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.
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