Page 353 of 398

❑Replace fuel filter(s) (or every 12 months, whichever
occurs first).(2)
❑Steering system service.(12)
❑Front and rear suspension service.(13)
❑Spring-to-axle U-bolts and shackle bolts service.(15)
❑Exhaust system service (or every 6 months,
whichever occurs first).(2) (3) (16)
❑Inspect door hinge pins and bushings and replace as
necessary.
❑Wheel bearing (grease type) service (and whenever
hubs are removed).(22) (36)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(6) (36)
❑Parking brake service (or every 6 months, whichever
occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).❑Clean air brake application valve (or every 3 months,
or every 300 hours, whichever occurs first). Lubricate
linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)
❑Air brake system valve service (or every 3 months,
or every 900 hours, whichever occurs first).(37)
❑C600, C700, and C800 Gasoline Engines
Only: Engine drive belts service (or every 12 months,
whichever occurs first).(17)
❑Thermostatically controlled engine cooling fan
service.(3) (19)
❑Shields and underhood insulation service.(3) (4) (20)
❑Rear axle air shift motor service.(10)
❑Air intake system service (or every 24 months,
whichever occurs first).(3) (4) (23)
❑Evaporative Control System service, if equipped, (or
every 24 months, whichever occurs first).(2) (24) †
❑Air compressor dry element pleated paper air strainer
service (or every 2 months or every 800 hours,
whichever occurs first).
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96,000 Miles (152 000 km)
❑7.8L DURAMAX®Diesel Without Engine Oil Life
System Only: Change engine oil and filter
(or every 12 months, or every 600 hours of engine
operation, whichever occurs first).(2)
❑7.8L DURAMAX
®Diesel With Engine Oil Life System
Only: Check oil life system (or every 12 months, or
every 600 hours of engine operation, whichever
occurs first). If engine oil and filter are changed, reset
system. See “Engine Oil (DURAMAX
®Diesel)” in
the Index.(2) (7)
❑Lubricate U-joints (or every 6 months, whichever
occurs first).
97,500 Miles (156 000 km)
❑Gasoline Engine Only: Check engine oil life system.
If engine oil and filter are changed, reset system.
See “Engine Oil (Gasoline Engine)” in the
Index.(2) (8)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (5)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(6) (36)❑Parking brake service (or every 6 months, whichever
occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).
❑Clean air brake application valve (or every 3 months,
or every 300 hours, whichever occurs first). Lubricate
linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)100,000 Miles (160 000 km)
❑Diesel Only: Inspect engine drive belt; replace as
necessary.
❑Gasoline Engine Only (Vehicles with GVW of
16,000 lbs or less): Spark plug service.(2) (25)
❑Change power steering fluid (or every 36 months,
whichever occurs first).(12)
❑Replace power steering reservoir filter element (or
every 24 months, whichever occurs first).
❑Wheel bearing (oil type) service (and whenever hubs
are removed).(22) (36)
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(14)= Adjust tire pressures as indicated on the Gross
Vehicle Weight (GVW) Rating label for optimum tire life.
SeeTires on page 5-74for further details. Check
tires for excessive or abnormal wear or damage. Also
check for damaged wheels. Replace wheels and/or tires
as needed.
(15)= 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.
(16)= 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.
(17)= Check all gasoline engine drive belts for cracks,
fraying, and wear. Replace as needed.
(18)= Adjust valve lash. Incorrect valve clearance will
result in increased engine noise and reduced engine
output.(19)= 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.
(20)= Check shields and underhood insulation for
damage or looseness. Adjust or replace as needed.
(21)= Inspect parking brake drum and linings for wear
or cracks and check linkage and adjustment.
(22)= Wheel bearing service:
•Grease type — Clean, inspect, and lubricate with
the proper wheel bearing grease at designated
intervals or when hubs are removed. See
Part C: Recommended Fluids and Lubricants on
page 6-33.
•Oil-filled type — Some wheel bearings are
lubricated by axle lubricant. When you have oil-filled
hubs, use lubricant identical to that used in the
axle. Lubricant change intervals are the same for
front and rear axles. However, you must maintain
the proper oil level between change intervals.
SeeFront Wheel Bearings with Oil-Filled Hubs on
page 5-73andPart C: Recommended Fluids
and Lubricants on page 6-33.
6-25