2013 GMC Sierra Owners Manual

the underhood emission control

label. If this fuel is not available in states adopting California Emissions Standards, the vehicle will operate satisfactorily on fuels meeting federal specifications, but emission control system performance might be affected. The malfunction indicator lamp could turn on and the vehicle might fail a smog‐check test. See Malfunction Indicator Lamp on page 5‑21. If this occurs, return to your authorized dealer for diagnosis. If it is determined that the condition is caused by the type of fuel used, repairs might not be covered by the vehicle warranty.

Fuels in Foreign Countries Never use leaded gasoline or any other fuel not recommended in the previous text on fuel. Costly repairs caused by use of improper fuel would not be covered by the vehicle warranty.

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Driving and Operating

9-67

To check the fuel availability, ask an auto club, or contact a major oil company that does business in the country where you will be driving.

Fuel Additives To provide cleaner air, all gasolines in the United States are now required to contain additives that help prevent engine and fuel system deposits from forming, allowing the emission control system to work properly. In most cases, nothing should have to be added to the fuel. However, some gasolines contain only the minimum amount of additive required to meet U.S. Environmental Protection Agency regulations. To help keep fuel injectors and intake valves clean and avoid problems due to dirty injectors or valves, look for gasoline that is advertised as TOP TIER Detergent Gasoline. Look for the TOP TIER label on the fuel pump to ensure gasoline meets enhanced detergency standards developed by the auto companies. A list of

marketers providing TOP TIER Detergent Gasoline can be found at www.toptiergas.com. For customers who do not use TOP TIER Detergent Gasoline regularly, one bottle of GM Fuel System Treatment PLUS, added to the fuel tank at every engine oil change, can help clean deposits from fuel injectors and intake valves. GM Fuel System Treatment PLUS is the only gasoline additive recommended by General Motors. It is available at your dealer. Gasolines containing oxygenates, such as ethers and ethanol, and reformulated gasolines might be available in your area. We recommend that you use these gasolines, if they comply with the specifications described earlier. However, E85 (85% ethanol) and other fuels containing more than 15% ethanol must not be used in vehicles that were not designed for those fuels.

Notice: This vehicle was not designed for fuel that contains methanol. Do not use fuel containing methanol. It can corrode metal parts in the fuel system and also damage plastic and rubber parts. That damage would not be covered under the vehicle warranty. Some gasolines that are not reformulated for low emissions can contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT); ask the attendant where you buy gasoline whether the fuel contains MMT. We recommend against the use of such gasolines. Fuels containing MMT can reduce spark plug life and affect emission control system performance. The malfunction indicator lamp might turn on. If this occurs, return to your dealer for service.

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Driving and Operating

Fuel E85 (85% Ethanol) Vehicles that have a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). For all other vehicles, use only the unleaded gasoline described under Recommended Fuel on page 9‑66. We encourage the use of E85 in vehicles that are designed to use it. The ethanol in E85 is a “renewable” fuel, meaning it is made from renewable sources such as corn and other crops. Many service stations will not have an 85% ethanol fuel (E85) pump available. The U.S. Department of Energy has an alternative fuels website (www.afdc.energy.gov/afdc/ locator/stations/) that can help you find E85 fuel. Those stations that do have E85 should have a label indicating ethanol content. Do not use the fuel if the ethanol content is greater than 85%.

At a minimum, E85 should meet ASTM Specification D 5798 or CGSB Specification 3.512. Filling the tank with fuel mixtures that do not meet ASTM or CGSB specifications can affect driveability and could cause the malfunction indicator lamp to come on. As the outside temperature approaches freezing, ethanol fuel distributors should supply winter grade ethanol, the same as with unleaded gasoline. It is best not to alternate repeatedly between gasoline and E85. If you do switch fuels, it is recommended that you add as much fuel as possible — do not add less than 11 L (3 gal) when refueling. You should drive the vehicle immediately after refueling for at least 11 km (7 mi) to allow the vehicle to adapt to the change in ethanol concentration. E85 has less energy per liter (gallon) than gasoline, so you will need to refill the fuel tank more

