2003 CHEVROLET C/K brake

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.

7-20
(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.

7-23
Body Lubrication Service
Lubricate all exposed surfaces such as door checks, door
lock bolts, lock strike plates, door latches and dovetail
bumper wedges. Where oil holes are provided a dripless
oil can be used. The seat adjusters, seat track, door
weatherstrips and rubber cap bumpers should also be
lubricated.
Part C tells you what to use. More frequent lubrication
may be required when exposed to a corrosive
environment.
Parking Brake Check
Park on a fairly steep hill and hold the vehicle with the
parking brake only. This checks holding ability.Starter Switch Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the
regular brakes. See ªParking Brakeº in the Index
if necessary.
Do not use the accelerator pedal, and be ready to turn
off the engine immediately if it starts.
3. On automatic transmission vehicles, try to start the
engine in each gear. The starter should work only in
PARK (P), if equipped, or NEUTRAL (N). If the
starter works in any other position, your vehicle
needs service.

7-24
Automatic Transmission Shift Indicator Check
Check that the indicator points to the gear chosen.
Steering Check
Be alert for any changes in steering action, abnormal
front tire wear or steering wheel position. An inspection
or service is needed when the steering wheel is harder to
turn or has too much free play, or if there are strange
sounds when turning or parking.
Brake System Check
Be alert to illumination of the low air warning lamp or
for the tone alarm, or changes in braking action, such
as repeated pulling to one side, unusual sounds when
braking or increased brake pedal travel. Make sure air
brake system reservoirs are drained daily with full
system air pressure, and check system for leaks. Any
of these conditions could indicate the need for brake
system inspection and/or service.Engine Cooling System Service
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed. Clean the outside
of the radiator and air conditioning condenser. To help
ensure proper operation, a pressure test of the cooling
system and pressure cap is recommended at least once
a year.
Exhaust System Check
Be alert for any changes in the sound of the exhaust
system or any smell of fumes. These are signs the
system may be leaking. Have it checked and/or repaired
at once. Refer to ªEngine Exhaustº and ªRunning Your
Engine While You're Parkedº in the Index.
Windshield Wipers and Washers Check
Check operation and condition of the wiper blades.
Check the flow of the washer spray.

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.

7-26
Fluid Leaks Check
Check for fuel, coolant, oil or other fluid leaks by
looking at the surface beneath the vehicle after it has
been parked for awhile.
Underbody Inspection
Corrosive materials used for ice, snow removal and dust
control can collect on the underbody. If these materials
are not removed, accelerated corrosion (rust) can occur
on underbody parts such as fuel lines, frame, floor pan
and exhaust system. At least every spring, flush these
materials from the underbody with plain water. Take
care to clean well any areas where mud and other debris
can collect. Sediment packed in closed areas of the
frame should be loosened before being flushed.
Engine Cover Check
Check that the cab's engine cover and seal (if equipped)
are not torn or damaged. Be sure that the cover is
clamped down firmly to the floor.At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part C.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
Tractor Protection (Breakaway) Valve Check
On air brake models, remove, disassemble, clean and
inspect the tractor protection (breakaway) valve.

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).