2012 GMC Sierra Owners Manual

turned off. This is possible since outside air always flows through the system as the vehicle is moving forward unless it is set to recirculation mode. See “Recirculation” later in this section. Press the + or − buttons to increase or decrease the cabin temperature. The driver side or passenger side temperature display shows the temperature setting increasing or decreasing. The passenger temperature setting can be set to match the driver temperature setting by pressing the PASS button and turning off the PASS indicator. When the passenger temperature setting is set different than the driver setting, the indicator on the PASS button illuminates and both the driver side and passenger side temperature displays are shown. When in defrost mode the passenger temperature setting cannot be changed.

Automatic Operation AUTO (Automatic): When automatic operation is active, the system controls the inside temperature, the air delivery, and the fan speed. Use the steps below to place the entire system in automatic mode: 1. Press the AUTO button.

When AUTO is selected, the display changes to show the current temperature(s) and AUTO is lit on the display. The current air delivery mode and fan speed are also displayed for about five seconds. When AUTO is selected, the air conditioning operation and air inlet are automatically controlled. The air conditioning compressor may run when the outside temperature is above freezing. The air inlet will normally be set to outside air. If it is hot outside, the air inlet may automatically switch to the recirculate mode to

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help quickly cool down the air inside the vehicle. The light on the button comes on in recirculation.

2. Set the driver and passenger

temperature. To find your comfort setting, start with a 23°C (74°F) temperature setting and allow about 20 minutes for the system to regulate. Use the driver or passenger temperature buttons to adjust the temperature setting as necessary. If a temperature setting of 15°C (60°F) is chosen, the system remains at the maximum cooling setting. If a temperature setting of 32°C (90°F) is chosen, the system remains at the maximum heat setting. Choosing either maximum setting will not cause the vehicle to heat or cool any faster.

Do not cover the solar sensor located on the top of the instrument panel near the windshield. This

sensor regulates air temperature based on sun load. For more information on the solar sensor, see “Sensors” later in this section. To avoid blowing cold air in cold weather, the system delays turning the fan on until warm air is available. The length of delay depends on the engine coolant temperature. Pressing the fan switch overrides this delay and changes the fan to a selected speed. Manual Operation D C (Fan Control): Press these buttons to increase or decrease the fan speed. Pressing either fan button while in automatic control places the fan under manual control. The fan setting remains displayed and the AUTO light turns off. The air delivery mode remains under automatic control.

Climate Controls

8-7

H G (Air Delivery Mode Control): Press these buttons to change the direction of the airflow in the vehicle. Repeatedly press either button until the desired mode appears on the display. Pressing either mode button while the system is off changes the air delivery mode without turning the system on. Pressing either mode button while in automatic control places the mode under manual control. The air delivery mode setting displays and the AUTO light turns off. The fan remains under automatic control. H (Vent): Air is directed to the instrument panel outlets. ) (Bi-Level): Air is divided between the instrument panel and floor outlets. Some air is directed toward the windshield and side window outlets.

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8-8

Climate Controls

6 (Floor): Air is directed to the floor outlets, with some to the windshield, side window outlets, and second row floor outlets. In this mode, the system automatically selects outside air. - (Defog): This mode clears the windows of fog or moisture. Air is directed to the windshield, floor outlets, and side window vents. In this mode, the system turns off recirculation and runs the air conditioning compressor unless the outside temperature is close to freezing. The recirculation mode cannot be selected while in the defrost mode. 0 (Defrost): This mode removes fog or frost from the windshield more quickly. Air is directed to the windshield and side window vents, with some directed to the floor vents. In this mode, the system automatically forces outside air into the vehicle and runs the air conditioning compressor unless the outside temperature is close to

freezing. The recirculation mode cannot be selected while in the defrost mode. The passenger temperature control cannot be activated while in defrost mode. If the PASS button is pressed, the button indicator flashes three times and will not work. If the passenger temperature buttons are adjusted, the driver temperature indicator changes. The passenger temperature will not be displayed. If vent, bi-level, or floor mode is selected again, the climate control system displays the previous temperature settings. Do not drive the vehicle until all windows are clear. # (Air Conditioning): Press to turn the air conditioning (A/C) compressor on and off. An indicator light comes on to show that the air conditioning is on. If this button is pressed when the air conditioning compressor is unavailable due to outside

conditions, the indicator flashes three times and then turns off. If the air conditioning is on and the outside temperature drops below a temperature which is too cool for air conditioning to be effective, the air conditioning light turns off to show that the air conditioning mode has been canceled. On hot days, open the windows long enough to let hot inside air escape. This helps to reduce the time it takes for the vehicle to cool down. It also helps the system to operate more efficiently. The air conditioning system removes moisture from the air, so a small amount of water might drip under the vehicle while idling or after turning off the engine. This is normal. @ (Recirculation): Press to turn the recirculation mode on. An indicator light comes on to show that recirculation is on.

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This mode recirculates and helps to quickly cool the air inside the vehicle. It can be used to help prevent outside air and odors from entering the vehicle. The recirculation mode cannot be used with floor, defog, or defrost modes. If recirculation is selected with one of those modes, the indicator light flashes three times and then turns off. The air conditioning compressor also comes on when this mode is activated. While in recirculation mode, the windows may fog when the weather is cold and damp. To clear the fog, select either the defog or defrost mode and increase the fan speed. The recirculation mode can be turned off by pressing the outside air button, or by turning off the ignition. ; (Outside Air): Press to turn the outside air mode on. An indicator light on the button comes on to show that outside is on. When selected, air from outside the

vehicle circulates throughout the vehicle. The recirculation mode cannot be used with the outside air mode. Rear Window Defogger The rear window defogger uses a warming grid to remove fog from the rear window. 1 (Rear Window Defogger): For vehicles with this feature, press to turn the defogger on or off. It automatically turns off several minutes after it has been activated. The defogger can also be turned off by turning the engine off. Do not drive the vehicle until all windows are clear. Notice: Do not use a razor blade or sharp object to clear the inside rear window. Do not adhere anything to the defogger grid lines in the rear glass. These actions may damage the rear defogger. Repairs would not be covered by your warranty.