often when using E85 than when you are using gasoline. See Filling the Tank on page 9‑68. Notice: Some additives are not compatible with E85 fuel and can harm the vehicle's fuel system. Do not add anything to E85. Damage caused by additives would not be covered by the vehicle warranty. Notice: This vehicle was not designed for fuel that contains methanol. Do not use fuel containing methanol. It can corrode metal parts in the fuel system and also damage plastic and rubber parts. That damage would not be covered under the vehicle warranty.

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

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{ 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.

. Keep children away from the

fuel pump and never let children pump fuel.

(Continued)

WARNING (Continued)

. 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

The tethered fuel cap is located behind a hinged fuel door on the driver side of the vehicle. Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). See Fuel E85 (85% Ethanol) on page 9‑68. 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.

Driving and Operating

9-69

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 10‑91. 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 5‑21. 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 5‑41 for more information.

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Driving and Operating

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

Notice: If a new fuel cap is needed, be sure to get the right type of cap from your dealer. The wrong type of fuel cap might not fit properly, might cause the malfunction indicator lamp to light, and could damage the fuel tank and emissions system. See Malfunction Indicator Lamp on page 5‑21.

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 container from

vehicle, trunk, or pickup bed before filling.

(Continued)

WARNING (Continued)

. Place container on the

ground.

. Place the nozzle inside the fill

opening of the container before dispensing fuel, and keep it in contact with the fill opening until filling is complete.

. Do not smoke while

pumping fuel.

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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 10‑87. For towing the vehicle behind another vehicle such as a motor home, see Recreational Vehicle Towing on page 10‑87.

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.

{ 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.

(Continued)

WARNING (Continued)

. 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 System” in the Index.

For more information about Carbon Monoxide, see Engine Exhaust on page 9‑31.

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

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Driving and Operating

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. Making Turns Notice: Making very sharp turns while trailering could cause the trailer to come in contact with the vehicle. The vehicle could be damaged. Avoid making very sharp turns while trailering. When turning with a trailer, make wider turns than normal. Do this so the trailer will not strike soft shoulders, curbs, road signs, trees, or other objects. Avoid jerky or sudden maneuvers. Signal well in advance. If the trailer turn signal bulbs burn out, the arrows on the instrument 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 9‑37. 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 automatic transmission in P (Park)

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Driving and Operating

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for a few minutes before turning the engine off. If the overheat warning comes on, see Engine Overheating on page 10‑20. Parking on Hills

{ WARNING

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

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

2. Have someone place chocks

under the trailer wheels.

3. When the wheel chocks are in

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

4. Reapply the brake pedal. Then

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

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

Trailer Towing If the vehicle has a diesel engine, see the Duramax diesel supplement for more information. If the vehicle is a hybrid, see the hybrid supplement for more information. If the vehicle is bi-fuel, see the bi-fuel supplement for more information. Do not tow a trailer during break-in. See New Vehicle Break-In on page 9‑23 for more information.

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Driving and Operating

{ 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.

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

section and see your dealer 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. So please 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. 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.

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Driving and Operating

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Weights listed apply for conventional trailers and fifth-wheel trailers unless otherwise noted.

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

1500 Series 2WD Regular Cab Standard Box

4.3L V6 (b) 4.3L V6 — With Automatic Transmission (b) 4.3L V6 — With Manual Transmission (b) 4.8L V8 (b) 4.8L V8 (b) 5.3L LMG V8 (b) 5.3L LMG V8, K5L HD Cooling Pkg 5.3L LMG V8 K5L HD Cooling Pkg

3.23
3.73

3.73

3.23
3.73
3.08
3.08

3.42

1500 Series 2WD Extended Cab Standard Box

2 177 kg (4,800 lbs) 2 449 kg (5,400 lbs)

