GMC 2003 C4C042, Owner'S Manual

Page: 353 / 386

7-7
j Wheel bearing (grease type) service (or every
24 months, whichever occurs first, and whenever
hubs are removed). (23)(46)
j Wheels and tires service. (15)
j Parking brake service (or every 6 months, whichever
occurs first). (8)
j Air intake system service (or every 24 months,
whichever occurs first). (4)(5)(24)
j Evaporative Control System service (if equipped) (or
every 24 months, whichever occurs first). (3)(26)
[
j Rear axle air shift motor service. (11)
j Air brake service (or every 6 months, whichever
occurs first). (39)
j Air brake automatic slack adjuster service
(or every 500 hours, whichever occurs first). (40)
j Check air brake relay valve operation and check
for leaks (or every month, or every 300 hours,
whichever occurs first).
j Clean air brake application valve (or every 3 months,
or every 300 hours, whichever occurs first); lubricate
linkage.
j Air brake chamber service (or every 2 months,
whichever occurs first). (41)
j Trailer brake hand control valve service (or every
3 months, or every 900 hours, whichever
occurs first). (42)
j L18/LB7 Engines Only: Clutch pedal free
travel service. (10)
30,000 Miles (48 000 km)
j Gasoline Engine Only: Check Oil Life System.
If engine oil and filter are changed, reset system.
See “Engine Oil” in the Index. (3)(9)
j DURAMAXt Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first). (2)(3)
j Check fluid levels (or every 3 months, whichever
occurs first). (1)(6)
j DURAMAXt Diesel Only: Replace fuel filter.
j Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
j Replace fuel filter(s) (or every 12 months, whichever
occurs first). (3)
j Steering system service. (13)
j Front and rear suspension service. (14)
j Spring
-
to
-
axle U
-
bolts and shackle bolts
service. (16)
j Exhaust system service (or every 6 months,
whichever occurs first). (3)(4)(17)
(Continued)