2014 GMC Sierra Owners Manual

is used to turn on or off the Front and Rear Parking Assist. The indicator light in the button comes on when the features are on and turns off when the features have been disabled. Front and Rear Parking Assist can be turned off, on, or on with towbar through vehicle personalization. See “Parking Assist” under Vehicle Personalization on page 5-45. If the parking assist is turned off through vehicle personalization, the park

assist button on the center stack will be disabled. To turn the parking assist on again, select On in the vehicle personalization menu. The On with Towbar setting allows for the parking assist to work properly with a small item attached to the trailer hitch. Turn off parking assist when towing a trailer. To turn the Rear Vision Camera (RVC) system rear parking assist symbols or guidance lines on or off: 1. On the infotainment system

Home screen, press the Settings screen button, or turn the MENU knob to highlight Settings and press MENU.

2. Select Rear Camera. 3. Press Rear Park Assist Symbols

or Guidance Lines and then select Off or On.

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Driving and Operating

Disconnecting the Rear Vision Camera (RVC) The RVC must be disconnected if the tailgate needs to be removed. The RVC is disconnected by removing the connector from the electrical junction block mounted on the left side of the cross member of the vehicle frame. After disconnecting, the cap mounted next to the camera connector must be relocated so that the open terminals on the junction block are covered.

Assistance Systems for Driving If equipped, when driving the vehicle, Forward Collision Alert (FCA) and Lane Departure Warning (LDW) can help to avoid a crash or reduce crash damage.

Forward Collision Alert (FCA) System If equipped, the FCA system may help to avoid or reduce the harm caused by front-end crashes. When approaching a vehicle ahead too quickly, FCA provides a red flashing alert on the windshield and rapidly beeps or pulses the driver seat. FCA also lights an amber visual alert if following another vehicle much too closely. FCA detects vehicles within a distance of approximately 60 m (197 ft) and operates at speeds above 40 km/h (25 mph). { Warning

FCA is a warning system and does not apply the brakes. When approaching a slower-moving or stopped vehicle ahead too rapidly, or when following a vehicle too closely, FCA may not provide a

(Continued)

Warning (Continued)

warning with enough time to help avoid a crash. FCA does not warn of pedestrians, animals, signs, guardrails, bridges, construction barrels, or other objects. Be ready to take action and apply the brakes. For more information, see Defensive Driving on page 9-3.

FCA can be disabled with the FCA steering wheel control. Detecting the Vehicle Ahead

FCA warnings will not occur unless the FCA system detects a vehicle ahead. When a vehicle is detected ahead, the vehicle ahead indicator will display green. Vehicles may not

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be detected on curves, highway exit ramps, or hills; or due to poor visibility. FCA will not detect another vehicle ahead until it is completely in the driving lane.

{ Warning

FCA does not provide a warning to help avoid a crash, unless it detects a vehicle. FCA may not detect a vehicle ahead if the FCA sensor is blocked by dirt, snow, or ice, or if the windshield is damaged. It may also not detect a vehicle on winding or hilly roads, or in conditions that can limit visibility such as fog, rain, or snow, or if the headlamps or windshield are not cleaned or in proper condition. Keep the windshield, headlamps, and FCA sensors clean and in good repair.

Collision Alert

Driving and Operating

9-65

as needed. Cruise control may be disengaged when the Collision Alert occurs.

Tailgating Alert

The vehicle ahead indicator will display amber when you are following a vehicle ahead much too closely.

When your vehicle approaches another detected vehicle too rapidly, six red lights will flash on the windshield. Also, eight rapid high-pitched beeps will sound from the front, or both sides of the Safety Alert Seat will pulse five times. When this Collision Alert occurs, the brake system may prepare for driver braking to occur more rapidly which can cause a brief, mild deceleration. Continue to apply the brake pedal

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Driving and Operating

Selecting the Alert Timing

The FCA control I son the steering wheel. Press [ to set the FCA timing to Far, Medium, Near, or Off. The first button press shows the current setting on the DIC. Additional button presses will change this setting. The chosen setting will remain until it is changed and will affect the timing of both the Collision Alert and the Tailgating Alert features. The timing of both alerts will vary based on vehicle speed. The faster the vehicle speed, the farther away the alert will occur.

Consider traffic and weather conditions when selecting the alert timing. The range of selectable alert timing may not be appropriate for all drivers and driving conditions. Unnecessary Alerts FCA may provide unnecessary alerts for turning vehicles, vehicles in other lanes, objects that are not vehicles, or shadows. These alerts are normal operation and the vehicle does not need service. Cleaning the System If the FCA system does not seem to operate properly, cleaning the outside of the windshield in front of the camera sensor may correct the issue.

Lane Departure Warning (LDW) If equipped, LDW may help avoid crashes due to unintentional lane departures. It may provide a warning if the vehicle is crossing a

detected lane marking without using a turn signal in the lane departure direction. LDW uses a camera sensor to detect the lane markings. It only operates at speeds of 56 km/h (35 mph) or greater. When the vehicle crosses a detected lane marking, the LDW indicator will flash and either three beeps will be sounded from the left or right side, or three Safety Alert Seat pulses will occur on the left or right side of the seat, depending on the lane departure direction. LDW will not warn if the turn signal is on in the departure direction, or if a sharp maneuver is made. { Warning

The LDW system is an aid to help the vehicle stay in the driving lane. It does not steer the vehicle. The LDW system may not:

. Provide enough time to avoid

a crash.

(Continued)

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Warning (Continued)

. Detect lane markings under bad weather conditions or if the windshield is dirty.