4 309 kg (9,500 lbs) 4 536 kg (10,000 lbs)

1 860 kg (4,100 lbs)

3 938 kg (8,683 lbs)

2 132 kg (4,700 lbs) 3 266 kg (7,200 lbs) 2 994 kg (6,600 lbs) 3 357 kg (7,400 lbs)

4 309 kg (9,500 lbs) 5 443 kg (12,000 lbs) 5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs)

4 128 kg (9,100 lbs)

6 350 kg (14,000 lbs)

4.3L V6 (b) 4.8L V8 (b) 4.8L V8 (b) 5.3L V8 (b)

3.23
3.23
3.73
3.08

1 996 kg (4,400 lbs) 2 132 kg (4,700 lbs) 3 039 kg (6,700 lbs) 2 812 kg (6,200 lbs)

4 309 kg (9,500 lbs) 4 536 kg (10,000 lbs) 5 443 kg (12,000 lbs) 5 216 kg (11,500 lbs)

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Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

5.3L V8 K5L HD Cooling Pkg (b) 5.3L V8 K5L HD Cooling Pkg — Conventional Trailer 5.3L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer 6.2L V8 K5L HD Cooling Pkg — Conventional Trailer 6.2L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer 6.2L V8 NHT Max Trailering Pkg — Conventional Trailer 6.2L V8 NHT Max Trailering Pkg — Fifth-Wheel Trailer

1500 Series 2WD Crew Cab Short Box (b)

4.8L V8
4.8L V8
5.3L V8 (LMG) 5.3L V8 (LMG) K5L HD Cooling Pkg

3.08
3.42

3.42

3.42

3.42

3.73

3.73

3.23
3.73
3.08
3.08

3 130 kg (6,900 lbs) 4 400 kg (9,700 lbs)

5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs)

4 264 kg (9,400 lbs)

6 804 kg (15,000 lbs)

4 400 kg (9,700 lbs)

6 804 kg (15,000 lbs)

4 264 kg (9,400 lbs)

6 804 kg (15,000 lbs)

4 853 kg (10,700 lbs)

7 257 kg (16,000 lbs)

4 808 kg (10,600 lbs)

7 257 kg (16,000 lbs)

2 132 kg (4,700 lbs) 3 039 kg (6,700 lbs) 2 812 kg (6,200 lbs) 3 130 kg (6,900 lbs)

4 536 kg (10,000 lbs) 5 443 kg (12,000 lbs) 5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs)

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Vehicle 5.3L V8 (LC9) XFE 5.3L V8 (LMG) K5L HD Cooling Pkg 6.2L V8 K5L HD Cooling Pkg 6.2L V8 NHT Max Trailering Pkg

1500 Series 2WD Regular Cab Long Box

4.3L V6 (b) 4.3L V6 (b) 4.8L V8 (b) 4.8L V8 (b) 5.3L V8
5.3L V8 K5L HD Cooling Pkg 5.3L V8 K5L HD Cooling Pkg — Conventional Trailer 5.3L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer

Driving and Operating

9-77

Axle Ratio

Maximum Trailer Weight

GCWR (a)

3.08
3.42

3.42
3.73

3.23
3.73
3.23
3.73
3.08
3.08
3.42

3.42

3 175 kg (7,000 lbs) 4 355 kg (9,600 lbs)

5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs)

4 400 kg (9,700 lbs) 4 808 kg (10,600 lbs)

6 804 kg (15,000 lbs) 7 257 kg (16,000 lbs)

2 132 kg (4,700 lbs) 2 359 kg (5,200 lbs) 2 313 kg (5,100 lbs) 3 221 kg (7,100 lbs) 2 948 kg (6,500 lbs) 3 266 kg (7,200 lbs) 4 536 kg (10,000 lbs)

4 309 kg (9,500 lbs) 4 536 kg (10,000 lbs) 4 536 kg (10,000 lbs) 5 443 kg (12,000 lbs) 5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs)

