2003 CHEVROLET C/K belt

7-15

Exhaust brake service (if equipped). Check for
excessive spindle free play and smooth operation.
Lubricate ball joint cap.

Air compressor dry element pleated paper air strainer
service (or every 2 months or every 800 hours,
whichever occurs first).

Inspect air compressor discharge port (or every
6 months or every 1,800 hours, whichever
occurs first).

Manual transmission (ZF 6
-speed only) fluid
replacement (or every 48 months, whichever
occurs first).
120,000 Miles (192 000 km)

C600, C700 and C800 Gasoline Engines Only:
Replace engine drive belts.
150,000 Miles (240 000 km)

Cooling system service (or every 60 months since
last service, whichever occurs first). (3)(35)

Diesel Engine Only: Inspect engine drive belt;
replace as necessary.
200,000 Miles (320 000 km)

Remove, disassemble, clean and inspect the air
brake trailer supply valve (or every 2 years, or
every 7,200 hours, whichever occurs first).

Diesel Engine Only: Inspect engine drive belt;
replace as necessary.

C400 and C500 Gasoline Engines Only: Inspect
drive belts; replace as necessary. (18)
250,000 Miles (400 000 km)

Wheel bearings service -- Eaton Axle (oil-filled) (or
every 36 months, whichever occurs first). (23)(46)

Rear axle service
-- Eaton, Rockwell, Spicer Axles
(or every 36 months, whichever occurs first). (37)

Manual transmission (except ZF 6
-speed) fluid
replacement (or every 60 months, whichever
occurs first).
300,000 Miles (480 000 km)

Remove, disassemble, clean and inspect the air brake
air dryer (or every 3 years, or 10,800 hours,
whichever occurs first). Replace dessicant on
Bendix
-Westinghouse units.

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.

7-22 At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light (if equipped)
and all your belts, buckles, latch plates, retractors and
anchorages are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from
doing its job, have it repaired. Have any torn or frayed
safety belts replaced.
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace blade
inserts that appear worn or damaged or that streak or
miss areas of the windshield. Also see ªWiper Blades,
Cleaningº in the Index.Engine Air Cleaner Filter Restriction
Indicator Check
Your vehicle has an indicator located on the air cleaner
in the engine compartment that lets you know when the
air cleaner filter is dirty and needs to be changed. Check
indicator at least twice a year or when your engine oil is
changed, whichever occurs first. See ªEngine Air
Cleanerº in the Index for more information. Inspect your
air cleaner filter restriction indicator more often if the
vehicle is used in dusty areas.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. See ªRecommended Fluids and Lubricantsº in
the Index.