. Detect lane markings and will

not detect road edges. . Warn that the vehicle is

crossing a lane marking if the system does not detect the lane marking.

If LDW only detects lane markings on one side of the road, it will only warn you when departing the lane on the side where it has detected a lane marker. Even with LDW, always keep your attention on the road and maintain proper vehicle position within the lane, or vehicle damage, injury, or death could occur. Always keep the windshield clean and do not use LDW in bad weather conditions.

How the System Works The LDW camera sensor is on the windshield ahead of the rearview mirror. To turn LDW on and off, press @ on the center stack. The control indicator will light when LDW is on.

When the vehicle is started, the LDW indicator on the instrument cluster will come on briefly. If LDW is on, the LDW indicator will appear green if the system detects a left or right lane marking while the vehicle is traveling at 56 km/h (35 mph) or greater. If the vehicle crosses a detected lane marking without using the turn signal in the lane departure direction, this indicator will change to amber and flash. In addition, three beeps will

Driving and Operating

9-67

be sounded from the left or right side, or the Safety Alert Seat will pulse three times on either the left or right side of the seat, depending on the lane departure direction. When the System Does Not Seem to Work Properly If the LDW symbol does not appear when the system is on and the vehicle is traveling at least 56 km/h (35 mph):

The lane markings on the road may not be seen. The camera sensor may be blocked by dirt, snow, or ice. The windshield may be damaged. The weather may be limiting visibility.

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Driving and Operating

Warning (Continued)

or windshield are not cleaned or in proper condition. Keep the windshield, headlamps, and camera sensors clean and in good repair.

LDW warnings may occur due to tar marks, shadows, cracks in the road, or other road imperfections. This is normal system operation; the vehicle does not need service.

Fuel For diesel engine vehicles, see “Fuel for Diesel Engines” in the Duramax diesel supplement. For gasoline engine vehicles, use of the recommended fuel is an important part of the proper maintenance of this vehicle. When driving in the U.S., to help keep the engine clean and maintain optimum vehicle performance, we recommend using TOP TIER Detergent Gasolines. See www.toptiergas.com for a list of TOP TIER Detergent Gasolines.

This is normal operation; the vehicle does not need service. Clean the windshield. Lane markings may not be detected on curves, highway exit ramps, or hills; or due to poor visibility. If the LDW camera system does not seem to operate properly, cleaning the outside of the windshield in front of the camera sensor may correct the issue.

{ Warning

LDW does not provide a warning to help avoid a crash, unless it detects the lane markings. LDW may not detect the lane markings if the camera sensor is blocked by dirt, snow, or ice, or if the windshield is damaged. It may also not detect a lane on winding or hilly roads, or in conditions that can limit visibility such as fog, rain, or snow, or if the headlamps (Continued)

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Driving and Operating

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If the vehicle has the 6.2L V8 engine (VIN Code J), use premium unleaded gasoline with a posted octane rating of 91 or higher. Regular unleaded gasoline rated at 87 octane or higher can be used, but acceleration could be reduced, and an audible knocking noise may be heard. If the octane is less than 87, a heavy knocking noise may be heard. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, the engine could be damaged. If heavy knocking is heard when using gasoline with a higher octane rating, the engine needs service.

Use of Seasonal Fuels Use summer and winter fuels in the appropriate season. Driving or starting could be affected if the incorrect fuel is used. Drive the vehicle with the engine running until the fuel is a half tank or less, then refuel with the current seasonal fuel.

Prohibited Fuels Gasolines containing oxygenates, such as ethers and ethanol, as well as reformulated gasolines are available in some cities. If these gasolines comply with the previousely described specification, then they are acceptable to use. However, E85 (85% ethanol) and other fuels containing more than 15% ethanol must be used only in flex fuel vehicles.

{ Caution

Do not use fuel containing methanol. It can corrode metal parts in the fuel system and also damage plastic and rubber parts. That damage would not be covered under the vehicle warranty.

If the vehicle has a yellow fuel cap, E85 or FlexFuel can be used in the vehicle. See E85 or FlexFuel on page 9-71. For all vehicles except those with the 6.2L V8 engine, use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise may be heard. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If heavy knocking is heard when using a higher octane rated gasoline, the engine needs service.

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Driving and Operating

Some gasolines that are not reformulated for low emissions can contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). Do not use gasolines with MMT as they can reduce spark plug life and affect emission control system performance. The malfunction indicator lamp may turn on. If this occurs, see your dealer for service.

Gasoline Specifications At a minimum, gasoline should meet ASTM specification D 4814. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). We recommend against the use of gasolines containing MMT. See “Prohibited Fuels" in Fuel on page 9-68.

California Fuel Requirements If the vehicle is certified to meet California Emissions Standards, it is designed to operate on fuels that meet California specifications. See the underhood emission control label. If this fuel is not available in states adopting California Emissions Standards, the vehicle will operate satisfactorily on fuels meeting federal specifications, but emission control system performance might be affected. The malfunction indicator lamp could turn on and the vehicle may not pass a smog-check test. See Malfunction Indicator Lamp on page 5-22. If this occurs, return to your authorized dealer for diagnosis. If it is determined that the condition is caused by the type of fuel used, repairs may not be covered by the vehicle warranty.

Fuels in Foreign Countries If planning to drive in countries outside the U.S. or Canada, the proper fuel might be hard to find. Check regional auto club or fuel retail brand websites for availability in the country where driving. Never use leaded gasoline, fuel containing methanol, or any other fuel not recommended. Costly repairs caused by use of improper fuel would not be covered by the vehicle warranty.