4 037 kg (8,900 lbs)

6 804 kg (15,000 lbs)

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Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

1500 Series 2WD Extended Cab Long Box

5.3L V8 (b) 5.3L V8 K5L HD Cooling Pkg (b) 5.3L V8 K5L HD Cooling Pkg — Conventional Trailer 5.3L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer

1500 Series 4WD Regular Cab Standard Box

4.3L V6 (b) 4.8L V8 (b) 5.3L V8 (b) 5.3L V8 K5L HD Cooling Pkg 5.3L V8 K5L HD Cooling Pkg — Conventional Trailer 5.3L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer

3.08
3.08
3.42

3.42

3.73
3.42
3.08
3.08
3.42

3.42

2 722 kg (6,000 lbs) 3 039 kg (6,700 lbs) 4 309 kg (9,500 lbs)

5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs)

4 082 kg (9,000 lbs)

6 804 kg (15,000 lbs)

2 313 kg (5,100 lbs) 2 722 kg (6,000 lbs) 2 903 kg (6,400 lbs) 3 221 kg (7,100 lbs) 4 037 kg (8,900 lbs)

4 536 kg (10,000 lbs) 4 990 kg (11,000 lbs) 5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs) 6 350 kg (14,000 lbs)

3 719 kg (8,200 lbs)

6 350 kg (14,000 lbs)

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Driving and Operating

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Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

1500 Series 4WD Extended Cab Standard Box

4.8L V8 (b) 5.3L V8 (b) 5.3L V8 K5L HD Cooling Pkg (b) 5.3L V8 K5L HD Cooling Pkg — Conventional Trailer 5.3L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer 6.2L V8 K5L HD Cooling Pkg — Conventional Trailer 6.2L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer 6.2L V8 NHT Max Trailering Pkg — Conventional Trailer 6.2L V8 NHT Max Trailering Pkg — Fifth-Wheel Trailer

1500 Series 4WD Crew Cab Short Box (b)

4.8L V8
5.3L V8

3.42
3.08
3.08
3.42

3.42

3.42

3.42

3.73

3.73

3.42
3.08

2 495 kg (5,500 lbs) 2 767 kg (6,100 lbs) 3 084 kg (6,800 lbs) 4 354 kg (9,600 lbs)

4 990 kg (11,000 lbs) 5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs)

4 354 kg (9,600 lbs)

6 804 kg (15,000 lbs)

4 264 kg (9,400 lbs)

6 804 kg (15,000 lbs)

4 128 kg (9,100 lbs)

6 804 kg (15,000 lbs)

4 717 kg (10,400 lbs)

7 257 kg (16,000 lbs)

4 672 kg (10,300 lbs)

7 257 kg (16,000 lbs)

2 495 kg (5,500 lbs) 2 722 kg (6,000 lbs)

4 990 kg (11,000 lbs) 5 216 kg (11,500 lbs)

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Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

5.3L V8 K5L HD Cooling Pkg 5.3L V8 K5L HD Cooling Pkg 6.2L V8 K5L HD Cooling Pkg 6.2L V8 NHT Max Trailering Pkg

1500 Series 4WD Regular Cab Long Box

4.3L V6 (b) 4.8L V8 (b) 5.3L V8 (b) 5.3L V8 K5L HD Cooling Pkg 5.3L V8 K5L HD Cooling Pkg — Conventional Trailer 5.3L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer

1500 Series 4WD Extended Cab Long Box

5.3L V8 (b) 5.3L V8 K5L HD Cooling Pkg (b) 5.3L V8 K5L HD Cooling Pkg — Conventional Trailer

3.08
3.42
3.42
3.73

3.73
3.42
3.08
3.08
3.42

3.42

3.08
3.08
3.42

3 039 kg (6,700 lbs) 4 309 kg (9,500 lbs) 4 264 kg (9,400 lbs) 4 717 kg (10,400 lbs)