Climate Controls

8-9

Heated Mirror: For vehicles with heated outside rearview mirrors, the mirrors heat to help clear fog or frost from the surface of the mirror when the rear window defog button is pressed. See Power Mirrors on page 2‑15. Sensors

The solar sensor, located in the defrost grille in the middle of the instrument panel, monitors the solar heat. Do not cover the solar sensor or the system will not work properly.

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8-10

Climate Controls

The interior temperature sensor, located in the headliner, measures the temperature of the air inside the vehicle.

There is also an exterior temperature sensor located behind the front grille. This sensor reads the outside air temperature and helps maintain the temperature inside the vehicle. Any cover on the front of the vehicle could cause a false reading in the displayed temperature. The climate control system uses the information from these sensors to maintain comfort settings by adjusting the outlet temperature, fan speed, and the air delivery mode. The system may also supply cooler air to the side of the vehicle facing the sun. The recirculation mode will also be used as needed to maintain cool outlet temperatures.

Air Vents Use the air outlets located in the center and on the side of the instrument panel to direct the airflow. Use the thumbwheels near the air outlets to open or close off the airflow.

Operation Tips . Clear away any ice, snow,

or leaves from air inlets at the base of the windshield that could block the flow of air into the vehicle.

. Keep the path under the front seats clear of objects to help circulate the air inside of the vehicle more effectively.

. Use of non‐GM approved hood deflectors can adversely affect the performance of the system. Check with your dealer before adding equipment to the outside of the vehicle.

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Driving and Operating

Driving Information

Distracted Driving . . . . . . . . . . . . . 9-2
Defensive Driving . . . . . . . . . . . . . 9-3
Drunk Driving . . . . . . . . . . . . . . . . . 9-3
Control of a Vehicle . . . . . . . . . . . 9-4
Braking . . . . . . . . . . . . . . . . . . . . . . . 9-4
Steering . . . . . . . . . . . . . . . . . . . . . . . 9-4
Off-Road Recovery . . . . . . . . . . . . 9-5
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road Driving . . . . . . . . . . . . . . 9-6
Driving on Wet Roads . . . . . . . . 9-11
Highway Hypnosis . . . . . . . . . . . 9-12
Hill and Mountain Roads . . . . . 9-12
Winter Driving . . . . . . . . . . . . . . . 9-13
If the Vehicle Is Stuck . . . . . . . . 9-15
Vehicle Load Limits . . . . . . . . . . 9-16
Truck-Camper Loading

Information . . . . . . . . . . . . . . . . . 9-23

Starting and Operating

New Vehicle Break-In . . . . . . . . 9-25
Adjustable Throttle and Brake

Pedal . . . . . . . . . . . . . . . . . . . . . . . 9-25
Ignition Positions . . . . . . . . . . . . 9-26

Starting the Engine . . . . . . . . . . 9-27
Fast Idle System . . . . . . . . . . . . . 9-29
Retained Accessory

Power (RAP) . . . . . . . . . . . . . . . 9-29
Engine Coolant Heater . . . . . . . 9-30
Shifting Into Park . . . . . . . . . . . . 9-30
Shifting out of Park . . . . . . . . . . 9-32
Parking over Things

That Burn . . . . . . . . . . . . . . . . . . 9-32
Active Fuel Management® . . . 9-32

Engine Exhaust

Engine Exhaust . . . . . . . . . . . . . . 9-33
Running the Vehicle While

Parked . . . . . . . . . . . . . . . . . . . . . 9-34

Automatic Transmission

Automatic Transmission . . . . . 9-35
Manual Mode . . . . . . . . . . . . . . . . 9-38
Tow/Haul Mode . . . . . . . . . . . . . . 9-39

Drive Systems

Four-Wheel Drive . . . . . . . . . . . . 9-40

Brakes

Antilock Brake

System (ABS) . . . . . . . . . . . . . . 9-53
Parking Brake . . . . . . . . . . . . . . . 9-54
Brake Assist . . . . . . . . . . . . . . . . . 9-54
Hill Start Assist (HSA) . . . . . . . 9-54

Driving and Operating

9-1

Ride Control Systems

StabiliTrak® System . . . . . . . . . 9-55
Locking Rear Axle . . . . . . . . . . . 9-58

Cruise Control

Cruise Control . . . . . . . . . . . . . . . 9-58

Object Detection Systems

Ultrasonic Parking Assist . . . . 9-61
Rear Vision

Camera (RVC) . . . . . . . . . . . . . 9-62

Fuel

Fuel . . . . . . . . . . . . . . . . . . . . . . . . . 9-68
Recommended Fuel . . . . . . . . . 9-68
Gasoline Specifications (U.S.

and Canada Only) . . . . . . . . . . 9-69

California Fuel

Requirements . . . . . . . . . . . . . . 9-69
Fuels in Foreign Countries . . . 9-69
Fuel Additives . . . . . . . . . . . . . . . 9-70
Fuel E85 (85% Ethanol) . . . . . 9-71
Filling the Tank . . . . . . . . . . . . . . 9-72
Filling a Portable Fuel

Container . . . . . . . . . . . . . . . . . . . 9-73

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9-2

Driving and Operating

Towing

General Towing

Information . . . . . . . . . . . . . . . . . 9-74

Driving Characteristics and

Towing Tips . . . . . . . . . . . . . . . . 9-74
Trailer Towing . . . . . . . . . . . . . . . . 9-78
Towing Equipment . . . . . . . . . . . 9-94
Trailer Sway