Fuel Additives To keep fuel systems clean, TOP TIER Detergent Gasoline is recommended. See Fuel on page 9-68. If TOP TIER Detergent Gasoline is not available, one bottle of Fuel System Treatment PLUS, part number 88861013, added to the fuel tank at every engine oil change, can help. Fuel System Treatment PLUS

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Driving and Operating

9-71

the fuel if the ethanol content is greater than 85%. Fuel mixtures that do not meet ASTM or CGSB specifications can affect driveability and could cause the malfunction indicator lamp to come on. After refueling, the vehicle calculates the composition of the fuel. It is not recommended to repeatedly switch between fuels. If fuels are switched frequently, add as much fuel as possible and do not add less than 11 L (3 gal) when refueling. Drive at least 11 km (7 mi) immediately after refueling to allow the vehicle to adapt to the change in ethanol concentration. Because E85 or FlexFuel has less energy per liter (gallon) than gasoline, the vehicle will need to be refilled more often. See Filling the Tank on page 9-72.

{ Caution Some additives are not compatible with E85 or FlexFuel and can harm the vehicle's fuel system. Do not add anything to E85 or FlexFuel. Damage caused by additives would not be covered by the vehicle warranty.

{ Caution

Do not use fuel containing methanol. It can corrode metal parts in the fuel system and also damage plastic and rubber parts. That damage would not be covered under the vehicle warranty.

is the only gasoline additive recommended by General Motors. It is available at your dealer. Do not use additives with E85 or FlexFuel.

E85 or FlexFuel Vehicles with a yellow fuel cap can use either unleaded gasoline or fuel containing up to 85% ethanol (E85). All other vehicles should use only the unleaded gasoline as described in Fuel on page 9-68. The use of E85 or FlexFuel is encouraged when the vehicle is designed to use it. E85 or FlexFuel is made from renewable sources. To help locate fuel stations that carry E85 or FlexFuel, the U.S. Department of Energy has an alternative fuels website. See www.afdc.energy.gov/afdc/locator/ stations. E85 or FlexFuel should meet ASTM Specification D 5798 or CAN/ CGSB–3.512 in Canada. Do not use

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Warning (Continued)

. Keep children away from the

fuel pump and never let children pump fuel.

. Fuel can spray out if the fuel

cap is opened too quickly. This spray can happen if the tank is nearly full, and is more likely in hot weather. Open the fuel cap slowly and wait for any hiss noise to stop then unscrew the cap all the way

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Driving and Operating

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

{ Warning

Fuel vapors and fuel fires burn violently and can cause injury or death.

. To help avoid injuries to you and others, read and follow all the instructions on the fuel pump island.

. Turn off the engine when

refueling.

. Keep sparks, flames, and

smoking materials away from fuel.

. Do not leave the fuel pump

unattended.

. Do not reenter the vehicle

while pumping fuel.

(Continued)

The fuel cap is behind a hinged fuel door on the driver side of the vehicle. Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). See E85
or FlexFuel on page 9-71. To remove the fuel cap, turn it slowly counterclockwise. If the vehicle is a dual fuel tank chassis cab model, and it runs out of fuel, refuel the front fuel tank first to ensure a quick restart.

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Be careful not to spill fuel. Do not top off or overfill the tank and wait a few seconds after you have finished pumping before removing the nozzle. Clean fuel from painted surfaces as soon as possible. See Exterior Care on page 10-96. When replacing the fuel cap, turn it clockwise until it clicks. It will require more effort to turn the fuel cap on the last turn as you tighten it. Make sure the cap is fully installed. The diagnostic system can determine if the fuel cap has been left off or improperly installed. This would allow fuel to evaporate into the atmosphere. See Malfunction Indicator Lamp on page 5-22. The TIGHTEN GAS CAP message displays on the Driver Information Center (DIC) if the fuel cap is not properly installed. See Fuel System Messages on page 5-38 for more information.

{ Warning

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

{ Caution

If a new fuel cap is needed, be sure to get the right type of cap from your dealer. The wrong type of fuel cap might not fit properly, might cause the malfunction indicator lamp to light, and could damage the fuel tank and emissions system. See Malfunction Indicator Lamp on page 5-22.

Driving and Operating

9-73

Filling a Portable Fuel Container

{ Warning

Filling a portable fuel container while it is in the vehicle can cause fuel vapors that can ignite either by static electricity or other means. You or others could be badly burned and the vehicle could be damaged. Always:

. Use approved fuel

containers.

. Remove the container from the vehicle, trunk, or pickup bed before filling.

. Place the container on the

ground.

. Place the nozzle inside the fill

opening of the container before dispensing fuel, and

(Continued)

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Driving and Operating

Warning (Continued)

keep it in contact with the fill opening until filling is complete.

. Fill the container no more than 95% full to allow for expansion.

. Do not smoke, light matches,

or use lighters while pumping fuel.

. Avoid using cell phones or

other electronic devices.

Trailer Towing

General Towing Information Only use towing equipment that has been designed for the vehicle. Contact your dealer or trailering dealer for assistance with preparing the vehicle for towing a trailer. Read the entire section before towing a trailer. For towing a disabled vehicle, see Towing the Vehicle on page 10-94. For towing the vehicle behind another vehicle such as a motor home, see Recreational Vehicle Towing on page 10-94.

Driving Characteristics and Towing Tips

Driving with a Trailer When towing a trailer: . Become familiar with the state

and local laws that apply to trailer towing.