2 223 kg (4,900 lbs) 2 631 kg (5,800 lbs) 2 858 kg (6,300 lbs) 3 175 kg (7,000 lbs) 4 445 kg (9,800 lbs)

5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs) 6 804 kg (15,000 lbs) 7 257 kg (16,000 lbs)

4 536 kg (10,000 lbs) 4 990 kg (11,000 lbs) 5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs)

4 400 kg (9,700 lbs)

6 804 kg (15,000 lbs)

2 631 kg (5,800 lbs) 2 948 kg (6,500 lbs) 4 218 kg (9,300 lbs)

5 216 kg (11,500 lbs) 5 534 kg (12,200 lbs) 6 804 kg (15,000 lbs)

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Driving and Operating

9-81

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

5.3L V8 K5L HD Cooling Pkg — Fifth-Wheel Trailer

3.42

3 674 kg (8,100 lbs)

6 804 kg (15,000 lbs)

2500 Series 2WD Extended Cab Standard Box HD 3.73
4.10
4.10

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

2500 Series 2WD Crew Cab Standard Box HD

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

2500 Series 2WD Regular Cab Long Box HD

6.0L V8
6.0L V8 — Payload Performance Pkg (UB7) 6.0L V8 — Conventional Trailer 6.0L V8 — Fifth-Wheel Trailer

2500 Series 2WD Extended Cab Long Box HD

6.0L V8

3.73
4.10
4.10

3.73
3.73

4.10
4.10

3.73

4 445 kg (9,800 lbs) 5 897 kg (13,000 lbs) 6 486 kg (14,300 lbs)

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

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

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

4 627 kg (10,200 lbs) 4 536 kg (10,000 lbs)

7 257 kg (16,000 lbs) 7 257 kg (16,000 lbs)

5 897 kg (13,000 lbs) 6 668 kg (14,700 lbs)

9 299 kg (20,500 lbs) 9 299 kg (20,500 lbs)

4 400 kg (9,700 lbs)

7 257 kg (16,000 lbs)

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Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

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

4.10
4.10

5 897 kg (13,000 lbs) 6 441 kg (14,200 lbs)

9 299 kg (20,500 lbs) 9 299 kg (20,500 lbs)

2500 Series 2WD Crew Cab Long Box HD

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

3.73
4.10
4.10
2500 Series 4WD Extended Cab Standard Box HD 3.73
4.10
4.10

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

2500 Series 4WD Crew Cab Standard Box HD

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

2500 Series 4WD Regular Cab Long Box HD

6.0L V8
6.0L V8 — Conventional Trailer

3.73
4.10
4.10

3.73
4.10

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

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

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

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

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

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

4 491 kg (9,900 lbs) 5 897 kg (13,000 lbs)

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

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Driving and Operating

9-83

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

6.0L V8 — Fifth-Wheel Trailer

2500 Series 4WD Extended Cab Long Box HD

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

2500 Series 4WD Crew Cab Long Box HD

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

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

4.10

3.73
4.10
4.10

3.73
4.10
4.10

4.10

4.10

3.73
4.10

6 532 kg (14,400 lbs)

9 299 kg (20,500 lbs)

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

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

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

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

5 897 kg (13,000 lbs)

9 299 kg (20,500 lbs)

6 577 kg (14,500 lbs)

9 299 kg (20,500 lbs)

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

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

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9-84

Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

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

3500 Series 2WD Extended Cab Long Box

4.10

6 441 kg (14,200 lbs)

9 299 kg (20,500 lbs)

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

3.73
4.10

4.10

3.73

3.73

4.10

4.10

3.73
4.10

4 309 kg (9,500 lbs) 5 897 kg (13,000 lbs)

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

6 350 kg (14,000 lbs)

9 299 kg (20,500 lbs)

4 128kg (9,100 lbs)

7 257 kg (16,000 lbs)

4 173kg (9,200 lbs)

7 257 kg (16,000 lbs)

6 169 kg (13,600 lbs)

9 299 kg (20,500 lbs)

