2003 CHEVROLET C/K manual

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.

7-16
Footnotes

= The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to the
completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the maintenance
be recorded.
(1) = If your vehicle has an Allison automatic
transmission, your GM owner's manual is supplemented
by an Allison Transmission Operator's Manual. Always
refer to these manuals for related maintenance services.
(2) = Refer to the Caterpillar Diesel Engine Operation
and Maintenance Manual for oil recommendations and
change intervals.
(3) = An Emission Control Service.
(4) = A Noise Emission Control Device.
(5) = Applies only to vehicles sold in the United States.(6) = Check fluid level in brake master cylinder, power
steering pump, axle, transmission and hydraulic spring
parking brake pump (if equipped). A low fluid level in
the brake master cylinder can indicate worn brake
linings and should be checked accordingly.
(7) = Inspect brake lines and hoses for proper hook
-up,
binding, leaks, cracks, chafing, etc. Inspect disc brake
pads for wear and rotors for surface condition. Inspect
caliper assemblies. 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.
(8) = Inspect parking brake drum and linings for wear or
cracks and check linkage and adjustment.
(9) = This vehicle has the GM Oil Life System. This
system will show you when to change the engine oil and
filter
-- usually between 3,000 miles (5 000 km) and
7,500 miles (12 000 km) since your last oil change.
Under severe conditions, the indicator may come on
before 3,000 miles (5 000 km). Never drive your vehicle
more than 7,500 miles (12 000 km) or 12 months
without an oil and filter change.
Remember to reset the Oil Life System whenever the oil
is changed. For more information, see ªChange Oil
Lightº in the Index.

7-17
(10) = Check clutch pedal for free travel. Press pedal
by hand until resistance is felt. Free travel should be
maintained at 1.5 to 2 inches (38 to 51 mm) measured
at the clutch pedal pad. Make checks at 1,000 miles
(1 600 km) and then at every 7,500 mile (12 000 km)
interval thereafter.
(11) = Inspect rear axle air shift motor for fluid leaks.
Remove plug to check fluid level. Inspect air lines and
hoses for proper hook
-up, binding, leaks, etc. Inspect at
3,000 miles (5 000 km) and 22,500 miles (36 000 km)
and then every 22,500 miles (36 000 km) thereafter.
(12) = Chassis Lubrication Service: Lubricate all grease
fittings in front suspension, front axle and steering
linkage. DO NOT lubricate kingpin bushings with air
pressure equipment; instead, use a hand grease gun to
ensure complete purge and eliminate sealer cap
distortion. Lubricate transmission and shift linkage,
hood latches and hood hinges, parking brake lever pivot,
clevis pins and linkage, disc brake caliper rails, clutch
linkage and release bearing (if equipped), bearing pads,
propshaft universal joints, brake camshaft bracket, slack
adjusters, pedal shaft, clutch cross shaft and clutch pedal
springs. Lubricate suspension, axle and steering linkage
more often when operating under dusty or muddy
conditions and in excessive off
-road use.(13) = Check steering system:

Look for damaged, loose or missing parts. Also look
for parts showing signs of wear or lack of lubrication.
Replace parts as needed. Also check steering gear
mounting bolts, pitman arm nut, gear housing upper
cover and side cover attaching bolts, steering column
mounting bolts and cardan joint clamp bolts; tighten
if necessary. (See service manual.)

Inspect power steering hoses, tubes and fittings for
leaks. Hoses and lines must not be twisted, kinked or
tightly bent. Make sure clips, clamps, supporting
tubes and hoses are in place and properly secured.

Check steering gear for leakage around pitman shaft
and housing. If leakage is evident (lubricant oozing
out, not just oily film), leak should be corrected
immediately.
(14) = 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.

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.

7-19
(26) = Evaporative Control System Service
(if equipped): Check all fuel and vapor lines and hoses
for proper connections and correct routing (or every
24 months, whichever occurs first). Replace parts
as needed.
(28) = Replace spark plugs. Inspect wires for damage.
Check the wire boot and boot heat shield fit at spark
plugs and coil. Replace parts as needed.
(30) = Check the fuel tank, fuel cap and fuel lines for
damage which could cause leakage. Inspect fuel cap for
correct sealing ability and any indications of damage.
Check fuel cap gasket for even filler neck imprint.
Replace parts as needed.
(31) = Check EGR system as described in the
service manual. See ªService and Owner Publicationsº
in the Index.(32) = Inspect Electronic Vacuum Regulator Valve
(EVRV) filter for excessive contamination or plugging.
If needed, clean filter with solution of soap and water,
let dry and install.
(35) = Drain, flush and refill cooling system. See
ªRecommended Fluids and Lubricantsº in the Index for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap and neck. Pressure test cooling system and
pressure cap. For Caterpillar

diesel engines, always
refer to the Caterpillar Diesel Engine Operation &
Maintenance Manual for coolant recommendations and
change intervals.
(37) = Rear axle service: Change the lubricant. See
ªRecommended Fluids and Lubricantsº in the Index.
(38) = Front axle service: Re
-pack upper kingpin
roller bearing.