. Do not tow a trailer during the first 800 km (500 mi) to prevent damage to the engine, axle, or other parts. Then during the first 800 km (500 mi) of trailer towing, do not drive over 80 km/h (50 mph) and do not make starts at full throttle.

. Vehicles can tow in D (Drive).

Shift the transmission to a lower gear if the transmission shifts too often under heavy loads and/ or hilly conditions. Turn off Park Assist when towing.

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{ Warning

When towing a trailer, exhaust gases may collect at the rear of the vehicle and enter if the liftgate, trunk/hatch, or rear-most window is open. When towing a trailer:

. Do not drive with the liftgate,

trunk/hatch, or rear-most window open.

. Fully open the air outlets on

or under the instrument panel.

. Also adjust the climate

control system to a setting that brings in only outside air. See “Climate Control Systems” in the Index. For more information about Carbon Monoxide, see Engine Exhaust on page 9-33.

Towing a trailer requires a certain amount of experience. The combination you are driving is longer and not as responsive as the vehicle itself. Get acquainted with the handling and braking of the rig before setting out for the open road. Before starting, check all trailer hitch parts and attachments, safety chains, electrical connectors, lamps, tires, and mirrors. If the trailer has electric brakes, start the combination moving and then apply the trailer brake controller by hand to be sure the brakes work. During the trip, check occasionally to be sure that the load is secure and the lamps and any trailer brakes still work. Following Distance Stay at least twice as far behind the vehicle ahead as you would when driving the vehicle without a trailer. This can help to avoid heavy braking and sudden turns.

Passing More passing distance is needed when towing a trailer. The combination will not accelerate as quickly and is longer so it is necessary to go much farther beyond the passed vehicle before returning to the lane. Backing Up Hold the bottom of the steering wheel with one hand. To move the trailer to the left, move that hand to the left. To move the trailer to the right, move your hand to the right. Always back up slowly and, if possible, have someone guide you.

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Driving and Operating

Making Turns

{ Caution

Making very sharp turns while trailering could cause the trailer to come in contact with the vehicle. The vehicle could be damaged. Avoid making very sharp turns while trailering.

When turning with a trailer, make wider turns than normal. Do this so the trailer will not strike soft shoulders, curbs, road signs, trees, or other objects. Avoid jerky or sudden maneuvers. Signal well in advance. If the trailer turn signal bulbs burn out, the arrows on the instrument cluster will still flash for turns. It is important to check occasionally to be sure the trailer bulbs are still working.

Driving on Grades Reduce speed and shift to a lower gear before starting down a long or steep downgrade. If the transmission is not shifted down, the brakes might get hot and no longer work well. Vehicles can tow in D (Drive). Shift the transmission to a lower gear if the transmission shifts too often under heavy loads and/or hilly conditions. The Tow/Haul Mode may be used if the transmission shifts too often. See Tow/Haul Mode on page 9-38. When towing at high altitude on steep uphill grades, consider the following: Engine coolant will boil at a lower temperature than at normal altitudes. If the engine is turned off immediately after towing at high altitude on steep uphill grades, the vehicle may show signs similar to engine overheating. To avoid this, let the engine run while parked, preferably on level ground, with the transmission in P (Park) for a few

minutes before turning the engine off. If the overheat warning comes on, see Engine Overheating on page 10-23. Parking on Hills

{ Warning

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

If parking the rig on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the wheels into the curb if facing downhill or into traffic if facing uphill.

2. Have someone place chocks

under the trailer wheels.

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especially important in trailer operation are automatic transmission fluid, engine oil, axle lubricant, belts, cooling system, and brake system. It is a good idea to inspect these before and during the trip. Check periodically to see that all hitch nuts and bolts are tight.

Trailer Towing If the vehicle has a diesel engine, see the Duramax diesel supplement. If the vehicle is bi-fuel, see the bi-fuel supplement. Do not tow a trailer during break-in. See New Vehicle Break-In on page 9-24.

{ Warning

The driver can lose control when pulling a trailer if the correct equipment is not used or the vehicle is not driven properly. For example, if the trailer is too heavy, the brakes may not work well or even at all. The driver and passengers could be seriously injured. The vehicle may also be damaged; the resulting repairs would not be covered by the vehicle warranty. Pull a trailer only if all the steps in this section have been followed. Ask your dealer for advice and information about towing a trailer with the vehicle.

3. When the wheel chocks are in

place, release the regular brakes until the chocks absorb the load.

4. Reapply the brake pedal. Then

apply the parking brake and shift into P (Park).

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

clear of the chocks.

7. Stop and have someone pick up

and store the chocks.

Maintenance when Trailer Towing The vehicle needs service more often when pulling a trailer. See Maintenance Schedule on page 11-3. Things that are

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For kingpin weight and trailer tongue weight information, see “Weight of the Trailer Tongue” later in this section. Use the following chart to determine how much the vehicle can weigh, based upon the vehicle model and options. Weights listed apply for conventional trailers and fifth-wheel trailers unless otherwise noted.

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Driving and Operating

{ Caution

Pulling a trailer improperly can damage the vehicle and result in costly repairs not covered by the vehicle warranty. To pull a trailer correctly, follow the advice in this section and see your dealer for important information about towing a trailer with the vehicle.