6 214 kg (13,700 lbs)

9 299 kg (20,500 lbs)

4 309kg (9,500 lbs) 5 897 kg (13,000 lbs)

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

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Driving and Operating

9-85

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

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 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)

4.10

3.73
4.10

4.10

3.73
4.10

3.73
4.10

4.10

3.73
4.10

6 350 kg (14,000 lbs)

9 299 kg (20,500 lbs)

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

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

6 305 kg (13,900 lbs)

9 299 kg (20,500 lbs)

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

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

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

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

6 441 kg (14,200 lbs)

9 299 kg (20,500 lbs)

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

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

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9-86

Driving and Operating

Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

3500 Series 4WD Extended 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) 6.0L V8 (Single Rear Wheels) Conventional Trailer 6.0L V8 (Single Rear Wheels) Fifth-Wheel Trailer

3.73
4.10

4.10

3.73
4.10

3.73
4.10
4.10

3.73
4.10

4.10

4 173 kg (9,200 lbs) 5 897 kg (13,000 lbs)

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

6 214 kg (13,700 lbs)

9 299 kg (20,500 lbs)

4 037 kg (8,900 lbs) 6 078 kg (13,400 lbs)

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

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

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

4 128 kg (9,100 lbs) 5 897 kg (13,000 lbs)

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

6 169 kg (13,600 lbs)

9 299 kg (20,500 lbs)

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Vehicle

Axle Ratio

Maximum Trailer Weight

GCWR (a)

Driving and Operating

9-87

6.0L V8 (Dual Rear Wheels) 6.0L V8 (Dual Rear Wheels)

7 257 kg (16,000 lbs) 9 299 kg (20,500 lbs) (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 lbs) 5 987 kg (13,200 lbs)

3.73
4.10

can tow. See “ Vehicle Load Limits” for more information about the vehicle's maximum load capacity.

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

Ask your dealer for trailering information or advice. Weight of the Trailer Tongue The tongue load (A) 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

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9-88

Driving and Operating

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) 499 kg (1,100 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 for more information.

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. 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 drivers door or see Vehicle Load Limits on page 9‑15 for more information. 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.

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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.

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 9‑73 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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Black plate (90,1)

9-90

Driving and Operating

Weight Distributing Hitch

Vehicle Series

1500

1500
1500
2500/3500

Trailer Weight Up to 7000 lbs

7001 to 9900 lbs

Over 9900 lbs Up to 18000 lbs

Usage Optional

Required Required Optional

Hitch Distribution

Refer to trailer manufacturer’s recommendation

50% 100%

Refer to trailer manufacturer’s recommendation

B. Front of Vehicle When using a weight-distributing hitch, measure distance (A) before coupling the trailer to the hitch ball. If the hitch requires 50% distribution, measure the height again after the trailer is coupled and adjust the spring bars so the distance (A) is as close as possible to halfway between the two measurements. When 100% distribution is required the spring bars should be adjusted so the distance (A) is the same as the

initial measurement after coupling the trailer to the tow vehicle and adjusting the hitch. 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.

A. Body to Ground Distance

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Black plate (91,1)

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 9‑73 for more information. 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 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 six inches 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.

Driving and Operating

9-91

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 lbs) with a factory-installed 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 lbs) 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 the vehicle has this provision, this relay will be located 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. Notice: 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

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9-92

Driving and Operating

exceeds the maximum amperage rating of 40 amperes 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.

Basic Trailer Wiring All regular, extended 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. If towing a light-duty trailer with a standard four-way round pin connector, an adapter is available from your dealer.