Control (TSC) . . . . . . . . . . . . . 9-105

Conversions and Add-Ons

Add-On Electrical

Equipment . . . . . . . . . . . . . . . . 9-105

Adding a Snow Plow or

Similar Equipment . . . . . . . . 9-106

Pickup Conversion to

Chassis Cab . . . . . . . . . . . . . . 9-109

Driving Information

Distracted Driving Distraction comes in many forms and can take your focus from the task of driving. Exercise good judgment and do not let other activities divert your attention away from the road. Many local governments have enacted laws regarding driver distraction. Become familiar with the local laws in your area. To avoid distracted driving, always keep your eyes on the road, hands on the wheel, and mind on the drive. . Do not use a phone in

demanding driving situations. Use a hands-free method to place or receive necessary phone calls.

. Watch the road. Do not

read, take notes, or look up information on phones or other electronic devices.

. Designate a front seat

passenger to handle potential distractions.

. Become familiar with vehicle

features before driving, such as programming favorite radio stations and adjusting climate control and seat settings. Program all trip information into any navigation device prior to driving.

. Wait until the vehicle is parked

to retrieve items that have fallen to the floor.

. Stop or park the vehicle to tend

to children.

. Keep pets in an appropriate

carrier or restraint.

. Avoid stressful conversations while driving, whether with a passenger or on a cell phone.

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{ WARNING

Taking your eyes off the road too long or too often could cause a crash resulting in injury or death. Focus your attention on driving.

Refer to the infotainment section for more information on using that system, including pairing and using a cell phone. If equipped, refer to the navigation manual for information on that system, including pairing and using a cell phone.

Defensive Driving Defensive driving means “always expect the unexpected.” The first step in driving defensively is to wear the safety belt. See Safety Belts on page 3‑12. . Assume that other road users

(pedestrians, bicyclists, and other drivers) are going to be careless and make mistakes. Anticipate what they might do and be ready.

. Allow enough following distance

between you and the driver in front of you. Focus on the task of driving.

Driving and Operating

9-3

Drunk Driving Death and injury associated with drinking and driving is a global tragedy.

{ WARNING Drinking and then driving is very dangerous. Your reflexes, perceptions, attentiveness, and judgment can be affected by even a small amount of alcohol. You can have a serious — or even fatal — collision if you drive after drinking. Do not drink and drive or ride with a driver who has been drinking. Ride home in a cab; or if you are with a group, designate a driver who will not drink.

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9-4

Driving and Operating

Control of a Vehicle Braking, steering, and accelerating are important factors in helping to control a vehicle while driving.

Braking Braking action involves perception time and reaction time. Deciding to push the brake pedal is perception time. Actually doing it is reaction time. Average driver reaction time is about three-quarters of a second. In that time, a vehicle moving at 100 km/h (60 mph) travels 20 m (66 ft), which could be a lot of distance in an emergency. Helpful braking tips to keep in mind include: . Keep enough distance between

you and the vehicle in front of you.

. Avoid needless heavy braking. . Keep pace with traffic.

If the engine ever stops while the vehicle is being driven, brake normally but do not pump the brakes. Doing so could make the pedal harder to push down. If the engine stops, there will be some power brake assist but it will be used when the brake is applied. Once the power assist is used up, it can take longer to stop and the brake pedal will be harder to push.

Steering

Hydraulic Power Steering Your vehicle has hydraulic power steering. It may require maintenance. See Power Steering Fluid Power Steering Fluid on page 10‑25. If power steering assist is lost because the engine stops or the power steering system is not functioning, the vehicle can be steered but may required increased effort. See your dealer if there is a problem.

If the vehicle is a hybrid, see the hybrid supplement for more information. Curve Tips

Take curves at a reasonable speed.

. Reduce speed before entering a

curve.

. Maintain a reasonable steady

speed through the curve

. Wait until the vehicle is out of the curve before accelerating gently into the straightaway.

Steering in Emergencies

There are some situations when steering around a problem may be more effective than braking.

. Holding both sides of the

steering wheel allows you to turn 180 degrees without removing a hand.

. Antilock Brake System (ABS) allows steering while braking.

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Off-Road Recovery

The vehicle's right wheels can drop off the edge of a road onto the shoulder while driving. Follow these tips: 1. Ease off the accelerator and then, if there is nothing in the way, steer the vehicle so that it straddles the edge of the pavement.

2. Turn the steering wheel about one-eighth of a turn, until the right front tire contacts the pavement edge.

3. Then turn the steering wheel to go straight down the roadway.

Loss of Control

Skidding There are three types of skids that correspond to the vehicle's three control systems: . Braking Skid — wheels are not

rolling.

. Steering or Cornering

Skid — too much speed or steering in a curve causes tires to slip and lose cornering force. . Acceleration Skid — too much

throttle causes the driving wheels to spin.

Driving and Operating

9-5

Defensive drivers avoid most skids by taking reasonable care suited to existing conditions, and by not overdriving those conditions. But skids are always possible. If the vehicle starts to slide, follow these suggestions: . Ease your foot off the

accelerator pedal and quickly steer the way you want the vehicle to go. The vehicle may straighten out. Be ready for a second skid if it occurs.

. Slow down and adjust your driving according to weather conditions. Stopping distance can be longer and vehicle control can be affected when traction is reduced by water, snow, ice, gravel, or other material on the road. Learn to recognize warning clues — such as enough water, ice, or packed snow on the road to make a mirrored surface — and slow down when you have any doubt.

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9-6

Driving and Operating

Try to avoid sudden steering, acceleration, or braking, including reducing vehicle speed by shifting to a lower gear. Any sudden changes could cause the tires to slide.

