70,000 Miles (112 000 km)
❑DURAMAX™ Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first).(2) (3)
75,000 Miles (120 000 km)
❑Gasoline Engine Only: Check Oil Life System. If
engine oil and filter are changed, reset system. See
“Engine Oil (Gasoline Engine)” in the Index.(3) (9)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(12)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (6)
❑Gasoline Engine: Inspect engine air cleaner filter if you
are driving in dusty conditions and replace filter if
necessary. Diesel Engine: Inspect engine air cleaner
filter change indicator. If necessary, replace the filter. If
vehicle is driven in dusty/dirty conditions, inspect filter
change indicator at every engine oil change. See
Engine Air Cleaner/Filter on page 5-30for more
information.† (3)
❑DURAMAX™ Diesel Only: Replace fuel filter.
❑Steering system service.(13)
❑Front and rear suspension service.(14)
❑Spring-to-axle U-bolts and shackle bolts service.(16)
❑Exhaust system service (or every 6 months, whichever
occurs first).(3) (4) (17)❑Wheels and tires service.(15)
❑Hydraulic brake service (or every 6 months, whichever
occurs first).(7) (46)
❑Parking brake service (or every 6 months, whichever
occurs first).(8)
❑Air brake service (or every 6 months, whichever
occurs first).(39)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(40)
❑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).(41)
❑Trailer brake hand control valve service (or every
3 months, or every 900 hours, whichever occurs
first).(42)
❑Fuel tank, fuel cap and fuel lines service (or every
72 months, whichever occurs first).(3) (30) †
❑EGR system inspection (if equipped) (or every
72 months, whichever occurs first).(3) (31)
❑Thermostatically controlled engine cooling fan
service.(4) (20)
❑Shields and underhood insulation service.(4) (5) (21)
6-14
80,000 Miles (128 000 km)
❑DURAMAX™ Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first).(2) (3)
❑Air compressor dry element pleated paper air strainer
service (or every 2 months or every 800 hours,
whichever occurs first).
82,500 Miles (132 000 km)
❑Gasoline Engine Only: Check Oil Life System. If
engine oil and filter are changed, reset system.
See “Engine Oil (Gasoline Engine)” in the
Index.(3) (9)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (6)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(12)
❑Wheels and tires service.(15)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(7) (46)
❑Parking brake service (or every 6 months, whichever
occurs first).(8)
❑Air brake service (or every 6 months, whichever
occurs first).(39)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(40)❑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).(41)
❑Trailer brake hand control valve service (or every
3 months, or every 900 hours, whichever occurs
first).(42)
❑Wheel bearings service – Eaton Axle (oil-filled) (or
every 24 months, whichever occurs first).(23) (46)
90,000 Miles (144 000 km)
❑Gasoline Engine Only: Check Oil Life System. If
engine oil and filter are changed, reset system.
See “Engine Oil (Gasoline Engine)” in the
Index.(3) (9)
❑DURAMAX™ Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first).(2) (3)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (6)
6-15
❑Gasoline Engine: Replace engine air cleaner filter.
Diesel Engine: Inspect engine air cleaner filter
change indicator. If necessary, replace the filter. If
vehicle is driven in dusty/dirty conditions, inspect filter
change indicator at every engine oil change. See
Engine Air Cleaner/Filter on page 5-30for more
information.† (3)
❑DURAMAX™ Diesel Only: Replace fuel filter.
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(12)
❑Cooling system service. Clean the cooling system
filler cap with clean water, clean the core, pressure
test the cap and the system for proper pressure
capability and inspect condition of cooling and heater
hoses and clamps. Replace hoses if cracked,
swollen or damaged.
❑Wheel bearing (grease type) service (or every
24 months, whichever occurs first, and whenever
hubs are removed).(23) (46)
❑Replace fuel filter(s) (or every 12 months, whichever
occurs first).(3)
❑Steering system service.(13)
❑Front and rear suspension service.(14)
❑Spring-to-axle U-bolts and shackle bolts service.(16)
❑Exhaust system service (or every 6 months,
whichever occurs first).(3) (4) (17)❑Inspect door hinge pins and bushings and replace as
necessary.