To identify the trailering capacity of the vehicle, read the information in “Weight of the Trailer” later in this section. Trailering is different than just driving the vehicle by itself. Trailering means changes in handling, acceleration, braking, durability, and fuel economy. Successful, safe trailering takes correct equipment, and it has to be used properly. The following information has many time-tested, important trailering tips and safety rules. Many of these are

important for your safety and that of your passengers. Read this section carefully before pulling a trailer. Weight of the Trailer How heavy can a trailer safely be? It depends on how the rig is used. Speed, altitude, road grades, outside temperature, and how much the vehicle is used to pull a trailer are all important. It can depend on any special equipment on the vehicle, and the amount of tongue weight the vehicle can carry. See “Weight of the Trailer Tongue” later in this section for more information. Trailer weight rating (TWR) is calculated assuming the tow vehicle has only the driver but all required trailering equipment. Weight of additional optional equipment, passengers, and cargo in the tow vehicle must be subtracted from the trailer weight rating.

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Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

1500 Series 2WD Regular Cab Standard Box

4.3L V6 (b) 4.3L V6 (b) 5.3L V8
5.3L V8

1500 Series 2WD Double Cab Standard Box

4.3L V6 (b) 5.3L V8
5.3L V8
5.3L V8
6.2L V8
6.2L V8

1500 Series 2WD Crew Cab Standard Box

4.3L V6 (b) 5.3L V8
5.3L V8
5.3L V8

3.23
4.10
3.08
3.42

3.23
3.08
3.42
3.73
3.42
3.73

3.23
3.08
3.42
3.73

2 903 kg (6,400 lb) 2 223 kg (4,900 lb) 3 311 kg (7,300 lb) 4 218 kg (9,300 lb)

2 722 kg (6,000 lb) 3 130 kg (6,900 lb) 4 491 kg (9,900 lb) 5 216 kg (11,500 lb) 4 445 kg (9,800 lb) 5 443 kg (12,000 lb)

2 631 kg (5,800 lb) 3 039 kg (6,700 lb) 4 400 kg (9,700 lb) 5 126 kg (11,300 lb)

4 990 kg (11,000 lb) 4 309 kg (9,500 lb) 5 443 kg (12,000 lb) 6 350 kg (14,000 lb)

4 990 kg (11,000 lb) 5 443 kg (12,000 lb) 6 804 kg (15,000 lb) 7 575 kg (16,700 lb) 6 804 kg (15,000 lb) 7 938 kg (17,500 lb)

4 990 kg (11,000 lb) 5 443 kg (12,000 lb) 6 804 kg (15,000 lb) 7 575 kg (16,700 lb)

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Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

6.2L V8
6.2L V8

1500 Series 2WD Crew Cab Short Box (b)

4.3L V6
5.3L V8
5.3L V8
5.3L V8
6.2L V8
6.2L V8

1500 Series 2WD Regular Cab Long Box

4.3L V6 (b) 5.3L V8
5.3L V8

1500 Series 4WD Regular Cab Standard Box

4.3L V6 (b) 5.3L V8
5.3L V8

3.42
3.73

3.23
3.08
3.42
3.73
3.42
3.73

3.23
3.08
3.42

3.42
3.08
3.42

4 355 kg (9,600 lb) 5 443 kg (12,000 lb)

6 804 kg (15,000 lb) 7 938 kg (17,500 lb)

2 676 kg (5,900 lb) 3 084 kg (6,800 lb) 4 445 kg (9,800 lb) 5 171 kg (11,400 lb) 4 400 kg (9,700 lb) 5 443 kg (12,000 lb)

4 990 kg (11,000 lb) 5 443 kg (12,000 lb) 6 804 kg (15,000 lb) 7 575 kg (16,700 lb) 6 804 kg (15,000 lb) 7 938 kg (17,500 lb)

2 858 kg (6,300 lb) 3 266 kg (7,200 lb) 4 627 kg (10,200 lb)

4 990 kg (11,000 lb) 5 443 kg (12,000 lb) 6 804 kg (15,000 lb)

3 266 kg (7,200 lb) 3 221 kg (7,100 lb) 4 128 kg (9,100 lb)

5 443 kg (12,000 lb) 5 443 kg (12,000 lb) 6 350 kg (14,000 lb)

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Driving and Operating

9-81

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

1500 Series 4WD Double Cab Standard Box

4.3L V6 (b) 5.3L V8
5.3L V8
5.3L V8
6.2L V8
6.2L V8

1500 Series 4WD Crew Cab Standard Box

4.3L V6 (b) 5.3L V8
5.3L V8
5.3L V8
6.2L V8
6.2L V8

1500 Series 4WD Crew Cab Short Box (b)

4.3L V6
5.3L V8

3.42
3.08
3.42
3.73
3.42
3.73

3.42
3.08
3.42
3.73
3.42
3.73

3.42
3.08

3 039 kg (6,700 lb) 2 994 kg (6,600 lb) 4 354 kg (9,600 lb) 5 080 kg (11,200 lb) 4 309 kg (9,500 lb) 5 352 kg (11,800 lb)

2 994 kg (6,600 lb) 2 948 kg (6,500 lb) 4 309 kg (9,500 lb) 5 035 kg (11,100 lb) 4 264 kg (9,400 lb) 5 307 kg (11,700 lb)

5 443 kg (12,000 lb) 5 443 kg (12,000 lb) 6 804 kg (15,000 lb) 7 575 kg (16,700 lb) 6 804 kg (15,000 lb) 7 938 kg (17,500 lb)

5 443 kg (12,000 lb) 5 443 kg (12,000 lb) 6 804 kg (15,000 lb) 7 575 kg (16,700 lb) 6 804 kg (15,000 lb) 7 938 kg (17,500 lb)

