ground clearance GMC SIERRA 2007 Owner's Manual

If you think you will need some more ground
clearance at the front of your vehicle, you
can remove the front fascia lower air dam.
The front fascia lower air dam is held in place by
two bolts and 10 snap features. The bolts and
snap features are accessible from underneath the
front fascia.
The following steps must be performed on the
bolts and snap features to remove the air dam:
1. Remove the two outboard air dam bolts.
2. With a at-blade screwdriver, push down on
the snap features and disengage the snaps.
3. After the bolts are removed and the snaps are
disengaged, push forward on the air dam until
it is free.
When you are back on roads, though, be sure to
replace the air dam.
Notice:Operating your vehicle for extended
periods without the front fascia lower air
dam installed can cause improper air ow to
the engine. Always be sure to replace the front
fascia air dam when you are nished off-road
driving.To reinstall the lower air dam do the following:
1. Line up the snap features and push the
air dam rearward to engage the snaps.
2. Install the two outboard bolts.
Before You Go Off-Roading
There are some things to do before you go out.
For example, be sure to have all necessary
maintenance and service work done. Check to
make sure all underbody shields, if the vehicle has
them, are properly attached. Be sure you read
all the information about your four-wheel-drive
vehicle in this manual. Is there enough fuel? Is the
spare tire fully inated? Are the uid levels up
where they should be? What are the local
laws that apply to off-roading where you will be
driving? If you do not know, you should check with
law enforcement people in the area. Will you be
on someone’s private land? If so, be sure to
get the necessary permission.
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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.
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.
If your vehicle is equipped with StabiliTrak
®,
your trailer cannot tap into the vehicle’s hydraulic
brake system.
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Wheel Replacement
Replace any wheel that is bent, cracked, or badly
rusted or corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts and wheel nuts
should be replaced. If the wheel leaks air, replace
it (except some aluminum wheels, which can
sometimes be repaired). See your dealer if any of
these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same
load-carrying capacity, diameter, width, offset
and be mounted the same way as the one
it replaces.
If you need to replace any of your wheels, wheel
bolts or wheel nuts, replace them only with
new GM original equipment parts. This way, you
will be sure to have the right wheel, wheel
bolts and wheel nuts for your vehicle.{CAUTION:
Using the wrong replacement wheels,
wheel bolts, or wheel nuts on your vehicle
can be dangerous. It could affect the
braking and handling of your vehicle,
make your tires lose air and make you
lose control. You could have a collision in
which you or others could be injured.
Always use the correct wheel, wheel bolts,
and wheel nuts for replacement.
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.
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