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When It's 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.
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, see ªWheel
Nut Torqueº 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.
If you're going to be doing a lot of driving on
high
-crown roads, you can reduce tire wear by adding
5 psi (35 kPa) to the tire pressure in the outer tires. Be
sure to return to the recommended pressures when no
longer driving under those conditions. See ªTiresº and
ªInflation
- Tire Pressureª in the Index for more
information on proper tire inflation.
CAUTION:
If you operate your vehicle with a tire that is
badly underinflated, the tire can overheat. An
overheated tire can lose air suddenly or catch
fire. You or others could be injured. Be sure all
tires (including the spare) are properly inflated.
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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.
Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, 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, see ªWheel Nut Torqueº
in the Index.
See ªChanging a Flat Tireº in the Index for
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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Capacities and Specifications
Please refer to ªRecommended Fluids and Lubricantsº in the Index for more information. All capacities are
approximate. When adding see the refrigerant charge label under the hood for charge capacity information and
requirements.
Engine Type VIN Code Spark Plug Gap
VORTEC 4300 V6 W 0.060 inches (1.52 mm)
VORTEC 4800 V8 V 0.060 inches (1.52 mm)
VORTEC 5300 V8 T 0.060 inches (1.52 mm)
VORTEC 6000 V8 U 0.060 inches (1.52 mm)
VORTEC 6600 V8 1 0.060 inches (1.52 mm)
VORTEC 8100 V8 G 0.060 inches (1.52 mm)
Wheels and Tires
Model Description Torque
C/K 1500 & C/K 2500 6 bolts (14 mm)
140 lb
-ft (190 N´m)
C/K 3500 8 bolts (14 mm)
140 lb
-ft (190 N´m)
Tire Pressure See the Certification/Tire label on the rear edge of the driver's door
or the incomplete vehicle document in the cab.