shifting the transmission.

8. Turn the engine off, and the

ignition to ACC/ACCESSORY.

9. Place the transmission shift

lever in P (Park). See Recreational Vehicle Towing 0 436.

10. Turn the ignition to LOCK/OFF.

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

apply the brake pedal.

2. Turn the ignition to ON/RUN

with the engine off.

3. Shift the transmission to

N (Neutral).

4. Turn the transfer case knob to

the desired setting. After the transfer case has shifted out of N (Neutral), the N (Neutral) light will go out. 5. Release the parking brake. 6. Start the engine and shift the

transmission to the desired gear.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

Brakes

Antilock Brake System (ABS) This vehicle has ABS, an advanced electronic braking system that helps prevent a braking skid. When 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 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 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 you 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.

If there is a problem with ABS, this warning light stays on. See Antilock Brake System (ABS) Warning Light 0 142.

Driving and Operating

299

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 may hear the ABS pump or motor operating and feel the brake pedal pulsate. This is normal. Braking in Emergencies ABS allows you to steer and brake at the same time. In many emergencies, steering can help more than even the very best braking.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

300

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 0 141.

Caution

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 0 321.

Brake Assist The Brake Assist feature is 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.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

Hill Start Assist (HSA) This vehicle has an 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 you completely stop and hold the vehicle in a complete standstill on a grade, HSA will automatically activate. During the transition period between when you release the brake pedal and start 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 may activate. If you release the brake pedal and then reapply the brake pedal while HSA is activated, the brake pedal typically feels firmer with less pedal travel.

Driving and Operating

301

Ride Control Systems

Traction Control/ Electronic Stability Control

System Operation The vehicle has a Traction Control System (TCS) and StabiliTrak®, an electronic stability control system. These systems help limit wheel spin and assist the driver in maintaining control, especially on slippery road conditions. TCS activates if it senses any of the drive wheels are spinning or beginning to lose traction. When this happens, TCS applies the brakes to the spinning wheels and reduces engine power to limit wheel spin. StabiliTrak activates when the vehicle senses a difference between the intended path and the direction the vehicle is actually traveling. StabiliTrak selectively applies braking pressure to any one of the vehicle wheel brakes to assist the driver in keeping the vehicle on the

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

302

Driving and Operating

intended path. Trailer Sway Control (TSC) is also on automatically when the vehicle is started. See Trailer Sway Control (TSC) 0 347. If cruise control is being used and traction control or StabiliTrak begins to limit wheel spin, cruise control will disengage. Cruise control may be turned back on when road conditions allow. Both systems come on automatically when the vehicle is started and begins to move. The systems may be heard or felt while they are operating or while performing diagnostic checks. This is normal and does not mean there is a problem with the vehicle. It is recommended to leave both systems on for normal driving conditions, but it may be necessary to turn TCS off if the vehicle gets stuck in sand, mud, ice, or snow. See If the Vehicle Is Stuck 0 266
and “Turning the Systems Off and On” later in this section. When the transfer case (if equipped) is in Four-Wheel Drive Low, the stability system is automatically

disabled, g comes on, and the appropriate message will appear on the DIC. Both traction control and StabiliTrak are automatically disabled in this condition.

The indicator light for both systems is in the instrument cluster. This light will: . Flash when TCS is limiting

wheel spin.

. Flash when StabiliTrak is

activated.

. Turn on and stay on when either

system is not working.

If either system fails to turn on or to activate, a message displays in the Driver Information Center (DIC), and d comes on and stays on to indicate that the system is inactive and is not assisting the driver in

maintaining control. The vehicle is safe to drive, but driving should be adjusted accordingly. If d comes on and stays on: 1. Stop the vehicle. 2. Turn the engine off and wait

15 seconds.