Remember: Antilock brakes help avoid only the braking skid.

Off-Road Driving Four-wheel-drive vehicles can be used for off-road driving. Vehicles without four-wheel drive and vehicles not equipped with All Terrain (AT) or On-Off Road (OOR) tires must not be driven off-road except on a level, solid surface. To contact the tire manufacturer for more information about the original equipment tires, see the Limited Warranty and Owner Assistance Information manual. Controlling the vehicle is the key to successful off-road driving. One of the best ways to control the vehicle is to control the speed.

{ WARNING

When driving off-road, bouncing and quick changes in direction can easily throw you out of position. This could cause you to lose control and crash. You and your passengers should always wear safety belts.

Before Driving Off-Road . Have all necessary maintenance

and service work completed. Fuel the vehicle, fill fluid levels, and check inflation pressure in all tires, including the spare, if equipped.

. Read all the information about

four-wheel-drive vehicles in this manual.

. Make sure all underbody

shields, if equipped, are properly attached.

. Know the local laws that apply to

off-road driving.

To gain more ground clearance if needed, it may be necessary to remove the front fascia lower air dam. Notice: Operating the vehicle for extended periods without the front fascia lower air dam installed can cause improper air flow to the engine. Re‐attach the front fascia air dam after off-road driving. Loading the Vehicle for Off-Road Driving

{ WARNING

. Unsecured cargo on the load floor can be tossed about when driving over rough terrain. You or your passengers can be struck by flying objects. Secure the cargo properly.

(Continued)

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Driving and Operating

9-7

WARNING (Continued)

. Keep cargo in the cargo area as far forward and as low as possible. The heaviest things should be on the floor, forward of the rear axle.

. Heavy loads on the roof raise the vehicle's center of gravity, making it more likely to roll over. You can be seriously or fatally injured if the vehicle rolls over. Put heavy loads inside the cargo area, not on the roof.

For more information about loading the vehicle, see Vehicle Load Limits and Tires. Environmental Concerns . Always use established trails,

roads, and areas that have been set aside for public off-road recreational driving and obey all posted regulations.

. Do not damage shrubs, flowers,

trees, or grasses or disturb wildlife.

. Do not park over things that

burn. See Parking Over Things that Burn..

Driving on Hills Driving safely on hills requires good judgment and an understanding of what the vehicle can and cannot do.

{ WARNING

If the vehicle has the two‐speed automatic transfer case, shifting the transfer case to N (Neutral) can cause your vehicle to roll even if the transmission is in P (Park) for an automatic transmission or any gear position for a manual transmission. This is because the N (Neutral) position on the transfer case overrides the transmission. You or someone else could be injured. If leaving

(Continued)

WARNING (Continued)

the vehicle, set the parking brake and shift the transmission to P (Park) for an automatic transmission or any gear position for a manual transmission. Shift the transfer case to any position but N (Neutral).

Before driving on a hill, assess the steepness, traction, and obstructions. If the terrain ahead cannot be seen, get out of the vehicle and walk the hill before driving further. When driving on hills: . Use a low gear and keep a firm

grip on the steering wheel.

. Maintain a slow speed. . When possible, drive straight up

or down the hill.

. Slow down when approaching

the top of the hill.

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9-8

Driving and Operating

. Use headlamps even during the

day to make the vehicle more visible.

{ WARNING

Driving to the top of a hill at high speed can cause an accident. There could be a drop-off, embankment, cliff, or even another vehicle. You could be seriously injured or killed. As you near the top of a hill, slow down and stay alert.

. Never go downhill forward or backward with either the transmission or transfer case in N (Neutral). The brakes could overheat and you could lose control.

{ WARNING

{ WARNING

If the vehicle has the two‐speed automatic transfer case, shifting the transfer case to N (Neutral) can cause your vehicle to roll even if the transmission is in P (Park). This is because the N (Neutral) position on the transfer case overrides the transmission. You or someone else could be injured. If leaving the vehicle, set the parking brake and shift the transmission to P (Park). Shift the transfer case to any position but N (Neutral).

. When driving down a hill, keep

the vehicle headed straight down. Use a low gear because the engine will work with the brakes to slow the vehicle and help keep the vehicle under control.

Heavy braking when going down a hill can cause your brakes to overheat and fade. This could cause loss of control and you or others could be injured or killed. Apply the brakes lightly when descending a hill and use a low gear to keep vehicle speed under control.

If the vehicle stalls on a hill: 1. Apply the brakes to stop the vehicle, and then apply the parking brake.

2. Shift into P (Park) for an automatic transmission or 1 (First) for a manual transmission and then restart the engine.

If driving uphill when the vehicle stalls, shift to R (Reverse), release the parking brake, and back straight down.

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Never try to turn the vehicle around. If the hill is steep enough to stall the vehicle, it is steep enough to cause it to roll over. If you cannot make it up the hill, back straight down the hill. Never back down a hill in N (Neutral) using only the brake. The vehicle can roll backward quickly and you could lose control. If driving downhill when the vehicle stalls, shift to a lower gear, release the parking brake, and drive straight down the hill.

3.

If the vehicle cannot be restarted after stalling, set the parking brake, shift an automatic transmission into P (Park) or a manual transmission into 1 (First), and turn the vehicle off. 3.1. Leave the vehicle and

seek help.

3.2. Stay clear of the path the

vehicle would take if it rolled downhill.

. Avoid turns that take the vehicle

across the incline of the hill. A hill that can be driven straight up or down might be too steep to drive across. Driving across an incline puts more weight on the downhill wheels which could cause a downhill slide or a rollover.

. Surface conditions can be a

problem. Loose gravel, muddy spots, or even wet grass can cause the tires to slip sideways, downhill. If the vehicle slips

Driving and Operating

9-9

sideways, it can hit something that will trip it – a rock, a rut, etc. – and roll over.