3 039 kg (6,700 lb) 2 994 kg (6,600 lb)

5 443 kg (12,000 lb) 5 443 kg (12,000 lb)

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Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

5.3L V8
5.3L V8
6.2L V8
6.2L V8

1500 Series 4WD Regular Cab Long Box

4.3L V6 (b) 5.3L V8
5.3L V8

2500 Series 2WD Crew Cab Standard Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 – Fifth-Wheel Trailer

2500 Series 2WD Regular Cab Long Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 – Fifth-Wheel Trailer

3.42
3.73
3.42
3.73

3.42
3.08
3.42

3.73
4.10
4.10

3.73
4.10
4.10

4 354 kg (9,600 lb) 5 352 kg (11,800 lb) 4 309 kg (9,500 lb) 5 352 kg (11,800 lb)

6 804 kg (15,000 lb) 7 938 kg (17,500 lb) 6 804 kg (15,000 lb) 7 938 kg (17,500 lb)

3 175 kg (7,000 lb) 3 130 kg (6,900 lb) 4 491 kg (9,900 lb)

5 443 kg (12,000 lb) 5 443 kg (12,000 lb) 6 804 kg (15,000 lb)

4 400 kg (9,700 lb) 5 897 kg (13,000 lb) 6 441 kg (14,200 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

4 627 kg (10,200 lb) 5 897 kg (13,000 lb) 6 668 kg (14,700 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

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Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

Driving and Operating

9-83

2500 Series 2WD Crew Cab Long Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 – Fifth-Wheel Trailer

2500 Series 4WD Crew Cab Standard Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 – Fifth-Wheel Trailer

2500 Series 4WD Regular Cab Long Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 – Fifth-Wheel Trailer

2500 Series 4WD Crew Cab Long Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 – Fifth-Wheel Trailer

3.73
4.10
4.10

3.73
4.10
4.10

3.73
4.10
4.10

3.73
4.10
4.10

4 354 kg (9,600 lb) 5 897 kg (13,000 lb) 6 396 kg (14,100 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

4 264 kg (9,400 lb) 5 897 kg (13,000 lb) 6 305 kg (13,900 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

4 491 kg (9,900 lb) 5 897 kg (13,000 lb) 6 532 kg (14,400 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

4 218 kg (9,300 lb) 5 897 kg (13,000 lb) 6 260 kg (13,800 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

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9-84

Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

3500 Series 2WD Regular Cab Long Box

6.0L V8 (Single Rear Wheels) Conventional Trailer 6.0L V8 (Single Rear Wheels) Fifth-Wheel Trailer 6.0L V8 (Dual Rear Wheels) 6.0L V8 (Dual Rear Wheels) Conventional Trailer 6.0L V8 (Dual Rear Wheels) Fifth-Wheel Trailer

3500 Series 2WD Crew Cab Standard Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 Fifth-Wheel Trailer

3500 Series 2WD Crew Cab Long Box

6.0L V8 (Single Rear Wheels) 6.0L V8 (Single Rear Wheels) Conventional Trailer

4.10

4.10

3.73
4.10

4.10

3.73
4.10
4.10

3.73
4.10

5 897 kg (13,000 lb)

9 299 kg (20,500 lb)

6 577 kg (14,500 lb)

9 299 kg (20,500 lb)

4 354 kg (9,600 lb) 6 396 kg (14,100 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb)

6 441 kg (14,200 lb)

9 299 kg (20,500 lb)

4 309 kg (9,500 lb) 5 897 kg (13,000 lb) 6 350 kg (14,000 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

4 264 kg (9,400 lb) 5 897 kg (13,000 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb)

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Driving and Operating

9-85

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

6.0L V8 (Single Rear Wheels) Fifth-Wheel Trailer 6.0L V8 (Dual Rear Wheels) 6.0L V8 (Dual Rear Wheels)

3500 Series 4WD Regular Cab Long Box

6.0L V8 (Single Rear Wheels) 6.0L V8 (Single Rear Wheels) Conventional Trailer 6.0L V8 (Single Rear Wheels) Fifth-Wheel Trailer 6.0L V8 (Dual Rear Wheels) 6.0L V8 (Dual Rear Wheels)

3500 Series 4WD Crew Cab Standard Box

6.0L V8
6.0L V8 – Conventional Trailer 6.0L V8 – Fifth-Wheel Trailer

3500 Series 4WD Crew Cab Long Box

6.0L V8 (Single Rear Wheels)

4.10

3.73
4.10

3.73
4.10

4.10

3.73
4.10

3.73
4.10
4.10

3.73

6 305 kg (13,900 lb)

9 299 kg (20,500 lb)

4 082 kg (9,000 lb) 6 123 kg (13,500 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb)

4 400 kg (9,700 lb) 5 897 kg (13,000 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb)

6 441 kg (14,200 lb)

9 299 kg (20,500 lb)

4 218 kg (9,300 lb) 6 260 kg (13,800 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb)

4 173 kg (9,200 lb) 5 897 kg (13,000 lb) 6 214 kg (13,700 lb)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) 9 299 kg (20,500 lb)

4 128 kg (9,100 lb)

7 257 kg (16,000 lb)

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9-86

Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

4.10

4.10

5 897 kg (13,000 lb)

9 299 kg (20,500 lb)

6 169 kg (13,600 lb)

9 299 kg (20,500 lb)

6.0L V8 (Single Rear Wheels) Conventional Trailer 6.0L V8 (Single Rear Wheels) Fifth-Wheel Trailer 6.0L V8 (Dual Rear Wheels) 6.0L V8 (Dual Rear Wheels)

7 257 kg (16,000 lb) 9 299 kg (20,500 lb) (a) The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and trailer including any passengers, cargo, equipment, and conversions. The GCWR for the vehicle should not be exceeded. (b) This model is neither designed nor intended to tow fifth-wheel or gooseneck trailers.

