75,000 Miles (120 000 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)
❑6.6L DURAMAX
®Diesel Without Engine Oil Life
System Only: Change engine oil and filter (or every
12 months, or every 750 hours of engine operation,
whichever occurs first).(2)
❑6.6L DURAMAX
®Diesel With Engine Oil Life System
Only: Check oil life system. If engine oil and filter are
changed, reset system. See “Engine Oil (DURAMAX
®
Diesel)” in the Index.(2) (9)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (5)
❑Gasoline Engine: Inspect engine air cleaner filter. If
necessary, replace the filter. If vehicle is driven in
dusty/dirty conditions, inspect filter at every engine oil
change. SeeEngine Air Cleaner/Filter on page 5-33
for more information.
❑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. SeeEngine Air
Cleaner/Filter on page 5-33for more information.❑DURAMAX
®Diesel Only: Replace fuel filter (or every
750 hours of engine operation, whichever occurs first).
❑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)
❑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)
❑Fuel tank, fuel cap and fuel lines service (or every
72 months, whichever occurs first).(2) (26) †
6-16
❑EGR system inspection (if equipped) (or every
72 months, whichever occurs first).(2) (27)
❑Thermostatically controlled engine cooling fan
service.(3) (19)
❑Shields and underhood insulation service.(3) (4) (20)
❑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 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)
❑Wheel bearings service — Eaton®axle, oil-filled, (or
every 24 months, whichever occurs first).(22) (36)
84,000 Miles (140 000 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 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)
6-17
90,000 Miles (144 000 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)
❑6.6L DURAMAX
®Diesel Without Engine Oil Life
System Only: Change engine oil and filter (or every
12 months, or every 750 hours of engine operation,
whichever occurs first).(2)
❑6.6L DURAMAX
®Diesel With Engine Oil Life System
Only: Check oil life system. If engine oil and filter are
changed, reset system. See “Engine Oil (DURAMAX
®
Diesel)” in the Index.(2) (9)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (5)
❑Gasoline Engine: Replace engine air cleaner filter.
SeeEngine Air Cleaner/Filter on page 5-33for more
information.
❑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. SeeEngine Air
Cleaner/Filter on page 5-33for more information.
❑DURAMAX
®Diesel Only: Replace fuel filter (or every
750 hours of engine operation, whichever occurs first).
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)❑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).(22) (36)
❑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.
❑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)
6-18
❑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).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 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)
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)
6-19
❑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).
❑Except four-wheel drive: Front axle service.(31)
❑Four-wheel drive only: Front axle service.(30)
❑Four-wheel drive only: Transfer case service.(30)
❑Rear axle service — Eaton
®, Rockwell®, Spicer®
axles (or every 12 months, whichever occurs
first).(30)❑Exhaust brake service, if equipped. Check for
excessive spindle free play and smooth operation.
Lubricate ball joint cap.
❑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).
❑Trailer brake hand control valve service (or every
12 months, or every 3,600 hours, whichever
occurs first).(35)
120,000 Miles (192 000 km)
❑C600, C700, and C800 Gasoline Engines Only:
Replace engine drive belts.
❑C400 and C500 Gasoline Engines Only: Engine drive
belts service (or every 12 months, whichever occurs
first).(17)
150,000 Miles (240 000 km)
❑Cooling system service (or every 60 months since
last service, whichever occurs first).(2) (29)
❑Diesel Engine Only: Inspect engine drive belt;
replace as necessary.
6-20
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.
250,000 Miles (400 000 km)
❑Four-wheel drive only: Front axle service.(30)
❑Four-wheel drive only: Transfer case service.(30)
❑Rear axle service — Eaton
®, Rockwell®, Spicer®
axles (or every 36 months, whichever occurs
first).(30)
❑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 desiccant.
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 Transmission
®, your
GM owner manual is supplemented by an Allison
Transmission
®Operator’s Manual. Always refer to these
manuals for related maintenance services.
(2)= An Emission Control Service.
(3)= A Noise Emission Control Device.
(4)= Applies only to vehicles sold in the United States.
(5)= 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.
6-21
(6)= 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.
(7)= This vehicle has the Engine 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
12,000 miles (20 000 km) since your last oil change.
Under severe conditions, the indicator may come on
before 3,000 miles (5 000 km). Never drive your
7.8L diesel engine vehicle more than 12,000 miles
(20 000 km), or 12 months, or 600 engine hours, without
an oil and filter change.
Remember to reset the Engine Oil Life System
whenever the oil is changed. For more information, see
Engine Oil Life System (Gasoline Engine) on page 5-29
orEngine Oil Life System (DURAMAX
®Diesel) on
page 5-31orEngine Oil Life System (Caterpillar®Diesel
Engine) on page 5-32.
(8)= This vehicle has the Engine 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 gasoline
engine vehicle more than 7,500 miles (12 000 km) or
12 months without an oil and filter change.
Remember to reset the Engine Oil Life System
whenever the oil is changed. For more information, see
Engine Oil Life System (Gasoline Engine) on page 5-29
orEngine Oil Life System (DURAMAX
®Diesel) on
page 5-31orEngine Oil Life System (Caterpillar®Diesel
Engine) on page 5-32.
(9)= This vehicle has the Engine 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
15,000 miles (24 000 km) since your last oil change.
Under severe conditions, the indicator may come on
before 3,000 miles (5 000 km). Never drive your
6.6L diesel engine vehicle more than 15,000 miles
(24 000 km), or 12 months, or 750 engine hours, without
an oil and filter change.
Remember to reset the Engine Oil Life System
whenever the oil is changed. For more information, see
Engine Oil Life System (Gasoline Engine) on page 5-29
orEngine Oil Life System (DURAMAX
®Diesel) on
page 5-31orEngine Oil Life System (Caterpillar®Diesel
Engine) on page 5-32.
6-22
(10)= 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
1,000 miles (1 600 km) and 22,500 miles (36 000 km)
and then every 22,500 miles (36 000 km) thereafter.
(11)= 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. Front axle tie rod ends, both upper and lower
kingpin fittings, and both steering linkage relay rod
ends should be greased with the vehicle loaded on the
ground and wheels turned straight ahead, NOT with
the vehicle on a hoist. Apply kingpin bushing lubricant to
both upper and lower kingpin grease fittings until new
lubricant purges from between the upper shim pack and
thrust bearing. 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, clutch pedal springs, and clutch cable bushing at
transmission. Lubricate suspension, axle, and steering
linkage more often when operating under dusty or
muddy conditions and in excessive off-road use.
Frequently power-washed vehicles will require more
frequent lubrication.(12)= Check steering system:
•Look for damaged, loose, or missing parts. Inspect
the steering linkage relay rod and tie rod ends for
looseness or lack of lubricant. 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 the 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.
(13)= 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.
6-23