1999 GMC C-SERIES tires

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Winter Driving
Here are some tips for winter driving:

Be sure the vehicle is in good shape for winter.

You may want to put winter emergency supplies in
your vehicle.Include an ice scraper, a small brush or broom, a supply
of windshield washer fluid, a rag, some winter outer
clothing, a small shovel, a flashlight, a red cloth and
reflective warning triangles. And, if you will be driving
under severe conditions, include a small bag of sand, a
piece of old carpet or a couple of burlap bags to help
provide traction. Be sure you properly secure these
items in your vehicle.
Driving on Snow or Ice
Most of the time, those places where your tires meet the
road probably have good traction.
However, if there is snow or ice between your tires and
the road, you can have a very slippery situation. You'll
have a lot less traction or ªgripº and will need to be
very careful.
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What's the worst time for this? ªWet ice.º Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offer the
least traction of all. You can get wet ice when it's about
freezing (32
F; 0
C) and freezing rain begins to fall.
Try to avoid driving on wet ice until salt and sand crews
can get there.Whatever the condition
-- smooth ice, packed, blowing
or loose snow
-- drive with caution.
Accelerate gently. Try not to break the fragile traction.
If you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Unless you have the anti
-lock braking system, you'll
want to brake very gently, too. (If you do have anti
-lock,
see ªAnti
-Lockº in the Index. This system improves
your vehicle's stability when you make a hard stop on a
slippery road.) Whether you have the anti
-lock braking
system or not, you'll want to begin stopping sooner than
you would on dry pavement. Without anti
-lock brakes,
if you feel your vehicle begin to slide, let up on the
brakes a little. Push the brake pedal down steadily to get
the most traction you can.
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If you have a diesel engine, you may have to run it at a
higher speed to get enough heat. Then, shut the engine
off and close the window almost all the way to preserve
the heat. Start the engine again and repeat this only
when you feel really uncomfortable from the cold. But
do it as little as possible. Preserve the fuel as long as you
can. To help keep warm, you can get out of the vehicle
and do some fairly vigorous exercises every half hour or
so until help comes.Loading Your Vehicle
The GVW/Tire Information label is found on the rear
edge of the driver's door. The label shows the size of
your original tires and the inflation 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 and cargo.
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If a Tire Goes Flat
It's unusual for a tire to ªblow outº 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 ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
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.
If a tire goes flat, the next part tells you what to do.
Changing a Flat Tire
A flat or damaged tire can be a major roadside problem.
You're very likely to have to go for help. Few drivers of
these vehicles have the necessary equipment aboard to
be able to change a flat tire safely. For example, youhave to have a truck jack that can lift several thousand
pounds and a torque wrench that can generate several
hundred foot
-pounds (newton-meters) of twisting force.
So if you're stopped somewhere by a flat or damaged
tire or wheel, you should get expert help right then.
If the correct equipment is available, though, here is the
procedure to follow.

Does the tire still seem to have air under pressure in
it? If so, stand to the side and look at the wheel. See
if it looks like another wheel on the vehicle. If so, go
on to the next step. If it doesn't, or even if you can't
be sure, stop and get expert help.
CAUTION:
Tire-rim assemblies can explode. If you work on
a pressurized tire mounted on a damaged wheel,
the assembly can expand with explosive force
without warning. You and others nearby can be
badly injured. Don't work around a tire that has
air under pressure in it when its wheel is or might
be damaged.
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If the wheel looks normal, see if the wheel has side
rings and a lock ring around the wheel rim. If so,
they must be seated properly. You can compare with
another wheel on the vehicle as you check for this.
For dual wheels, you have to look between the tires
to make this check. You may not be able to tell
if the side rings or lock rings are seated properly
by looking. If you can't be sure, stop and get
expert help.
CAUTION:
If you work on a pressurized tire mounted on a
damaged wheel, the assembly can expand with
explosive force without warning. You and others
nearby can be badly injured. Don't work around
a tire that has air under pressure in it when its
lock ring or side ring might not be
properly seated.
CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the wheel nuts
become loose after a time. The wheel could come
off and cause an accident. When you change a
wheel, remove any rust or dirt from the places
where the wheel attaches to the vehicle. In an
emergency, you can use a cloth or a paper towel
to do this; but be sure to use a scraper or wire
brush later, if you need to, to get all the rust or
dirt off.

If the lock ring and side rings seem to be seated
properly (or if the wheel doesn't have these), let the
air out of the tire. You can do this by taking out the
valve core.

If the flat or damaged tire is one of a dual set, let the
air out of both tires of the dual before you take off
the damaged tire and rim assembly.

If you have the correct equipment, put on the spare
wheel and tire assembly.
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CAUTION:
Never use oil or grease on studs or nuts. If you
do, the nuts might come loose. Your wheel could
fall off, causing a serious accident.
CAUTION:

There are many ways to be hurt badly, or
be killed, while you are trying to change a
truck tire and rim. Follow all of the safety
precautions on the truck jack and
other equipment.
CAUTION: (Continued)
CAUTION: (Continued)

If you try to put air back into a tire that has
run flat, or even a tire that was quite low on
air, without first finding out why it was low
or flat, the tire can have a sudden air
-out.
This could cause you to lose control of the
vehicle and have a serious crash. Don't
refill a flat or very low tire with air without
first having the tire taken off the wheel and
checked for damage.

Use a clip-on chuck and hose extension when you
add air to your tires. You'll need an accurate truck
tire pressure gage. Stand to one side and add the air.
Be sure you don't go over the top inflation pressure
for the tire.
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CAUTION:
Incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to become loose
and even come off. This could lead to an accident.
Be sure to use the correct wheel nuts. If you have
to replace them, be sure to get new GM original
equipment wheel nuts.
Stop somewhere as soon as you can and have the
nuts tightened with a torque wrench.
See ªTightening the Wheel Nutsº in the Index for
the proper torque for your particular wheel.
NOTICE:
Improperly tightened wheel nuts can lead to
brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque specification.
If You're Stuck: In Sand, Mud,
Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you don't want to spin your
wheels too fast. The method known as ªrockingº can
help you get out when you're stuck, but you must
use caution.
CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transmission or other parts of the vehicle can
overheat. That could cause an engine
compartment fire or other damage. When you're
stuck, spin the wheels as little as possible. Don't
spin the wheels above 35 mph (55 km/h) as shown
on the speedometer.
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NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth, you can destroy your transmission.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between REVERSE (R) and a forward gear
(or with a manual transmission, between FIRST (1) or
SECOND (2) and REVERSE (R)), spinning the wheels
as little as possible. Release the accelerator pedal while
you shift, and press lightly on the accelerator pedal
when the transmission is in gear. By slowly spinning
your wheels in the forward and reverse directions, you
will cause a rocking motion that may free your vehicle.
If that doesn't get you out after a few tries, you may
need to be towed out. If you do need to be towed out,
see ªTowing Your Vehicleº in the Index.
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