3 946 kg (8,700 lb) 5 987 kg (13,200 lb)

3.73
4.10

Ask your dealer for trailering information or advice. Weight of the Trailer Tongue The tongue load (1) of any trailer is very important because it is also part of the vehicle weight. The Gross Vehicle Weight (GVW) includes the curb weight of the

vehicle, any cargo carried in it, and the people who will be riding in the vehicle as well as trailer tongue weight. Vehicle options, equipment, passengers and cargo in the vehicle reduce the amount of tongue weight

the vehicle can carry, which will also reduce the trailer weight the vehicle can tow. See Vehicle Load Limits on page 9-16 for more information about the vehicle's maximum load capacity.

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Driving and Operating

9-87

Vehicle Series

1500
1500
2500/3500
Standard Box 2500/ 3500 Long Box 2500
3500 Single Rear Wheels 3500 Dual Rear Wheels

Hitch Type

Weight-Carrying

Weight-Distributing Weight-Carrying or Weight-Distributing Weight-Carrying or Weight-Distributing

Maximum Tongue

Weight

363 kg (800 lb) 544 kg (1,200 lb) 680 kg (1,500 lb)

907 kg (2,000 lb)

Fifth-Wheel Gooseneck Fifth-Wheel Gooseneck

1 361 kg (3,000 lb) 1 814 kg (4,000 lb)

Fifth-Wheel Gooseneck

2 495 kg (5,500 lb)

Do not exceed the maximum allowable tongue weight for the vehicle. Choose the shortest hitch extension that will position the hitch ball closest to the vehicle. This will help reduce the effect of trailer tongue weight on the rear axle.

Trailer rating may be limited by the vehicle's ability to carry tongue weight. Tongue or kingpin weight cannot cause the vehicle to exceed the GVWR (Gross Vehicle Weight Rating) or the RGAWR (Rear Gross Axle Weight Rating). See “Total Weight on the Vehicle's Tires” later in this section.

Trailer tongue weight (1) should be 10–15 percent and fifth-wheel or gooseneck kingpin weight should be 15–25 percent of the loaded trailer weight up to the maximums for vehicle series and hitch type.

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9-88

Driving and Operating

After loading the trailer, weigh the trailer and then the tongue, separately, to see if the weights are proper. If they are not, adjustments might be made by moving some items around in the trailer. If a cargo carrier is used in the trailer hitch receiver, choose a carrier that positions the load as close to the vehicle as possible. Make sure the total weight, including the carrier, is no more than half of the maximum allowable tongue weight for the vehicle or 227 kg (500 lb), whichever is less.

Total Weight on the Vehicle's Tires Be sure the vehicle's tires are inflated to the inflation pressures found on the Certification/Tire label on the center pillar or see Vehicle Load Limits on page 9-16. Make sure not to exceed the GVWR limit for the vehicle, or the RGAWR, with the tow vehicle and trailer fully loaded for the trip including the weight of the trailer tongue. If using a weight-distributing hitch, make sure not to exceed the RGAWR before applying the weight distribution spring bars.

Weight of the Trailering Combination It is important that the combination of the tow vehicle and trailer does not exceed any of its weight ratings — GCWR, GVWR, RGAWR, Trailer Weight Rating, or Tongue Weight. The only way to be sure it is not exceeding any of these ratings is to weigh the tow vehicle and trailer combination, fully loaded for the trip, getting individual weights for each of these items.

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Driving and Operating

9-89

Towing Equipment

Hitches The correct hitch equipment helps maintain combination control. Many trailers can be towed with a weight-carrying hitch which simply features a coupler latched to the hitch ball, or a tow eye latched to a pintle hook. Other trailers may require a weight-distributing hitch that uses spring bars to distribute the trailer tongue weight among the two vehicle and trailer axles. Fifth-wheel and gooseneck hitches may also be used. See “Weight of the Trailer Tongue” under Trailer Towing on page 9-77 for rating limits with various hitch types.

If a step-bumper hitch will be used, the bumper could be damaged in sharp turns. Make sure there is ample room when turning to avoid contact between the trailer and the bumper. Consider using sway controls with any trailer. Ask a trailering professional about sway controls or refer to the trailer manufacturer's recommendations and instructions. Weight-Distributing Hitch and Adjustment A weight distributing hitch may be useful with some trailers. Use the following guidelines to determine if a weight distributing hitch should be used.

