
Loss of Control
Let's review what driving experts say about what
happens when the three control systems (brakes,
steering and acceleration) don't have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, don't give up. Keep trying to steer
and constantly seek an escape route or area of
less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not
ªoverdrivingº those conditions. But skids are always
possible.
The three types of skids correspond to your vehicle's
three control systems. In the braking skid, your wheels
aren't rolling. In the steering or cornering skid, too much
speed or steering in a curve causes tires to slip and lose
cornering force. And in the acceleration skid, too much
throttle causes the driving wheels to spin.
A cornering skid is best handled by easing your foot off
the accelerator pedal.If you have the Traction Assist System, remember: It
helps avoid only the acceleration skid. If you do not have
this system, or if the system is off, then an acceleration
skid is also best handled by easing your foot off the
accelerator pedal.
If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle to go. If you start steering quickly enough,
your vehicle may straighten out. Always be ready
for a second skid if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety, you'll
want to slow down and adjust your driving to these
conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration
or braking (including engine braking by shifting to a
lower gear). Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your vehicle is skidding. Learn to recognize warning
clues Ð such as enough water, ice or packed snow
on the road to make a ªmirrored surfaceº Ð and slow
down when you have any doubt.
Remember: Any anti-lock brake system (ABS) helps
avoid only the braking skid.
4-21

·Tire overloading
·Bad wear
·Bad handling
·Bad fuel economy
If your tires have too much air (overin¯ation), you
can get the following:
·Unusual wear
·Bad handling
·Rough ride
·Needless damage from road hazards
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can't tell if your tires are properly in¯ated
simply by looking at them. Radial tires may look
properly in¯ated even when they're underin¯ated.Remove the valve cap from the tire valve stem. Press
the tire gage ®rmly onto the valve to get a pressure
measurement. If the cold tire in¯ation pressure is low,
add air until you reach the recommended amount.
If you over®ll the tire, release air by pushing on the metal
stem in the center of the tire valve. Recheck the tire
pressure with the tire gage.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel nut is replaced, 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 and wheel nut
tightening information, see ªRemoving the Flat Tire
and Installing the Spare Tireº in the index.
The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate the tires periodically.
See ªTire Inspection and Rotationº earlier in this
section. Also see ªScheduled Maintenance Servicesº in
the Index for scheduled rotation intervals
5-70

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
CAUTION: (Continued)
CAUTION: (Continued)
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.
If your vehicle has 20 inch road tires (those
originally installed on your vehicle) it is all
right to drive with the 16 inch spare tire that
came with your vehicle. When new, your
vehicle included a spare tire and wheel
assembly with the same overall diameter as
your vehicle's road tires and wheels. Because
this spare tire was developed for use on your
vehicle, it will not affect vehicle handling or
cause damage to your vehicle.
{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.
5-74

Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system developed
by the United States National Highway Traffic Safety
Administration, which grades tires by treadwear, traction
and temperature performance. (This applies only to
vehicles sold in the United States.) The grades are
molded on the sidewalls of most passenger car tires. The
Uniform Tire Quality Grading system does not apply to
deep tread, winter-type snow tires, space-saver or
temporary use spare tires, tires with nominal rim
diameters of 10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a speci®ed government test course. For
example, a tire graded 150 would wear one and a half
(1.5) times as well on the government course as a tire
graded 100. The relative performance of tires depends
upon the actual conditions of their use, however, and may
depart signi®cantly from the norm due to variations in
driving habits, service practices and differences in road
characteristics and climate.
Traction ± AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B,
and C. Those grades represent the tire's ability to stop on
wet pavement as measured under controlled conditions
on speci®ed government test surfaces of asphalt and
concrete. A tire marked C may have poor traction
performance. Warning: The traction grade assigned to
this tire is based on straight-ahead braking traction tests,
and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
5-75

Tire Chains
{CAUTION:
If your vehicle has dual wheels or P265/75R16,
LT265/75R16 or P275/55R20 size tires, don't
use tire chains. They can damage your vehicle
because 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.²
Notice:If your vehicle does not have dual wheels
and is equipped with a tire size other than
P265/75R16, LT65/75R16 or P275/55R20, use tire
chains only where legal and only when you must.
Use chains that are the proper size for your
tires. Install them on the tires of the rear axle. Don't
use chains on the tires of the front axle. Tighten
them as tightly as possible with the ends securely
fastened. Drive slowly and follow the chain
manufacturer's instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until
it stops. Driving too fast or spinning the wheels with
chains on will damage your vehicle.
5-78

Capacities and Speci®cations
Please refer toPart D: Recommended Fluids and Lubricants on page 6-19for more information. All capacities are
approximate. When adding see the refrigerant charge label under the hood for charge capacity information and
requirements.
Capacities and Speci®cations
Engine Type VIN Code Spark Plug Gap
VORTECŸ 4300 V6 V6 W 0.060 inches (1.52 mm)
VORTECŸ 4800 V8 V8 V 0.060 inches (1.52 mm)
VORTECŸ 5300 V8 V8 T 0.060 inches (1.52 mm)
VORTECŸ 6000 V8 V8 U 0.060 inches (1.52 mm)
VORTECŸ 6000 V8 V8 N 0.060 inches (1.52 mm)
VORTECŸ 8100 V8 V8 G 0.060 inches (1.52 mm)
Model Description Torque
C/K 1500 & C/K 2500 6 Bolts (14 mm) 140 lb ft (190Y)
C/K 3500 8 bolts (14 mm) 140 lb ft (190Y)
Tire PressureSee the Certi®cation/Tire label on the rear edge of the driver's
door or the incomplete vehicle document in the cab.
5-118