7-25
Defroster Check
Move the control to the defrost symbol and the fan to
HI or the high symbol. Then check the airflow from the
ducts at the inside base of the windshield.
Mirrors and Sun Visors Check
Check that friction joints hold mirrors and sun visors
in place.
Seat Adjuster Check
When adjusting a manual seat, be sure seat adjusters
latch by attempting to move the seat after latching.
Lamps Check
Check panel lighting, warning lights, indicator lights
and interior lamps. On the outside, check: license plate
lamps, sidemarker lamps, reflectors or lights on outside
mirrors, headlamps, parking lamps, identification and
clearance lamps, taillamps, brake lamps, turn signals,
backup lamps and hazard warning flashers. Have
headlamp aim checked at once if beams seem
improperly aimed.Glass, Mirrors, Lamps and/or Reflectors
Condition Check
Look for broken, scratched, dirty or damaged glass,
mirrors, lamps or reflectors that could reduce the view
or visibility or cause injury. Replace, clean or repair
promptly.
Door Latches Check
Check that doors close, latch and lock tightly. Check for
broken, damaged or missing parts that might prevent
tight latching.
Hood Latches Check
Check that the hood closes firmly. Check for broken,
damaged, loose or missing parts that might prevent tight
latching. Make sure the secondary latch (if equipped)
keeps the hood from opening all the way when the
primary latch is released.

7-27
Part C: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name,
part number or specification may be obtained from
your dealer.
USAGE
FLUID/LUBRICANT
Engine Oil
(Gasoline
Engine)Engine oil with the American
Petroleum Institute Certified for
Gasoline Engines starburst symbol
of the proper viscosity. To
determine the preferred viscosity
for your vehicle's engine, see
ªEngine Oilº in the Index.
Engine Oil
(Caterpillar
Diesel Engine)See the Caterpillar
Operation &
Maintenance Manual for engine
oil recommendations.
USAGEFLUID/LUBRICANT
Engine Coolant
(Gasoline
Engine &
DURAMAX
Diesel)50/50 mixture of clean, drinkable
water and use only DEX
-COOL

Coolant. See ªEngine Coolantº in
the Index.
Engine Coolant
(Caterpillar
Diesel Engine)See the Caterpillar
Operation &
Maintenance Manual for engine
coolant recommendations.
Hydraulic Brake
SystemDelco Supreme 11
Brake Fluid
or equivalent DOT
-3 brake fluid.
Windshield
Washer SolventGM Optikleen
Washer Solvent
or equivalent.
Clutch Bearing
LubricantClutch Bearing Lubricant
(GM Part No. 12378484 or
equivalent NLGI #3 consistency).

7-28
USAGEFLUID/LUBRICANT
Exhaust Brake
Ball Joint Cap
LubricantHigh-Temperature Grease
(GM Part No. U.S. 1051344, in
Canada 903037, or equivalent) or
NLGI #3 consistency.
Power Steering
SystemDEXRON
-III Automatic
Transmission Fluid.
Manual
Transmission
(Except ZF
6
-Speed)
Synthetic Manual
Transmission Fluid
(GM Part No. U.S. 12345724,
in Canada 10953510).
Manual
Transmission
(ZF 6
-Speed)
TranSynd Synthetic
Transmission Fluid
(GM Part No. U.S. 12378515,
in Canada 88900701).
USAGEFLUID/LUBRICANT
Automatic
TransmissionSee the Allison Transmission
Operator's Manual for correct
transmission fluid.
Chassis
LubricationChassis Lubricant
(GM Part No. U.S. 12377985, in
Canada 88901242, or equivalent)
or lubricant meeting requirements
of NLGI # 2, Category LB
or GC
-LB.
Front Wheel
Bearing Grease
(Except Oil
Filled Hubs)Wheel bearing lubricant meeting
requirements of NLGI # 2,
Category GC or GC
-LB
(GM Part No. U.S. 1051344, in
Canada 993037, or equivalent).