2001 GMC SIERRA AC system

7-21
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.
NOTE: Do not use the accelerator pedal, and be
ready to turn off the engine immediately if it starts.
3. On automatic transmission vehicles, 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.
On manual transmission vehicles, put the shift lever
in NEUTRAL (N), push the clutch down halfway
and try to start the engine. The starter should work
only when the clutch is pushed down all the way to
the floor. If the starter works when the clutch isn't
pushed all the way down, 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.
NOTE: 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.

7-23
Part C: Periodic
Maintenance Inspections
Listed in this part are inspections and services which
should be performed at least twice a year (for instance,
each spring and fall). You should let your dealer's
service department or other qualified service center
do these jobs. Make sure any necessary repairs are
completed at once.
Proper procedures to perform these services may be
found in a service manual. See ªService and Owner
Publicationsº in the Index.
Steering and Suspension Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook
-up, binding, leaks,
cracks, chafing, etc.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the
body near the exhaust system. Look for broken,
damaged, missing or out
-of-position parts as well as
open seams, holes, loose connections or other conditions
which could cause a heat build
-up in the floor pan or
could let exhaust fumes into the vehicle. See ªEngine
Exhaustº in the Index.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser.
To help ensure proper operation, a pressure test of the
cooling system and pressure cap is recommended at
least once a year.

7-24 Throttle System Inspection
Inspect the throttle system for interference or binding,
and for damaged or missing parts. Replace parts as
needed. Replace any components that have high effort
or excessive wear. Do not lubricate accelerator and
cruise control cables.
Transfer Case and Front Axle
(Four-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. On manual
shift transfer case, oil the control lever pivot point.
Check vent hose at transfer case for kinks and proper
installation. More frequent lubrication may be required
on off
-road use.
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.

7-25
Part D: Recommended Fluids
and Lubricants
NOTE: Fluids and lubricants identified below by name,
part number or specification may be obtained from
your dealer.
USAGE
FLUID/LUBRICANT
Engine OilEngine oil with the American
Petroleum Institute Certified
for Gasoline Engines starburst
symbol of the proper viscosity.
To determine the preferred
viscosity for your vehicle's engine,
see ªEngine Oilº in the Index.
Engine Coolant50/50 mixture of clean,
drinkable water and use only
GM Goodwrench

DEX-COOL

or Havoline
DEX-COOL

Coolant. See ªEngine Coolantº
in the Index.
Hydraulic
Brake SystemDelco Supreme 11
Brake Fluid
(GM Part No. 12377967 or
equivalent DOT
-3 brake fluid).
USAGEFLUID/LUBRICANT
Windshield
Washer SolventGM Optikleen
Washer Solvent
(GM Part No. 1051515)
or equivalent.
Hydraulic
Clutch SystemHydraulic Clutch Fluid
(GM Part No. 12345347 or
equivalent DOT
-3 brake fluid).
Power Steering
SystemGM Power Steering Fluid
(GM Part No. 1052884
- 1 pint,
1050017
- 1 quart, or equivalent).
Manual
Transmission
(5
-Speed with
Low Gear,
RPO MW3)
GM Goodwrench Synthetic
Manual Transmission Fluid
(GM Part No. 12346190
- 1 qt.)
or equivalent SAE 75W
-85 GL-4
gear oil.
Manual
Transmission
(5
-Speed without
Low Gear,
RPO MG5)
Synchromesh Transmission Fluid
(GM Part No. 12345349
or equivalent).
Manual
Transmission
(6
-Speed)
TranSynd Synthetic Automatic
Transmission Fluid
(GM Part No. 12378515).