. Hidden obstacles can make the

steepness of the incline more severe. If a rock is driven across with the uphill wheels, or if the downhill wheels drop into a rut or depression, the vehicle can tilt even more. If an incline must be driven across, and the vehicle starts to slide, turn downhill. This should help straighten out the vehicle and prevent the side slipping.

{ WARNING

Getting out of the vehicle on the downhill side when stopped across an incline is dangerous. If the vehicle rolls over, you could be crushed or killed. Always get out on the uphill side of the vehicle and stay well clear of the rollover path.

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9-10

Driving and Operating

Driving in Mud, Sand, Snow, or Ice Use a low gear when driving in mud – the deeper the mud, the lower the gear. Keep the vehicle moving to avoid getting stuck. Traction changes when driving on sand. On loose sand, such as on beaches or sand dunes, the tires tend to sink into the sand. This affects steering, accelerating, and braking. Drive at a reduced speed and avoid sharp turns or abrupt maneuvers. Traction is reduced on hard packed snow and ice and it is easy to lose control. Reduce vehicle speed when driving on hard packed snow and ice.

{ WARNING

Driving on frozen lakes, ponds, or rivers can be dangerous. Ice conditions vary greatly and the vehicle could fall through the ice; you and your passengers could drown. Drive your vehicle on safe surfaces only.

Driving in Water

{ WARNING

Driving through rushing water can be dangerous. Deep water can sweep your vehicle downstream and you and your passengers could drown. If it is only shallow water, it can still wash away the ground from under your tires. Traction could be lost, and the vehicle could roll over. Do not drive through rushing water.

Notice: Do not drive through standing water if it is deep enough to cover the wheel hubs, axles or exhaust pipe. Deep water can damage the axle and other vehicle parts. If the standing water is not too deep, drive slowly through it. At faster speeds, water splashes on the ignition system and the vehicle can stall. Stalling can also occur if you get the exhaust pipe under water. While the exhaust pipe is under water, you will not be able to start the engine. When going through water, the brakes get wet, and it might take longer to stop. See Driving on Wet Roads. After Off-Road Driving Remove any brush or debris that has collected on the underbody or chassis, or under the hood. These accumulations can be a fire hazard.

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After operation in mud or sand, have the brake linings cleaned and checked. These substances can cause glazing and uneven braking. Check the body structure, steering, suspension, wheels, tires, and exhaust system for damage and check the fuel lines and cooling system for any leakage. More frequent maintenance service is required. Refer to the Maintenance Schedule for more information.

Driving on Wet Roads Rain and wet roads can reduce vehicle traction and affect your ability to stop and accelerate. Always drive slower in these types of driving conditions and avoid driving through large puddles and deep‐standing or flowing water.

{ WARNING

Wet brakes can cause crashes. They might not work as well in a quick stop and could cause pulling to one side. You could lose control of the vehicle. After driving through a large puddle of water or a car/vehicle wash, lightly apply the brake pedal until the brakes work normally. Flowing or rushing water creates strong forces. Driving through flowing water could cause the vehicle to be carried away. If this happens, you and other vehicle occupants could drown. Do not ignore police warnings and be very cautious about trying to drive through flowing water.

Driving and Operating

9-11

Hydroplaning Hydroplaning is dangerous. Water can build up under the vehicle's tires so they actually ride on the water. This can happen if the road is wet enough and you are going fast enough. When the vehicle is hydroplaning, it has little or no contact with the road. There is no hard and fast rule about hydroplaning. The best advice is to slow down when the road is wet. Other Rainy Weather Tips Besides slowing down, other wet weather driving tips include: . Allow extra following distance. . Pass with caution. . Keep windshield wiping

equipment in good shape.

. Keep the windshield washer fluid

reservoir filled.

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9-12

Driving and Operating

Hill and Mountain Roads Driving on steep hills or through mountains is different than driving on flat or rolling terrain. Tips for driving in these conditions include: . Keep the vehicle serviced and in

good shape.

. Check all fluid levels and brakes,

tires, cooling system, and transmission.

. Shift to a lower gear when going

down steep or long hills.

. Have good tires with proper

tread depth. See Tires on page 10‑50. Turn off cruise control.

Highway Hypnosis Always be alert and pay attention to your surroundings while driving. If you become tired or sleepy, find a safe place to park the vehicle and rest. Other driving tips include: . Keep the vehicle well ventilated. . Keep the interior temperature cool.

. Keep your eyes moving — scan the road ahead and to the sides.

. Check the rearview mirror and

vehicle instruments often.

{ WARNING

If you do not shift down, the brakes could get so hot that they would not work well. You would then have poor braking or even none going down a hill. You could crash. Shift down to let the engine assist the brakes on a steep downhill slope.

{ WARNING

Coasting downhill in N (Neutral) or with the ignition off is dangerous. The brakes will have to do all the work of slowing down and they could get so hot that they would not work well. You would then have poor braking or even none going down a hill. You could crash. Always have the engine running and the vehicle in gear when going downhill.

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. Stay in your own lane. Do not swing wide or cut across the center of the road. Drive at speeds that let you stay in your own lane.

. Be alert on top of hills;

something could be in your lane (stalled car, accident).

. Pay attention to special road

signs (falling rocks area, winding roads, long grades, passing or no-passing zones) and take appropriate action.

Winter Driving

Driving on Snow or Ice Drive carefully when there is snow or ice between the tires and the road, creating less traction or grip. Wet ice can occur at about 0°C (32°F) when freezing rain begins to fall, resulting in even less traction. Avoid driving on wet ice or in freezing rain until roads can be treated with salt or sand. Drive with caution, whatever the condition. Accelerate gently so traction is not lost. Accelerating too quickly causes the wheels to spin and makes the surface under the tires slick, so there is even less traction.

