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Vehicle* Axle Ratio Maximum Trailer Weight GCWR
K-3500 Regular Cab (4WD)
6000 V8 Dual Rear
Wheel4.10 9,800 lbs (4 445 kg) 16,000 lbs (7 257 kg)
6000 V8 Single Rear
Wheel4.10 10,000 lbs (4 536 kg) 16,000 lbs (7 257 kg)
8100 V8 Dual Rear
Wheel4.10 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
8100 V8 Single Rear
Wheel4.10 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
6.6L V8 Dual Rear
Wheel (Auto)3.73 12,000 lbs (5 443 kg) 23,500 lbs (10 659 kg)
6.6L V8 Dual Rear
Wheel (Manual)3.73 12,000 lbs (5 443 kg) 23,500 lbs (10 659 kg)
6.6L V8 Single Rear
Wheel3.73 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
K-3500 Extended Cab (4WD)*
6000 V8 Dual Rear
Wheel4.10 9,400 lbs (4 264 kg) 16,000 lbs (7 257 kg)
6000 V8 Single Rear
Wheel4.10 9,600 lbs (4 354 kg) 16,000 lbs (7 257 kg)
8100 V8 Dual Rear
Wheel4.10 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
8100 V8 Single Rear
Wheel4.10 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
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Vehicle* Axle Ratio Maximum Trailer Weight GCWR
6.6L V8 Diesel Dual
Rear Wheel (Manual)3.73 12,000 lbs (5 443 kg) 23,500 lbs (10 659 kg)
6.6L V8 Diesel Dual
Rear Wheel (Auto)3.73 12,000 lbs (5 443 kg) 23,500 lbs (10 659 kg)
6.6L V8 Diesel Single
Rear Wheel3.73 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
* Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,500 lbs
(1 587 kg) maximum.
Vehicle* Axle Ratio Maximum Trailer Weight GCWR
K-3500 Crew Cab (4WD)*
6000 V8 Dual Rear
Wheel4.10 9,100 lbs (4 128 kg) 16,000 lbs (7 264 kg)
6000 V8 Single Rear
Wheel4.10 9,400 lbs (4 264 kg) 16,000 lbs (7 264 kg)
8100 V8 Dual Rear
Wheel4.10 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
8100 V8 Single Rear
Wheel4.10 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
6.6L V8 Diesel Single
Rear Wheel (Auto)3.73 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
6.6L V8 Diesel Single
Rear Wheel (Manual)3.73 12,000 lbs (5 443 kg) 22,000 lbs (9 979 kg)
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Vehicle* Axle Ratio Maximum Trailer Weight GCWR
6.6L V8 Diesel Dual
Rear Wheel (Auto)3.73 12,000 lbs (5 443 kg) 23,500 lbs (10 659 kg)
6.6L V8 Diesel Dual
Rear Wheel (Manual)3.73 12,000 lbs (5 443 kg) 23,500 lbs (10 659 kg)
*Fifth-wheel or gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,500 lbs
(1 587 kg) maximum.
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 your vehicle
should not be exceeded.You can ask your dealer for our trailering information or
advice, or you can write us at the address listed in
your Warranty and Owner Assistance Information
Booklet.
In Canada, write to:
General Motors of Canada Limited
Customer Communications Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
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Page 380 of 580

Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight
of your vehicle. The Gross Vehicle Weight (GVW)
includes the curb weight of the vehicle, any cargo you
may carry in it, and the people who will be riding in
the vehicle. If you have a lot of options, equipment,
passengers or cargo in your vehicle, it will reduce the
tongue weight your vehicle can carry, which will
also reduce the trailer weight your vehicle can tow. And
if you will tow a trailer, you must add the tongue load
to the GVW because your vehicle will be carrying
that weight, too. SeeLoading Your Vehicle on page 4-50
for more information about your vehicle’s maximum
load capacity.The trailer tongue weight (A) should be 10 percent to
15 percent of the total loaded trailer weight, up to a
maximum of 600 lbs (272 kg) for the 1500 or 2500 series,
and up to a maximum of 750 lbs (340 kg) for the 2500 HD
or 3500 series with a weight carrying hitch. The trailer
tongue weight (A) should be 10 percent to 15 percent of
the total loaded trailer weight, up to a maximum of
1,000 lbs (453 kg) for the 1500 series and up to a
maximum of 1,500 lbs (680 kg) for the 2500, 2500 HD or
3500 series with a weight distributing hitch.
Fifth wheel or gooseneck kingpin weight should be
15 to 25 percent of the trailer weight up to the maximum
amount speci ed in the trailering chart for your vehicle.
See “Weight of theTrailer”, and “Fifth-Wheel and
Gooseneck Trailering” in this section.
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Do not exceed the maximum allowable tongue weight
for your 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.
After you have loaded the trailer, weigh the trailer and
then the tongue separately, to see if the weights
are proper. If they are not, you may be able to get them
right by moving some items around in the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are in ated to the upper limit
for cold tires. You’ll nd these numbers on the
Certi cation label at the rear edge of the driver’s door or
see Loading Your Vehicle for more information. Then
be sure you don’t go over the GVW limit for your vehicle,
or the GAWR, including the weight of the trailer
tongue. If you use a weight distributing hitch, make sure
you don’t go over the rear axle limit before you apply
the weight distribution spring bars.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are
a few reasons why you’ll need the right hitch.
Weight-Distributing Hitches and Weight
Carrying Hitches
A:Body to Ground Distance
B:Front of Vehicle
When using a weight-distributing hitch, the hitch must
be adjusted so the distance (A) remains the same both
before and after coupling the trailer to the tow vehicle.
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If you use a step-bumper hitch, 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.
If you will be pulling a trailer that, when loaded, will
weigh more than 5,000 lbs (2 270 kg) be sure to use a
properly mounted weight-distributing hitch and sway
control of the proper size. This equipment is very
important for proper vehicle loading and good handling
when driving. Always use a sway control if the trailer
will weigh more than these limits. You can ask a
hitch dealer about sway controls.
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 speci ed in the trailering chart for your vehicle.
See “Weight of the Trailer” in this section for more
information.
The hitch should be located in the pickup bed so that it’s
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
fth 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.
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Safety Chains
You should always attach chains between your vehicle
and your 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 you are towing a trailer up to 5,000 lbs
(2 271 kg) with a factory-installed step bumper, you
may attach the safety chains to the attaching points on
the bumper. If you are towing a trailer up to your
vehicle’s trailer rating limit you may attach the safety
chains to the attaching point on the hitch platform. If you
are towing with an aftermarket hitch follow the trailer
or hitch manufacturer’s recommendation for attaching
safety chains. Always leave just enough slack so
you can turn with your rig. Never allow safety chains to
drag on the ground.
Trailer Brakes
If your trailer weighs more than 2,000 lbs (900 kg)
loaded, then it needs its own brakes – and they must be
adequate. Be sure to read and follow the instructions
for the trailer brakes so you’ll be able to install,
adjust and maintain them properly.
Your trailer brake system can tap into the vehicle’s
hydraulic brake system only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of uid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
If everything checks out this far, make the brake tap at
the port on the master cylinder that sends the uid
to the rear brakes. But don’t use copper tubing for this.
If you do, it will bend and nally break off. Use steel
brake tubing.
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Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You cannot see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-56. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. SeeClimate Control System
on page 3-20.Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
While towing a trailer or when exposed to long periods
of sunshine, the oor of the truck bed may become
very warm. Avoid putting items in the truck bed
that might be affected by high ambient temperatures.
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