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How This Section is Organized
This maintenance schedule is divided into four parts:
“Part A: Scheduled Maintenance Services”explains
what to have done and how often. Some of these
services can be complex, so unless you are technically
qualified and have the necessary equipment, you
should let your GM dealer’s service department do
these jobs.
Your GM dealer has GM-trained and supported service
people that will perform the work using genuine GM parts.
{CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you
can be seriously injured. Do your own
maintenance work only if you have the
required know-how and the proper tools and
equipment for the job. If you have any doubt,
have a quali ed technician do the work. See
Doing Your Own Service Work on page 5-4.
If you want to purchase service information, seeService
Publications Ordering Information on page 7-11.“Part B: Owner Checks and Services”tells you what
should be checked and when. It also explains what
you can easily do to keep your vehicle in good condition.
“Part C: Recommended Fluids and Lubricants”
lists some recommended products necessary to help
keep your vehicle properly maintained. These products,
or their equivalents, should be used whether you do
the work yourself or have it done.
“Part D: Maintenance Record”is a place for you to
record and keep track of the maintenance performed on
your vehicle. Keep your maintenance receipts. They
may be needed to qualify your vehicle for warranty
repairs.
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Part A: Scheduled Maintenance
Services
In this part are scheduled maintenance services which
are to be performed at the mileage intervals specified.
Using the Maintenance Schedule
We at General Motors want to help keep your vehicle in
good working condition. But we do not know exactly
how you will drive it. You may drive very short distances
only a few times a week. Or you may drive long
distances all the time in very hot, dusty weather. You
may use your vehicle in making deliveries or in
many other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements. So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your dealer.
This part tells you the maintenance services you should
have done and when to schedule them.
When you go to your dealer for your service needs, you
will know that GM-trained and supported service
people will perform the work using genuine GM parts.The proper fluids and lubricants to use are listed in
Part C. Make sure whoever services your vehicle uses
these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the
vehicle.
This schedule is for vehicles that:
•carry passengers and cargo within recommended
limits. You will find limits on your vehicle’s GVW
Rating label. SeeLoading Your Vehicle on
page 4-34.
•are driven on reasonable road surfaces within legal
driving limits.
•use the recommended fuel. SeeGasoline Octane
on page 5-6for gasoline engine vehicles orWhat
Fuel to Use on page 5-8for diesel engine vehicles.
Scheduled Maintenance
Supplements
If your vehicle has a Caterpillar®diesel engine, your
owner’s manual is supplemented by the Caterpillar®
Diesel Engine Operation & Maintenance Manual. If your
vehicle has an Allison Transmission®, your owner’s
manual is supplemented by an Allison Transmission®
Operator’s Manual. Always refer to these manuals
for related maintenance services.
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Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown after 100,000 miles
(166 000 km) should be repeated at the same miles (km)
after those intervals for the life of this vehicle.
Gasoline engine vehicles and some DURAMAX
®diesel
engine vehicles have a computer that lets you know
when to change your engine oil. This is not based
on mileage, but on engine operation and engine
temperature. When the computer has calculated that the
oil needs changing, the Engine Oil Life System will
indicate that a change is necessary. SeeEngine Oil Life
System (Gasoline Engine) on page 5-31orEngine Oil
Life System (DURAMAX
®Diesel) on page 5-33or
Engine Oil Life System (Caterpillar®Diesel Engine) on
page 5-34.
The “Footnotes” at the end of this Maintenance
Schedule further explain maintenance services.
SeeService Publications Ordering Information on
page 7-11.
100 Miles (160 km)
❑Wheel stud nut service.(36)
1,000 Miles (1 600 km)
❑Wheel stud nut service.(36)
❑Rear axle air shift motor service.(10)
7,500 Miles (12 000 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)
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❑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)
12,000 Miles (20 000 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)
15,000 Miles (24 000 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 5-35
for more information.
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❑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 5-35for 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)
❑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).
22,500 Miles (36 000 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)
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❑Inspect door hinge pins and bushings and replace as
necessary.
❑Cooling system service. Clean the cooling system
filter 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.
❑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)
❑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) †
❑Rear axle air shift motor service.(10)
24,000 Miles (40 000 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).
6-8
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30,000 Miles (48 000 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: 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 5-35
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. See
Engine Air Cleaner/Filter on page 5-35for 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)
❑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)
❑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).
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❑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)
❑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)
❑Air compressor dry element pleated paper air
strainer service (or every 2 months or every
800 hours, whichever occurs first).
36,000 Miles (55 000 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)
37,500 Miles (60 000 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)
6-10