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Driving and Operating

Weight Distributing Hitch

Vehicle Series

1500

1500
2500/3500

Trailer Weight Up to 7,000 lb

Over 7,000 lb Up to 18,000 lb

Usage Optional

Required Optional

Hitch Distribution

Refer to trailer manufacturer’s recommendation

50%

Refer to trailer manufacturer’s recommendation

When using a weight-distributing hitch, measure distance (1) before coupling the trailer to the hitch ball. Measure the height again after the trailer is coupled and adjust the spring bars so the distance (1) is as close as possible to halfway between the two measurements. Fifth-Wheel and Gooseneck Trailering Fifth-wheel and gooseneck trailers can be used with many pickup models. These trailers place a larger percentage of the weight

(kingpin weight) on the tow vehicle than conventional trailers. Make sure this weight does not cause the vehicle to exceed GAWR or GVWR. Fifth-wheel or gooseneck kingpin weight should be 15 to 25 percent of the trailer weight up to the maximum amount specified in the trailering chart for the vehicle. See “Weight of the Trailer” under Trailer Towing on page 9-77. The hitch should be located in the pickup bed so that its centerline is over or slightly in front of the rear axle. Take care that it is not so far

1. Body to Ground Distance 2. Front of Vehicle

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forward that it will contact the back of the cab in sharp turns. This is especially important for short box pickups. Trailer pin box extensions and sliding fifth-wheel hitch assemblies can help this condition. There should be at least 15 cm (6 in) of clearance between the top of the pickup box and the bottom of the trailer shelf that extends over the box. Make sure the hitch is attached to the tow vehicle frame rails. Do not use the pickup box for support. Safety Chains Always attach chains between the vehicle and the trailer. Cross the safety chains under the tongue of the trailer to help prevent the tongue from contacting the road if it becomes separated from the hitch. Instructions about safety chains may be provided by the hitch manufacturer or by the trailer manufacturer. If the trailer being towed weighs up to 2 271 kg (5,000 lb) with a factory-installed

Driving and Operating

9-91

step bumper, safety chains may be attached to the attaching points on the bumper; otherwise, safety chains should be attached to holes on the trailer hitch platform. Always leave just enough slack so the combination can turn. Never allow safety chains to drag on the ground. Trailer Brakes A loaded trailer that weighs more than 900 kg (2,000 lb) needs to have its own brake system that is adequate for the weight of the trailer. Be sure to read and follow the instructions for the trailer brakes so they are installed, adjusted, and maintained properly. Do not tap into the vehicle's hydraulic brake system. Auxiliary Battery The auxiliary battery provision can be used to supply electrical power to additional equipment that may be added, such as a slide-in camper.

If equipped, this relay will be on the driver side of the vehicle, next to the underhood electrical center. Be sure to follow the proper installation instructions included with any electrical equipment that is installed.

{ Caution

Leaving electrical equipment on for extended periods will drain the battery. Always turn off electrical equipment when not in use and do not use equipment that exceeds the maximum amperage rating of 30 amps for the auxiliary battery provision.

Trailer Wiring Harness The vehicle is equipped with one of the following wiring harnesses for towing a trailer or hauling a slide-in camper.

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9-92

Driving and Operating

Basic Trailer Wiring All regular, double cab, and crew cab pickups have a seven-wire trailer towing harness. For vehicles not equipped with heavy duty trailering, the harness is secured to the vehicle's frame behind the spare tire mount. The harness requires the installation of a trailer connector, which is available through your dealer.

Heavy-Duty Trailer Wiring Harness Package

For vehicles equipped with heavy-duty trailering, the harness connector is mounted in the bumper. The seven-wire harness contains the following trailer circuits: . Green/Violet: Left Stop/Turn

Signal

. Yellow/Gray: Right Stop/Turn

Signal

. Gray/Brown: Taillamps/

Parklamps

. White: Ground . White/Green: Back-up Lamps . Red/Green: Battery Feed . Dark Blue: Trailer Brake If charging a remote (non-vehicle) battery, press the Tow/Haul Mode button, if equipped, located at the end of the shift lever. This will boost the vehicle system voltage and properly charge the battery. If the trailer is too light for Tow/Haul Mode, or the vehicle is not equipped with Tow/Haul, turn on the

headlamps as a second way to boost the vehicle system and charge the battery.

Camper/Fifth-Wheel Trailer Wiring Package The seven-wire camper harness is under the rear bumper, attached to the frame near the rear crossmember. A connector must be added to the wiring harness that connects to the camper. The harness contains the following camper/trailer circuits: . Green/Violet: Left Stop/Turn

Signal

. Yellow/Gray: Right Stop/Turn

Signal

. Gray/Brown: Taillamps/

Parklamps

. White: Ground . White/Green: Back-up Lamps . Red/Green: Battery Feed . Dark Blue: Trailer Brake

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Driving and Operating

9-93

If the vehicle is equipped with the heavy-duty trailering option, see “Heavy-Duty Trailer Wiring Harness Package” earlier in this section. When the camper-wiring harness is ordered without the heavy-duty trailering package, a seven-wire harness with a seven-pin connector is at the rear of the vehicle and is tied to the vehicle's frame. Electric Brake Control Wiring Provisions These wiring provisions are included with the vehicle as part of the trailer wiring package. These provisions are for an electric brake controller. The harness should be installed by your dealer or a qualified service center.

Tow/Haul Mode

Pressing this button at the end of the shift lever turns on and off the Tow/Haul Mode.

This indicator light on the instrument cluster comes on when the Tow/ Haul Mode is on.

Tow/Haul is a feature that assists when pulling a heavy trailer or a large or heavy load. See Tow/Haul Mode on page 9-38. Tow/Haul is designed to be most effective when the vehicle and trailer combined weight is at least 75 percent of the vehicle's Gross Combined Weight Rating (GCWR). See “Weight of the Trailer” under Trailer Towing on page 9-77. Tow/ Haul is most useful under the following driving conditions: . When pulling a heavy trailer or a

large or heavy load through rolling terrain.

. When pulling a heavy trailer or a

large or heavy load in stop-and-go traffic.

. When pulling a heavy trailer or a

large or heavy load in busy parking lots where improved low speed control of the vehicle is desired.

GMC Sierra Owner Manual