❑Wheels and tires service.(15)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(7) (46)
❑Parking brake service (or every 6 months, whichever
occurs first).(8)
❑Air brake service (or every 6 months, whichever
occurs first).(39)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(40)
❑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).(41)
❑Trailer brake hand control valve service (or every
3 months, or every 900 hours, whichever occurs
first).(42)
❑C600, C700 and C800 Gasoline Engines Only:
Engine drive belts service (or every 12 months,
whichever occurs first).(18)
6-16
❑Thermostatically controlled engine cooling fan
service.(4) (20)
❑Shields and underhood insulation service.(4) (5) (21)
❑Rear axle air shift motor service.(11)
❑Air intake system service (or every 24 months,
whichever occurs first).(4) (5) (24)
❑Evaporative Control System service (if equipped) (or
every 24 months, whichever occurs first).(3) (26) †
97,500 Miles (156 000 km)
❑Gasoline Engine Only: Check Oil Life System. If
engine oil and filter are changed, reset system.
See “Engine Oil (Gasoline Engine)” in the
Index.(3) (9)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (6)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(12)
❑Wheels and tires service.(15)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(7) (46)
❑Parking brake service (or every 6 months, whichever
occurs first).(8)
❑Air brake service (or every 6 months, whichever
occurs first).(39)❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(40)
❑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).(41)
❑Trailer brake hand control valve service (or every 3
months, or every 900 hours, whichever occurs
first).(42)
100,000 Miles (160 000 km)
❑DURAMAX™ Diesel Only: Change engine oil
and filter (or every 12 months, whichever occurs
first).(2) (3)
❑Diesel Only: Inspect engine drive belt; replace as
necessary.
❑Gasoline Engine Only (Vehicles with GVW of
16,000 lbs. or less): Spark plug service.(3) (28)
❑Change power steering fluid (or every 36 months,
whichever occurs first).(13)
6-17
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 desiccant on
Bendix-Westinghouse units.
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, seeChange Engine
Oil Light on page 3-39.
6-19
(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.
(15)= Adjust tire pressures as indicated on the GVW
Rating label for optimum tire life. SeeTires on page 5-68
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. SeePart C:
Recommended Fluids and Lubricants on page 6-29.
•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. SeePart C: Recommended Fluids and
Lubricants on page 6-29.
6-21
(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.
(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. SeeService Publications Ordering Information
on page 7-7.(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. SeePart C:
Recommended Fluids and Lubricants on page 6-29
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
Part C: Recommended Fluids and Lubricants on
page 6-29.
(38)= Front axle service: Re-pack upper kingpin roller
bearing.
6-22
Driving on Snow or Ice....................................4-26
Driving Through Deep Standing Water...............4-20
Driving Through Flowing Water.........................4-20
Dual Tire Operation.........................................5-69
E
Eaton®Fuller®Five and Six-Speed
Transmissions and TTC Spicer Seven-Speed
Transmissions.............................................2-30
Eaton
®Fuller®Nine and Ten-Speed
Non-Synchronized Manual Transmissions........2-32
Electric Air Compressor...................................5-51
Electrical Connections......................................4-36
Electrical System
Add-On Equipment......................................5-86
Fuses and Circuit Breakers...........................5-87
Fusible Links..............................................5-87
Headlamp Wiring.........................................5-86
Power Windows and Other Power Options......5-87
Windshield Wiper Fuses...............................5-87
Elevated Idle/Exhaust Restrictor........................2-21
Engine
Air Cleaner/Filter.........................................5-30
Battery.......................................................5-55
Change Engine Oil Light...............................3-39
Check and Service Engine Soon Light............3-37Engine (cont.)
Checks Before Operating..............................2-22
Coolant..............................................5-32, 5-35
Coolant Heater............................................2-23
Coolant Temperature Gage...........................3-35
Diesel Engine Exhaust Brake........................2-25
Drive Belt Routing......................................5-103
Exhaust.....................................................2-37
Fan Noise..................................................5-43
Oil .....................................................5-20, 5-25
Overheating................................................5-36
Overspeed Warning Light..............................3-39
Reduced Power Light...................................3-41
Shutdown Warning Light...............................3-39
Starting Your Diesel.....................................2-14
Starting Your DURAMAX™ Diesel..................2-19
Starting Your Gasoline..................................2-12
Engine Alarm and Automatic Shutdown..............2-16
Engine Coolant Level Check.............................6-24
Engine Cooling System Service........................6-26
Engine Cover Check.......................................6-28
Engine Oil Additives................................5-23, 5-29
Engine Oil Level Check...................................6-24
Engine Road Speed Governor..........................3-25
Engine Speed Limiting.....................................3-25
Engine Starter Over-Crank Protection.................2-12
Event Data Records (EDR)................................ 7-5
Exhaust Brake Indicator Light...........................3-40
5