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4-31 If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live but
also where you'll be driving. A good source for this
information can be state or provincial police.
Don't tow a trailer at all during the first 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the first 500 miles (800 km) that you
tow a trailer, don't drive over 50 mph (80 km/h) and
don't make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at the
heavier loads.
If you have an automatic transmission, you can tow
in OVERDRIVE (). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
If you have a manual transmission and you are
towing a trailer, it's better not to use the highest gear.Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle's tires.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig.
For example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to
pull a trailer are all important. And, it can also depend
on any special equipment that you have on your vehicle.
Use the following chart to determine how much your
vehicle and trailer can weigh, based upon your vehicle
model and options.
3500HD models are incomplete vehicles and trailer
ratings are not assigned. Use the Gross Combination
Weight Rating (GCWR) chart to determine the
combination weight limit.
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4-32
Maximum trailer weight is calculated by subtracting
the weight of your completed vehicle from the GCWR.
The weight of the completed vehicle, passengers, cargo
in the tow vehicle and the loaded trailer weight must not
exceed the GCWR.
Refer to the Trailering Guide for oil cooler
recommendations.
EngineAxle
RatioGross Combination
Weight Rating
6.5L Diesel 4.63 17,000 lbs. (7 718 kg)
5.13 17,000 lbs. (7 718 kg)
8.1L 4.63 19,000 lbs. (8 626 kg)
5.13 19,000 lbs. (8 626 kg)
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 Communication Centre, 163
-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
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. 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. See ªLoading
Your Vehicleº in the Index for more information about
your vehicle's maximum load capacity.
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4-33
If you're using a weight-carrying or a weight-distributing
hitch, the trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight (B).
Do not exceed the maximum allowable tongue weight
for your vehicle.
After you've loaded your trailer, weigh the trailer and
then the tongue, separately, to see if the weights are
proper. If they aren't, you may be able to get them
right simply by moving some items around in the trailer.
Total Weight on Your Vehicle's Tires
Be sure your vehicle's tires are inflated to the upper
limit for cold tires. You'll find these numbers on the
Certification/Tire label at the rear edge of the driver's
door or see ªTire Loadingº in the Index. Then be
sure you don't go over the GVW limit for your vehicle,
including the weight of the trailer tongue.
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.
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.
Follow the 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.
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4-34 Trailer Brakes
If your trailer weighs more than 1,000 lbs. (450 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 fluid 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 fluid to
the rear brakes. But don't use copper tubing for this.
If you do, it will bend and finally break off. Use steel
brake tubing.
Driving with a Trailer
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 the trailer hitch and platform
(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.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require heavy
braking and sudden turns.
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6-10
Noise Control System
The following information relates to compliance with
federal noise emission standards for vehicles with a Gross
Vehicle Weight Rating (GVWR) of more than 10,000 lbs.
(4 536 kg). The Maintenance Schedule provides
information on maintaining the noise control system
to minimize degradation of the noise emission control
system during the life of your vehicle. The noise control
system warranty is given in your warranty booklet.
These standards apply only to vehicles sold in the
United States.
Tampering With Noise Control
System Prohibited
Federal law prohibits the following acts or the
causing thereof:
1. The removal or rendering inoperative by any person,
other than for purposes of maintenance, repair or
replacement, of any device or element of design
incorporated into any new vehicle for the purpose
of noise control, prior to its sale or delivery to
the ultimate purchaser or while it is in use; or
2. The use of the vehicle after such device or element
of design has been removed or rendered inoperative
by any person.Among those acts presumed to constitute tampering are
the acts listed below.
Insulation:
Removal of the noise shields or any
underhood insulation.
Engine:
Removal or rendering engine speed governor
(if equipped) inoperative so as to allow engine
speed to exceed manufacturer specifications.
Fan and Drive:
Removal of fan clutch (if equipped) or rendering
clutch inoperative.
Removal of the fan shroud (if equipped).
Air Intake:
Removal of the air cleaner silencer.
Modification of the air cleaner.
Exhaust:
Removal of the muffler and/or resonator.
Removal of the exhaust pipes and exhaust pipe clamps.