2003 CHEVROLET C/K wheel torque

5-27
Changing a Flat Tire
Your truck, when new, did not include tire changing
equipment or a place to store a tire in the vehicle.
Few drivers of these vehicles have the necessary
equipment aboard to be able to change a flat tire safely.
For example, you would need 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.
CAUTION:
If you try to put air back into a tire that has run
flat, or even a tire that was quite low on air, 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.
So if you're stopped somewhere by a flat or damaged
tire or wheel, you should get expert help. See ªRoadside
Assistanceº in the Index.
CAUTION:
Your vehicle, when new, did not include tire
changing equipment or a place to store a tire in
the vehicle. Special tools and procedures are
required if a tire needs to be serviced. If these
tools and procedures aren't used, you or others
could be injured or killed while trying to change
or service a truck tire.

6-60
When to Check
Check your tires once a month or more. Also, check the
tire pressure of the spare tire (if equipped).
How to Check
Use a good quality pocket
-type gage to check tire
pressure. You can't tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they're underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Rims and Wheels
Rims and wheels are stamped with a maximum load
and cold inflation rating. Be sure you don't exceed
these limits.
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.
See ªTightening the Wheel Nutsº later in this section
for proper torque values and wheel nut tightening
information.
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, if any) are properly
inflated.
See ªTiresº and ªInflation -- Tire Pressureº in the Index
for more information on proper tire inflation.

6-65
CAUTION:
Rust or dirt on a 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 a crash. 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 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.
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. See ªMaintenance Scheduleº in the Index for
further information.

7-18
(15) = Adjust tire pressures as indicated on the GVW
Rating label for optimum tire life. See ªTiresº in the
Index for further details. Check tires for excessive or
abnormal wear or damage. Also check for damaged
wheels. Replace wheels and/or tires as needed.
(16) = 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.
(17) = 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.
(18) = Check all gasoline engine drive belts for cracks,
fraying and wear. Replace as needed.(20) = 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.
(21) = Check shields and underhood insulation for
damage or looseness. Adjust or replace as needed.
(23) = Wheel bearing service:

Grease type
-- Clean, inspect and lubricate with the
proper wheel bearing grease at designated intervals
or when hubs are removed. See ªRecommended
Fluids and Lubricantsº in the Index.

Oil
-filled type -- Some wheel bearings are lubricated
by rear axle lubricant. When you have oil
-filled
hubs, use lubricant identical to that used in your rear
axle. Lubricant change intervals are the same for
front and rear axles. However, you must maintain oil
level at the OIL LEVEL mark between change
intervals. See ªRecommended Fluids and
Lubricantsº in the Index.
(24) = Check the air intake system installation to see that
gaskets are seated properly and all hose connections,
fasteners and other components are tight. Tighten
connections and fasteners or replace parts as required.

7-20
(39) = Air brake service:

Inspect brake lines and hoses for proper hook
-up,
binding, leaks, cracks, chafing, etc. Inspect drum
brake linings for wear or cracks. Inspect other brake
parts at each wheel, including drums, wheel
cylinders and piston heat shields, boots and wheel
speed sensor wiring. Check brake pedal for excessive
free play or travel (or every 6 months, whichever
occurs first) and have serviced if needed. Check
brakes more often if driving habits and conditions
result in frequent braking. Replace air dryer cartridge
only if excessive oil or moisture is present. A small
amount of oil in the system is normal and should not
be considered as a reason to replace the cartridge.

Test air lines for leaks; tighten as needed. Replace
compressor filter.

Inspect air parking brake chamber for leaks and
damage. Inspect lines and hoses for leaks, cracks,
chafing, etc. Also check all attachments for
tightness, wear or damage. Note: The spring brake
section of the rear brake diaphragms are
non
-serviceable.

Replace the air compressor filter element, mounted
on the air compressor. For remote air compressor
intake service, refer to engine air cleaner filter
replacement.
Remove, disassemble, clean and inspect the safety
valve, standard brake chamber, quick release valve,
quick release/double check valve combination,
parking brake control valve, double check valve,
pressure protection valve and alcohol injector.

Remove, disassemble and clean the application
valve; replace parts showing wear.

Remove, disassemble, clean and inspect the spring
brake control valve; replace rubber parts.
(40) = Clean and lubricate air brake automatic slack
adjuster. Check pushrod travel and auto adjustment
operation. Have serviced if needed.
(41) = Air brake chamber service: Check operation,
mounting, clamps and air lines and check for leaks.
(42) = Trailer brake hand control valve service: Check
operation; lubricate cam and follower.
(46) = Tighten the wheel stud nuts to the specified
torque values at 100 miles (160 km). Thereafter, tighten
them 1,000 miles (1 600 km) after each time the wheel
is removed. See ªTightening the Wheel Nutsº in
the Index.