2004 GMC ENVOY XL Owners Manual

Temperature – A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation
of heat and its ability to dissipate heat when tested
under controlled conditions on a specied indoor
laboratory test wheel. Sustained high temperature can
cause the material of the tire to degenerate and
reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a
level of performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inated and not
overloaded. Excessive speed, underination, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are
not needed. However, if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
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.
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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.
SeeChanging a Flat Tire on page 5-74for 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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Tire Chains
{CAUTION:
Don’t use tire chains. There’s not enough
clearance. Tire chains used on a vehicle without
the proper amount of clearance can cause
damage to the brakes, suspension or other
vehicle parts. The area damaged by the tire
chains could cause you to lose control of your
vehicle and you or others may be injured in a
crash. Use another type of traction device only
if its manufacturer recommends it for use on
your vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it’s contacting your vehicle, and don’t
spin your wheels. If you do nd traction devices
that will t, install them on the rear tires.
Accessory Inator
Your vehicle may be equipped with an air inator
system. You can inate things like basketballs and
bicycle tires. Also, you can use it to bring your tire
pressure up to the proper pressure. It is not designed
to inate large objects which will require more than ve
minutes to inate, such as an air mattress.
The air inator is
located in the rear
compartment on the
passenger’s side of
the vehicle behind
an access cover.
To remove the cover, pull the two tabs on the cover
and pull it off.
The air inator kit includes a 22 ft (6.7 m) hose with
three nozzle adapters.
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To use the air inator, attach the appropriate nozzle
adapter to the end of the hose if required. Then attach
that end of the hose to the object you wish to inate.
Attach the other end of the hose to the outlet.
Press and release the switch to turn the air inator on.
The indicator light will remain on when the inator is
running.
The system has an internal clock to prevent overheating.
The system will allow about ve minutes of running
time, then the compressor will stop. The indicator light
will then begin to ash. When the indicator is off,
the inator can be started again by pressing the switch.
If the compressor is still hot, it may only run for a
short time before shutting off again.
Press and release the switch to turn the inator off.
Place the inator kit tools in the pouch and store
it properly. Remove the inator hose from the outlet
during loading and unloading. Load leveling will
not function with the inator hose attached to the inator
outlet. See “Electronically Controlled Air Suspension
System” underLoading Your Vehicle on page 4-49
for more information.To reinstall the cover, line up the tabs at the back of the
cover, put it in place and latch the tabs.
A continuous ashing indicator light may also indicate
a malfunction in the air suspension system. See
“Electronically Controlled Air Suspension System” under
Loading Your Vehicle on page 4-49for more information.
{CAUTION:
Inating something too much can make it
explode, and you or others could be injured.
Be sure to read the inator instructions, and
inate any object only to its recommended
pressure.
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If a Tire Goes Flat
It’s unusual for a tire to “blowout” while you’re driving,
especially if you maintain your tires properly. If air goes
out of a tire, it’s much more likely to leak out slowly.
But if you should ever have a “blowout,” here are a
few tips about what to expect and what to do:
If a front tire fails, the at tire will create a drag that
pulls the vehicle toward that side. Take your foot off
the accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake
to a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like
a skid and may require the same correction you’d use
in a skid. In any rear blowout, remove your foot from
the accelerator pedal. Get the vehicle under control
by steering the way you want the vehicle to go. It may
be very bumpy and noisy, but you can still steer.
Gently brake to a stop, well off the road if possible.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is designed
only for changing a at tire. If it is used for
anything else, you or others could be badly
injured or killed if the vehicle slips off the jack.
Use the jack provided with your vehicle only
for changing a at tire.
If a tire goes at, the next part shows how to use your
jacking equipment to change a at tire safely.
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Changing a Flat Tire
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your hazard
warning ashers.
{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
3. If you have a four-wheel-drive vehicle,
be sure the transfer case is in a drive
gear – not in NEUTRAL.
4. Turn off the engine and do not restart
while the vehicle is raised.
5. Do not allow passengers to remain in
the vehicle.
CAUTION: (Continued)
CAUTION: (Continued)
6. Put the wheel blocks at the front and
rear of the tire farthest away from the
one being changed. That would be the
tire on the other side, at the opposite
end of the vehicle.
The following steps will tell you how to use the jack
and change a tire.
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Removing the Spare Tire and Tools
The jacking equipment you will need is stored under the
rear seat in the Envoy or in the left rear quarter panel
storage compartment in the Envoy XL. To release
the jack from its holder, turn the knob on the jack
counterclockwise to lower the jack head. SeeRear Seat
Operation on page 1-5 Envoy
Envoy XL
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The tools you’ll be using include the wheel wrench (A),
wheel blocks (B), extension(s) (socket end) (C),
handle (jack end) (D), and jack (E).
The following instructions explain how to remove the
spare tire mounted underneath your vehicle.
Notice:If you remove or restow a tire from/to the
storage position under the vehicle when it is
supported by a jack, you could damage the tire
and/or your vehicle. Always remove or restow a
tire when the vehicle is on the ground.1. To remove the underbody-mounted spare, insert
the socket end of the extension on a 45° angle
downward into the hoist drive shaft hole. It is
exposed when the rear gate is open and is just
above the rear bumper. Be sure the socket end of
the extension connects to the hoist shaft.
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