2004 GMC SIERRA ground clearance

Off-Road Driving with Your
Four-Wheel-Drive Vehicle
This off-road guide is for vehicles that have four-wheel
drive. Also, seeBraking on page 4-6. If your vehicle
does not have four-wheel drive, you should not
drive off-road unless you are on a level, solid surface.
Off-road driving can be great fun. But it does have some
de®nite hazards. The greatest of these is the terrain
itself.
ªOff-roadingº means you have left the great North
American road system behind. Traffic lanes are not
marked. Curves are not banked. There are no
road signs. Surfaces can be slippery, rough, uphill or
downhill. In short, you have gone right back to nature.
Off-road driving involves some new skills. And that
is why it is very important that you read this guide. You
will ®nd many driving tips and suggestions. These
will help make your off-road driving safer and more
enjoyable.
If you think you will need some more ground clearance
at the front of your vehicle, you can easily remove
the front bumper lower air dam.
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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 ªWeight of the Trailerº 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.
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.
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Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance and tire or tire chain
clearance to the body and chassis.
Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque
after 100, 1,000 and 6,000 miles (160, 1 600 and
10 000 km) of driving. For proper torque, see ªWheel Nut
Torqueº under
Capacities and Speci®cations on
page 5-134.
See
Changing a Flat Tire on page 5-96for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used
or how far it's been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
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