Page 384 of 417

Scheduled Maintenance
7-6Engine Oil and Chassis Lubrication
Scheduled Maintenance
Change engine oil and filter as indicated by the
GM Oil Life System (or every 12 months,
whichever occurs first). Reset the system. The system
will show you when to change the oil
-- usually between
3,000 miles (5 000 km) and 10,000 miles (16 000 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 10,000 miles
(16 000 km) or 12 months without an oil and
filter change.The system won't detect dust in the oil. So if you drive in
a dusty area, be sure to change your oil and filter every
3,000 miles (5 000 km) or sooner if the CHANGE
ENGINE OIL message appears. Remember to reset
the Oil Life System when the oil and filter have been
changed. See ªOil Life Systemº in the Index for
information on resetting.
An Emission Control Service.
Lubricate chassis components with each engine oil and
filter change. Lubricate the front suspension, ball joints,
steering linkage, transmission shift linkage, transfer case
shift linkage, parking brake cable guides, and brake
front axle. Ball joints should not be lubricated unless
their temperature is 10F (
-12C) or higher,
or they could be damaged.
Page 397 of 417

7-19
Starter Switch Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. See ªParking Brakeº in the Index if necessary.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.Automatic Transmission Shift Lock Control
System Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room around
the vehicle. It should be parked on a level surface.
2. Firmly apply the parking brake. See ªParking Brakeº
in the Index if necessary.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the key to the RUN
position, but don't start the engine. Without applying
the regular brake, try to move the shift lever out of
PARK (P) with normal effort. If the shift lever
moves out of PARK (P), your vehicle needs service.
Page 398 of 417

7-20
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK in each shift lever position.
The key should turn to LOCK only when the shift
lever is in PARK (P).
The key should come out only in LOCK.
Parking Brake and Automatic Transmission
PARK (P) Mechanism Check
CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in case
it begins to roll. Be ready to apply the regular
brake at once should the vehicle begin to move.
Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake,
set the parking brake.
To check the parking brake's holding ability:
With the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure
from the regular brake pedal. Do this until the
vehicle is held by the parking brake only.
To check the PARK (P) mechanism's holding
ability: With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care
to clean thoroughly any areas where mud and other
debris can collect.
Page 400 of 417
7-22 Transfer Case and Front Axle
(All-Wheel Drive) Inspection
Every 12 months or at engine oil change intervals,
check front axle and transfer case and add lubricant
when necessary. A fluid loss could indicate a problem;
check and have it repaired, if needed. Check vent hose
at transfer case for kinks and proper installation.
Brake System Inspection
Inspect the complete system. 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 other brake parts,
including calipers, parking brake, etc. You may need to
have your brakes inspected more often if your driving
habits or conditions result in frequent braking.