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Wheel Loading
Wheels are stamped with a maximum load and
cold inflation rating. Be sure you do not exceed
these limits. If you ever think you need to exceed
these limits, first contact the rim and wheel
maker to get their advice.
Dual Tire Operation
When the vehicle is new, check the wheel nut
tightness on all wheels with a torque wrench after
your first 100 miles (160 km) and then 1,000 miles
(1 600 km) after that. Whenever a wheel, wheel
bolt or wheel nut is removed or serviced,
repeat the 100 miles (160 km), and then 1,000 mile
(1 600 km) wheel nut tightness check.SeeTightening the Wheel Nuts on page 325for
wheel nut tightening information and proper
torque values.
{CAUTION:
If you operate your vehicle with a tire that
is badly underin ated, the tire can
overheat. An overheated tire can lose air
suddenly or catch re. You or others could
be injured. Be sure all tires (including the
spare, if any) are properly in ated.
SeeTires on page 321andIn ation - Tire
Pressure on page 322for more information on
proper tire inflation.
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How Often to Check
Wheel tightness is so important you should have a
technician check nut tightness on all wheels with a
torque wrench after your first 100 miles (160 km),
and then 1,000 miles (1 600 km) after that. Be sure
to repeat this service whenever you have a tire
removed or serviced. SeeScheduled Maintenance
on page 363for further information.
Wheel Replacement
Replace any wheel that is bent, cracked or badly
rusted or corroded. If wheel nuts keep coming
loose, replace the wheel. If the wheel leaks
air, replace it.
Your dealer will know the kind of wheel you need.
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:
A leaking wheel could fail without warning.
A wheel designed for tubeless tires could
be leaking because it is damaged. Do not
use an inner tube or some other thing to try
to stop the leaking. Get a new wheel of the
proper type.
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(13)= Check front and rear suspension. Look
for damaged, loose, or missing parts or parts
showing signs of wear or lack of lubrication.
Replace parts as needed.
(14)= Adjust tire pressures as indicated on the
Certification or Tire Information label for optimum
tire life. SeeTires on page 321for further
details. Check tires for excessive or abnormal
wear or damage. Also check for damaged wheels.
Replace wheels and/or tires as needed.
(15)= Check spring-to-axle U-bolts and shackle
bolts for proper torque. See the service manual for
torque sequence and specifications. When parts
are replaced, the torque must be checked and
adjusted more often during the first 6,000 miles
(10 000 km). Check torque at 500 miles (800 km)
and 2,000 miles (3 000 km) after first use of parts.
(16)= Check complete exhaust system and
cab areas near the exhaust system for broken,
damaged, missing, or out-of-position parts.
Also inspect for open seams, holes, loose
connections, or other conditions which could let
exhaust fumes seep into the driver compartment.Needed repairs should be made at once. To help
maintain system integrity, replace exhaust
pipes whenever a new muffler is put on.
(17)= Check all gasoline engine drive belts for
cracks, fraying, and wear. Replace as needed.
(18)= Adjust valve lash. Incorrect valve clearance
will result in increased engine noise and reduced
engine output.
(19)= With the engine off and below normal
operating temperature, check to see that
the thermostatically controlled engine cooling fan
can be rotated by hand on viscous-operated
drives. Replace as needed.
(20)= Check shields and underhood insulation
for damage or looseness. Adjust or replace
as needed.
(21)= Inspect parking brake drum and linings for
wear or cracks and check linkage and adjustment.
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