Driving and Operating

9-13

Try not to break the fragile traction. If you accelerate too fast, the drive wheels will spin and polish the surface under the tires even more. The Antilock Brake System (ABS) on page 9‑53 improves vehicle stability during hard stops on slippery roads, but apply the brakes sooner than when on dry pavement. Allow greater following distance on any slippery road and watch for slippery spots. Icy patches can occur on otherwise clear roads in shaded areas. The surface of a curve or an overpass can remain icy when the surrounding roads are clear. Avoid sudden steering maneuvers and braking while on ice. Turn off cruise control on slippery surfaces.

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9-14

Driving and Operating

Blizzard Conditions Being stuck in snow can be a serious situation. Stay with the vehicle unless there is help nearby. If possible, use the Roadside Assistance Program (U.S. and Canada) on page 13‑7 or Roadside Assistance Program (Mexico) on page 13‑9. To get help and keep everyone in the vehicle safe:

Turn on the hazard warning flashers. Tie a red cloth to an outside mirror.

{ WARNING

Snow can trap engine exhaust under the vehicle. This may cause exhaust gases to get inside. Engine exhaust contains carbon monoxide (CO) which cannot be seen or smelled. It can cause unconsciousness and even death.

WARNING (Continued)

WARNING (Continued)

For more information about carbon monoxide, see Engine Exhaust on page 9‑33.

Run the engine for short periods only as needed to keep warm, but be careful. To save fuel, run the engine for only short periods as needed to warm the vehicle and then shut the engine off and close the window most of the way to save heat. Repeat this until help arrives but only when you feel really uncomfortable from the cold. Moving about to keep warm also helps.

If the vehicle is stuck in the snow: . Clear away snow from around

the base of your vehicle, especially any that is blocking the exhaust pipe.

. Check again from time to

time to be sure snow does not collect there.

. Open a window about 5 cm

(2 in) on the side of the vehicle that is away from the wind to bring in fresh air.

. Fully open the air outlets on

or under the instrument panel.

. Adjust the climate control

system to a setting that circulates the air inside the vehicle and set the fan speed to the highest setting. See “Climate Control Systems” in the Index.

(Continued)

(Continued)

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Driving and Operating

9-15

{ WARNING

If the vehicle's tires spin at high speed, they can explode, and you or others could be injured. The vehicle can overheat, causing an engine compartment fire or other damage. Spin the wheels as little as possible and avoid going above 56 km/h (35 mph).

For information about using tire chains on the vehicle, see Tire Chains on page 10‑74. Rocking Your Vehicle to Get It Out Turn the steering wheel left and right to clear the area around the front wheels. For four-wheel-drive vehicles, shift into Four‐Wheel High.

For vehicles with StabiliTrak®, turn the traction control part of the system off. Shift back and forth between R (Reverse) and a forward gear, spinning the wheels as little as possible. To prevent transmission wear, wait until the wheels stop spinning before shifting gears. Release the accelerator pedal while shifting, and press lightly on the accelerator pedal when the transmission is in gear. Slowly spinning the wheels in the forward and reverse directions causes a rocking motion that could free the vehicle. If that does not get the vehicle out after a few tries, it might need to be towed out. Recovery hooks can be used, if the vehicle has them. If the vehicle does need to be towed out, see Towing the Vehicle on page 10‑93.

If it takes some time for help to arrive, now and then when you run the engine, push the accelerator pedal slightly so the engine runs faster than the idle speed. This keeps the battery charged to restart the vehicle and to signal for help with the headlamps. Do this as little as possible to save fuel.

If the Vehicle Is Stuck Slowly and cautiously spin the wheels to free the vehicle when stuck in sand, mud, ice, or snow. See “Rocking Your Vehicle to Get It Out” later in this section. If the vehicle has a traction system, it can often help to free a stuck vehicle. Refer to the vehicle's traction system in the Index. If stuck too severely for the traction system to free the vehicle, turn the traction system off and use the rocking method.

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9-16

Driving and Operating

Recovery Hooks

{ WARNING

Never pull on recovery hooks from the side. The hooks could break and you and others could be injured. When using recovery hooks, always pull the vehicle straight out.

Notice: Never use recovery hooks to tow the vehicle. Your vehicle could be damaged and it would not be covered by warranty. For vehicles with recovery hooks at the front of the vehicle, you can use them if you are stuck off-road and need to be pulled to some place where you can continue driving.

Vehicle Load Limits It is very important to know how much weight your vehicle can carry. This weight is called the vehicle capacity weight and includes the weight of all occupants, cargo, and all nonfactory-installed options. Two labels on your vehicle show how much weight it was designed to carry, the Tire and Loading Information label and the Certification/Tire label.

{ WARNING

Do not load the vehicle any heavier than the Gross Vehicle Weight Rating (GVWR), or either the maximum front or rear Gross Axle Weight Rating (GAWR). This can cause systems to break and change the way the (Continued)

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Driving and Operating

9-17

the front and rear axles. See “Certification/Tire Label” later in this section.

Steps for Determining Correct Load Limit 1. Locate the statement

“The combined weight of occupants and cargo should never exceed XXX kg or XXX lbs” on your vehicle's placard.

2. Determine the combined weight of the driver and passengers that will be riding in your vehicle.

3. Subtract the combined weight of the driver and passengers from XXX kg or XXX lbs.

open, you will find the label attached below the door lock post (striker). The tire and loading information label shows the number of occupant seating positions (A), and the maximum vehicle capacity weight (B) in kilograms and pounds. The Tire and Loading Information label also shows the size of the original equipment tires (C) and the recommended cold tire inflation pressures (D). For more information on tires and inflation see Tires on page 10‑50 and Tire Pressure on page 10‑58. There is also important loading information on the vehicle Certification/Tire label. It tells you the Gross Vehicle Weight Rating (GVWR) and the Gross Axle Weight Rating (GAWR) for

WARNING (Continued)

vehicle handles. This could cause loss of control and a crash. Overloading can also shorten the life of the vehicle.