Heavy-DutyTrailer 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: . Yellow: Left Stop/Turn Signal . Dark Green: Right Stop/Turn

Signal

. Brown: Taillamps . White: Ground

Light Green: Back-up Lamps

. Red: Battery Feed* . Dark Blue: Trailer Brake* *The fuses for these two circuits are installed in the underhood electrical center, but the wires are not connected. They should be connected by your dealer or a qualified service center. The fuse and wire for the ITBC is factory installed and connected if the vehicle is equipped with an ITBC. The fuse for the battery feed is not required if the vehicle has an auxiliary battery. If the vehicle does not have an auxiliary battery, have your dealer or authorized service center install the required fuse. 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

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Black plate (93,1)

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 located under the front edge of the pickup box on the driver side of the vehicle, attached to the frame bracket. A connector must be added to the wiring harness which connects to the camper. The harness contains the following camper/trailer circuits: . Yellow: Left Stop/Turn Signal . Dark Green: Right Stop/Turn

Signal

. Brown: Taillamps . White: Ground

Light Green: Back-up Lamps

. Red: Battery Feed . Dark Blue: Trailer Brake

If the vehicle is equipped with the “Heavy-Duty Trailering” option, please refer to “Heavy-Duty Trailer Wiring 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 located at the rear of the vehicle and is tied to the vehicle's frame.

Driving and Operating

9-93

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 instrument panel contains blunt cut wires behind the steering column for the trailer brake controller. The harness contains the following wires: . Dark Blue: Brake Signal to

Trailer Connector

. Red/Black: Battery

Light Blue/White: Brake Switch

. White: Ground The harness should be installed by your dealer or a qualified service center. If the vehicle is equipped with an Integrated Trailer Brake Control (ITBC) System, the blunt cuts exist, but are not connected further in the harness. If an aftermarket trailer brake controller is installed, the

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Black plate (94,1)

9-94

Driving and Operating

ITBC must be disconnected. Do not power both ITBC and aftermarket controllers to control the trailer brakes at the same time. Tow/Haul Mode

This indicator light on the instrument panel 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 9‑37 for more information. 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 9‑73. Tow/ Haul is most useful under the following driving conditions: . When pulling a heavy trailer or a

large or heavy load through rolling terrain.

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

. 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.

Operating the vehicle in Tow/Haul when lightly loaded or with no trailer at all will not cause damage. However, there is no benefit to the selection of Tow/Haul when the vehicle is unloaded. Such a selection when unloaded may result in unpleasant engine and transmission driving characteristics and reduced fuel economy. Tow/ Haul is recommended only when pulling a heavy trailer or a large or heavy load.

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Black plate (95,1)

Driving and Operating

9-95

Integrated Trailer Brake Control System

The vehicle may have an Integrated Trailer Brake Control (ITBC) system for electric trailer brakes. This symbol is located on the Trailer Brake Control Panel on vehicles with an Integrated Trailer Brake Control system. The power output to the trailer brakes is based on the amount of brake pressure being applied by the vehicle’s brake system. This available power output to the trailer brakes can be adjusted to a wide range of trailering situations. The ITBC system is integrated with the vehicle’s brake, antilock brake, and StabiliTrak (if equipped) systems. In trailering conditions that

cause the vehicle’s antilock brake or StabiliTrak systems to activate, power sent to the trailer's brakes will be automatically adjusted to minimize trailer wheel lock-up. This does not imply that the trailer has StabiliTrak. The vehicle may have a Trailer Sway Control (TSC) feature. See Trailer Sway Control (TSC) on page 9‑100. The vehicle may have a Hill Start Assist (HSA) feature. See Hill Start Assist (HSA) on page 9‑52. If the vehicle’s brake, antilock brake, or StabiliTrak systems are not functioning properly, the ITBC system may not be fully functional or may not function at all. Make sure all of these systems are fully operational to ensure full functionality of the ITBC system. The ITBC system is powered through the vehicle's electrical system. Turning the ignition off will also turn off the ITBC system. The

ITBC system is fully functional only when the ignition is in ON or in RUN. The ITBC system can only be used with trailers with electric brakes.

{ WARNING

Connecting a trailer that has a surge, air, or electric-over-hydraulic trailer brake system may result in reduced or complete loss of trailer braking. There may be an increase in stopping distance or