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If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the API service symbol are all you will need for
good performance and engine protection.
Engine Oil Life System
(Gasoline Engine)
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A change engine oil light will come on. See
Change Engine Oil Light on page 3-40. Change your
oil as soon as possible within the next 600 miles
(1 000 km). It is possible that, if you are driving under
the best conditions, the oil life system may not indicate
that an oil change is necessary for over a year.
However, your engine oil and filter must be changed at
least once a year and at this time the system must
be reset. Your dealer has GM-trained service people
who will perform this work using genuine GM parts and
reset the system. It is also important to check your
oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
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Page 338 of 398

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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