Tire and Loading Information Label

Label Example

A vehicle specific Tire and Loading Information label is attached to the center pillar (B-pillar). With the driver door

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9-18

Driving and Operating

4. The resulting figure equals

the available amount of cargo and luggage load capacity. For example, if the “XXX” amount equals 1400 lbs and there will be five 150 lb passengers in your vehicle, the amount of available cargo and luggage load capacity is 650 lbs (1400−750 (5x150) = 650 lbs).

your vehicle. See Trailer Towing on page 9‑78 for important information on towing a trailer, towing safety rules and trailering tips.

5. Determine the combined

weight of luggage and cargo being loaded on the vehicle. That weight may not safely exceed the available cargo and luggage load capacity calculated in Step 4. If your vehicle will be towing a trailer, the load from your trailer will be transferred to your vehicle. Consult this manual to determine how this reduces the available cargo and luggage load capacity of

6.

Example 2

A. Vehicle Capacity Weight for

Example 2 = 453 kg (1,000 lbs)

B. Subtract Occupant Weight @

68 kg (150 lbs) × 5 = 340 kg (750 lbs)

Example 1

A. Vehicle Capacity Weight for

C. Available Cargo Weight =

Example 1 = (453 kg) (1,000 lbs)

113 kg (250 lbs)

B. Subtract Occupant Weight @

68 kg (150 lbs) × 2 = 136 kg (300 lbs)

C. Available Occupant and Cargo

Weight = 317 kg (700 lbs)

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weight of the driver, passengers, and cargo should never exceed your vehicle's capacity weight.

Certification/Tire Label

Example 3

A. Vehicle Capacity Weight for

Example 3 = 453 kg (1,000 lbs)

B. Subtract Occupant Weight @

91 kg (200 lbs) × 5 = 453 kg (1,000 lbs)

C. Available Cargo Weight =

0 kg (0 lbs)

Refer to your vehicle's tire and loading information label for specific information about your vehicle's capacity weight and seating positions. The combined

A vehicle specific Certification/ Tire label is found on the rear edge of the driver door. The label shows the size of your vehicle's original tires and the inflation pressures needed to obtain the gross weight capacity of your vehicle.

Driving and Operating

9-19

This is called Gross Vehicle Weight Rating (GVWR). The GVWR includes the weight of the vehicle, all occupants, fuel, and cargo. The Certification/Tire label also tells you the maximum weights for the front and rear axles, called Gross Axle Weight Rating (GAWR). To find out the actual loads on your front and rear axles, you need to go to a weigh station and weigh your vehicle. Your dealer can help you with this. Be sure to spread out your load equally on both sides of the centerline. Never exceed the GVWR for your vehicle, or the GAWR for either the front or rear axle.

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9-20

Driving and Operating

The Certification/Tire label also contains important information about your Front Axle Reserve Capacity. See “What is front axle reserve capacity, and how do I calculate it?” under Adding a Snow Plow or Similar Equipment on page 9‑106.

{ WARNING

In the case of a sudden stop or collision, things carried in the bed of your truck could shift forward and come into the passenger area, injuring you and others. If you put things in the bed of your truck, you should make sure they are properly secured.

{ WARNING

Do not load the vehicle any heavier than the Gross Vehicle Weight Rating (GVWR), or either the maximum front or rear Gross Axle Weight Rating (GAWR). This can cause systems to break and change the way the vehicle handles. This could cause loss of control and a crash. Overloading can also shorten the life of the vehicle.

Notice: Overloading the vehicle may cause damage. Repairs would not be covered by the vehicle warranty. Do not overload the vehicle.

Using heavier suspension components to get added durability might not change your weight ratings. Ask your dealer to help you load your vehicle the right way. If you put things inside your vehicle — like suitcases, tools, packages, or anything else — they go as fast as the vehicle goes. If you have to stop or turn quickly, or if there is a crash, they will keep going.

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There is also important loading information for off-road driving in this manual. See “Loading Your Vehicle for Off-Road Driving“under Off-Road Driving on page 9‑6.

Two-Tiered Loading Depending on the model of your pick‐up, an upper load platform can be created by positioning three or four 5 cm (2 inches) by 15 cm (6 inches) wooden planks across the width of the pickup box. The planks must be inserted in the pickup box depressions.

Driving and Operating

9-21

When using this upper load platform, be sure the load is securely tied down to prevent it from shifting. The load's center of gravity should be positioned in a zone over the rear axle. The zone is located in the area between the front of each wheel well and the rear of each wheel well. The center of gravity height must not extend above the top of the pickup box flareboard. Any load that extends beyond the vehicle's taillamp area must be properly marked according to local laws and regulations. Remember not to exceed the Gross Axle Weight Rating (GAWR) of the front or rear axle.

{ WARNING

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

. Put things in the cargo

area of the vehicle. Try to spread the weight evenly.

. Never stack heavier

things, like suitcases, inside the vehicle so that some of them are above the tops of the seats.

. Do not leave an

unsecured child restraint in the vehicle.

. When you carry something

inside the vehicle, secure it whenever you can.

. Do not leave a seat folded down unless you need to.

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Driving and Operating

Add-On Equipment When you carry removable items, you may need to put a limit on how many people you carry inside your vehicle. Be sure to weigh your vehicle before you buy and install the new equipment. Notice: Overloading the vehicle may cause damage. Repairs would not be covered by the vehicle warranty. Do not overload the vehicle. Remember not to exceed the Gross Axle Weight Rating (GAWR) of the front or rear axle.