3. Start the engine. Drive the vehicle. If d comes on and stays on, the vehicle may need more time to diagnose the problem. If the condition persists, see your dealer. Turning the Systems Off and On

The button for TCS and StabiliTrak is on the center stack.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

cluster, then release. The appropriate message will display in the DIC. See Ride Control System Messages 0 155. To turn TCS and StabiliTrak on again, press and release the g button. The traction off light i and the StabiliTrak OFF light g in the instrument cluster turn off. StabiliTrak will automatically turn on if the vehicle exceeds 56 km/h (35 mph). Traction control will remain off. The vehicle has a Trailer Sway Control (TSC) feature and a Hill Start Assist (HSA) feature. See Trailer Sway Control (TSC) 0 347 or Hill Start Assist (HSA) 0 301. Adding accessories can affect the vehicle performance. See Accessories and Modifications 0 354.

Caution

Do not repeatedly brake or accelerate heavily when TCS is off. The vehicle driveline could be damaged.

To turn off only TCS, press and release the g button. The traction off light i displays in the instrument cluster. The appropriate message will display in the DIC. See Ride Control System Messages 0 155. To turn TCS on again, press and release the g button. The traction off light i displayed in the instrument cluster will turn off. If TCS is limiting wheel spin when the g button is pressed, the system will not turn off until the wheels stop spinning. To turn off both TCS and StabiliTrak, press and hold the g button until the traction off light i and the StabiliTrak OFF light g come on and stay on in the instrument

Driving and Operating

303

Hill Descent Control (HDC) If equipped, HDC can be used when driving downhill. It sets and maintains vehicle speed while descending a very steep incline in a forward or reverse gear. The HDC switch is on the center stack, below the climate controls. Press 5 to enable or disable HDC. Vehicle speed must be below 50 km/h (31 mph).

The HDC light displays on the instrument cluster when enabled. HDC can maintain vehicle speeds between 3 and 22 km/h (2 and 14 mph) on an incline greater than or equal to a 10% grade. A blinking HDC light indicates the system is actively applying the brakes to maintain vehicle speed.

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

304

Driving and Operating

When HDC is activated, the initial HDC speed is set to the current driving speed. It can be increased or decreased by pressing the +RES or SET- steering wheel controls or by applying the accelerator or brake pedal. This adjusted speed becomes the new set speed. HDC will remain enabled between 22 and 60 km/h (14 and 37 mph); however vehicle speed cannot be set or maintained in this range. It will automatically disable if the vehicle speed is above 80 km/h (50 mph) or above 60 km/h (37 mph) for at least 30 seconds. 5
must be pressed again to re-enable HDC.

When enabled, if the vehicle is at a speed above 22 km/h (14 mph) and less than 60 km/h (37 mph), a DIC message will display. See Vehicle Speed Messages 0 161.

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 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).

{ Warning

Cruise control can be dangerous where you cannot drive safely at a steady speed. Do not use 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.

If equipped with an Allison or Hydra-Matic 6-speed automatic transmission, see “Tow/Haul Mode Grade Braking” under Tow/Haul Mode 0 290 for an explanation of

GMC Sierra Owner Manual 9234758) - 2016 - CRC - 7/31/15

(GMNA-Localizing-U.S./Canada/Mexico-

how cruise control interacts with the Range Selection Mode, Tow/Haul Mode, and Grade Braking systems. If the cruise control is being used and the Traction Control System (TCS) or StabiliTrak begins to limit wheel spin, the cruise control will automatically disengage. See Traction Control/Electronic Stability Control 0 301. If a collision alert occurs when cruise control is activated, cruise control is disengaged. See Forward Collision Alert (FCA) System 0 311. When road conditions allow you to safely use it again, cruise control can be turned back on. If the brakes are applied, the cruise control disengages.

Driving and Operating

305

SET− (Set/Coast) : Press briefly to set the speed and activate cruise control. If cruise control is already active, use to decrease vehicle speed. * (Cancel) : Press to disengage cruise control without erasing the set speed from memory.

Setting Cruise Control If 5 is on when not in use, SET− or +RES could get pressed and go into cruise when not desired. Keep 5