tire size GMC ENVOY 2003 Owner's Manual

4. Shift the transfer case to NEUTRAL (N). See
ªFour-Wheel Driveº in the Index for the proper
procedure to select the NEUTRAL position for your
vehicle.
5. Release the parking brake only after the vehicle
being towed is ®rmly attached to the towing
vehicle.
6. Turn the ignition off and remove the key. If the key
is not removed, the battery will drain.
{CAUTION:
Shifting a four-wheel-drive vehicle's transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in Park (P). You
or others could be injured. Make sure the
parking brake is ®rmly set before you shift the
transfer case to NEUTRAL.
Dolly Towing
Your vehicle was not designed to be dolly towed. If you
need to tow your vehicle, see ªDinghy Towingº earlier
in this section.
Loading Your Vehicle
The Certi®cation/Tire label is found on the driver's door
edge, above the door latch. The label shows the
size of your original tires and the in¯ation pressures
needed to obtain the gross weight capacity of your
vehicle. This is called the Gross Vehicle Weight Rating
(GVWR). The GVWR includes the weight of the
vehicle, all occupants, fuel, cargo and trailer tongue
weight, if pulling a trailer.
The Certi®cation/Tire label also tells you the maximum
weights for the front and rear axles, called Gross
Axle Weight Rating (GAWR).
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When It Is Time for New Tires
One way to tell when it's
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining. Some
commercial truck tires may
not have treadwear
indicators.You need a new tire if any of the following statements
are true:·You can see the indicators at three or more places
around the tire.
·You can see cord or fabric showing through the
tire's rubber.
·The tread or sidewall is cracked, cut or snagged
deep enough to show cord or fabric.
·The tire has a bump, bulge or split.
·The tire has a puncture, cut or other damage that
can't be repaired well because of the size or
location of the damage.
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Buying New Tires
To ®nd out what kind and size of tires you need, look at
the Certi®cation/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Speci®cation (TPC Spec)
number on each tire's sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service on
your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by an ªMSº (for
mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires) the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim ¯anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
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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 In¯ator
Your vehicle may be equipped with an air in¯ator
system. You can in¯ate 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
in¯ate large objects which will require more than ®ve
minutes to in¯ate, such as an air mattress.
The air in¯ator is often
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.
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