* Equipment Ladder Rack and Cargo Cross Toolbox and Cargo Side Boxes and Cargo

Maximum Weight 340 kg (750 lbs) 181 kg (400 lbs) 113 kg per side (250 lbs per side)

* The combined weight for all rail‐mounted equipment should not exceed 454 kg (1,000 lbs).

Loading Points

A. Primary Load Points B. Secondary Load Areas C. Cargo Management Option

Holes

Structural members (A) and (B) are included in the pick-up box design. Additional accessories should use these load points. Depending on the accessory design, use a spacer under the accessory at the load points to remove gap.

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Driving and Operating

9-23

The holes for the Cargo Management System (C) are not intended for attachment of aftermarket equipment. See www.gmupfitter.com for additional pick-up box load bearing structural information.

Truck-Camper Loading Information A vehicle-specific Truck‐Camper Loading Information label is attached to the inside of the vehicle's glove box. This label indicates if a slide-in camper can be carried, how much of a load the vehicle can carry, and how to correctly spread out the load. It will help to match the right slide in camper to the vehicle. Your dealer can help make a good vehicle-camper match and help determine the Cargo Weight Rating (CWR).

When installing and loading a slide-in camper, check the manufacturer's instructions. When carrying a slide-in camper, the total cargo load of the vehicle is the weight of the camper, plus the following: . Everything added to the

camper after it left the factory

. Everything in the camper . All the people inside The CWR is the maximum weight of the load the vehicle can carry. It does not include the weight of the people inside. But, use about 68 kg (150 lbs) for each seat. The total cargo load must not be more than the vehicle's CWR.

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

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

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Driving and Operating

Here is an example of proper truck and camper match:

A. Camper Center of Gravity B. Recommended Center of

Gravity Location Zone

When the truck is used to carry a slide‐in camper, the total cargo load of the truck consists of the manufacturer's camper weight figure, the weight of installed additional camper equipment not included in the manufacturer's camper weight figure, the weight

of camper cargo, and the weight of passengers in the camper. The total cargo load should not exceed the truck's cargo weight rating, and the camper's center of gravity (A) should fall within the truck's recommended center of gravity zone (B) when installed. Any accessories or other equipment that are added to the vehicle must be weighed. Then, subtract this extra weight from the CWR. This extra weight may shorten the center of gravity zone of the vehicle. If the slide-in camper and its load weighs less than the CWR, the center of gravity zone for your vehicle may be larger. Secure loose items to prevent weight shifts that could affect the balance of the vehicle. When the truck‐camper is loaded, drive to a scale and weigh on the front

and on the rear wheels separately to determine axle loads. Individual axle loads should not exceed either of the gross axle weight ratings (GAWR). The total axle loads should not exceed your vehicle's gross vehicle weight rating (GVWR). These ratings are given on the vehicle certification label attached to the rear edge of the driver door. See “Certification/Tire Label” under Vehicle Load Limits on page 9‑16. If weight ratings are exceeded, move or remove items to bring all weights below the ratings. See your dealer for more information on curb weights, cargo weights, Cargo Weight Rating and the correct center of gravity zone.

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Starting and Operating

New Vehicle Break-In Notice: The vehicle does not need an elaborate break-in. But it will perform better in the long run if you follow these guidelines: . Keep the vehicle speed at

88 km/h (55 mph) or less for the first 805 km (500 miles).

. Do not drive at any one constant speed, fast or slow, for the first 805 km (500 miles). Do not make full-throttle starts. Avoid downshifting to brake or slow the vehicle.

. Avoid making hard stops for the first 322 km (200 miles) or so. During this time the new brake linings are not yet broken in. Hard stops with new linings can mean premature wear and earlier

replacement. Follow this breaking-in guideline every time you get new brake linings.

. Do not tow a trailer during

break-in. See Trailer Towing on page 9‑78 for the trailer towing capabilities of the vehicle and more information.

Following break‐in, engine speed and load can be gradually increased.

Adjustable Throttle and Brake Pedal On vehicles with this feature, you can change the position of the throttle and brake pedals. No adjustment to the pedals can be made when the vehicle is in R (Reverse) or while using cruise control.

Driving and Operating

9-25

The control used to adjust the pedals is located on the instrument panel below the climate control system. Press the bottom of the control to move the pedals closer. Press the top of the control to move the pedals away. Before you start driving, fully press the brake pedal to confirm the adjustment is right for you. While driving, make only small adjustments. The vehicle may have a memory function which lets pedal settings be saved and recalled. See Memory Seats on page 3‑7.

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Driving and Operating

Ignition Positions

The ignition switch has four different positions. To shift out of P (Park), the ignition must be in ON/RUN or ACC/ ACCESSORY and the regular brake pedal must be applied. A (STOPPING THE ENGINE/ LOCK/OFF): When the vehicle is stopped, turn the ignition switch to LOCK/OFF to turn the engine off. Retained Accessory Power (RAP)

will remain active. See Retained Accessory Power (RAP) on page 9‑29. This position locks the ignition. It also locks the transmission on automatic transmission vehicles. The key can be removed in LOCK/OFF. Do not turn the engine off when the vehicle is moving. This will cause a loss of power assist in the brake and steering systems and disable the airbags. If the vehicle must be shut off in an emergency: 1. Brake using a firm and steady

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 on page 9‑54.

{ 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.

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The steering can bind with the wheels turned off center. If this happens, move the steering wheel from right to left while turning the key to ACC/ACCESSORY. If this does not work, then the vehicle needs service. Notice: 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. B (ACC/ACCESSORY): This position lets things like the radio and the windshield wipers operate while the engine is off. Use this position if the vehicle must be pushed or towed. C (ON/RUN): This position can be used to operate the electrical accessories and to display some