GM Service Manual Online
For 1990-2009 cars only

At Each Fuel Fill

It is important to perform these underhood check at each fuel fill.

The following information covers the checks and services required to retain the safety, dependability, and emission control performance of the vehicle.

Make sure any necessary repairs are completed on time. Whenever any fluids or lubricants are added to the vehicle, make sure that they are the proper ones. Refer to Fluid and Lubricant Recommendations .

Engine Oil Level

Check the engine oil level and add the proper oil if necessary. In order to select the proper fluids and lubricants, refer to Fluid and Lubricant Recommendations .

Engine Coolant Level

Check the engine coolant levels and add DEX-COOL® coolant mixture if necessary. Refer to Fluid and Lubricant Recommendations .

Windshield Washer Fluid Level

Check the windshield washer fluid level in the windshield washer tank and add the proper fluid if necessary. Refer to Fluid and Lubricant Recommendations .

At Least Once a Month

Tire Inflation

Check tire inflation. Make sure the tires are inflated to the pressures specified on the Certification/Tire label located on the driver's door lock pillar. Refer to Vehicle Certification Label .

Cassette Deck

Clean the playback heads and capstan on the cassette deck. Cleaning should be done every 50 hours of tape play.

At Least Twice a Year

Restraint System Check

Make sure the seat belt reminder light and all the belts, buckles, latch plates, retractors and anchorages are working properly. Look for any other loose or damaged safety belt system parts. If you see anything that might keep a safety belt system from doing its job, have it repaired. Have any torn or frayed safety belts replaced.

For seat belt diagnosis information, refer to Operational and Functional Checks in Seat Belts.

Also look for any opened or broken Supplemental Inflatable Restraint (SIR) covers. (The SIR system does not need regular maintenance.)

For SIR Diagnosis refer to Diagnostic Starting Point - SIR in SIR.

Wiper Blade Check

Inspect wiper blades for wear or cracking. Replace blade inserts that appear worn, cracked, damaged or that streak or miss areas of the windshield. Refer to Windshield Wiper Blade Replacement in Wipers/Washer Systems.

Spare Tire Check

At least twice a year, after the monthly inflation check of the spare tire determines that the spare is inflated to the correct tire inflation pressure, make sure that the spare tire is stored securely. Push, pull, and then try to rotate or turn the tire. If it moves, use the wheel wrench to tighten the cable.

Weatherstrip Lubrication

Silicone grease on weatherstrips will make them last longer, seal better, and not stick or squeak. Apply silicone grease with a clean cloth.

During very cold, damp weather more frequent application may be required. Refer to Fluid and Lubricant Recommendations .

Manual Transmission Check

Check the transmission fluid level; add if needed. Refer to Fluid and Lubricant Recommendations . For the NV1500 manual transmission, refer to Fluid Replacement .

For the NV3500 manual transmission, refer to Fluid Replacement .

Automatic Transmission Check

Check the transmission axle fluid level; add if needed. Refer to Fluid and Lubricant Recommendations .

A fluid loss may indicate a problem. Check the system and repair if needed.

For the 4L60-E fluid lever inspection refer to Transmission Fluid Check . If fluid was added, refer to Fluid Leak Diagnosis .

Hydraulic Clutch System Check

Check the fluid level in the clutch reservoir. Refer to Fluid and Lubricant Recommendations . A fluid loss in this system could indicate a problem. Check the system and repair if needed.

At Least Four Times a Year

Tailgate Lubrication Service

Lubricate the tailgate latch bolt, handle assembly pivot points, and hinges with lubricant. Refer to Fluid and Lubricant Recommendations .

At Least Once a Year

Key Lock Cylinders

Lubricate the lock cylinders with the recommended lubricant. Refer to Fluid and Lubricant Recommendations .

Body Lubrication

Lubricate all of the following areas:

    • Body door hinges
    • Body hood, safety lever, and prop rod pivot
    • Fuel door
    • Rear compartment hinges
    • Rear compartment latches and locks
    • Instrument panel compartment hinges, latch, and lock cylinder
    • Console cover hinges and latch
    • Seat hardware

More frequent lubrication may be required when exposed to a corrosive environment. In order to locate the proper lubricant, refer to Fluid and Lubricant Recommendations .

Starter Switch Check

    • Before you start, ensure that you have enough room around the vehicle in case the vehicle jumps suddenly.

       Important: Do not use the accelerator pedal, and be ready to turn off the engine immediately if it starts.

    • Firmly apply both the park brake and the regular brake.
    • 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, the 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 is not pushed all the way down, the vehicle needs service.

Automatic Transmission Shift Lock Control Check

  1. Before you start, be sure you have enough room around the vehicle. It should be parked on a level surface.
  2. Important: Be ready to apply the regular brake immediately if the vehicle begins to move.

  3. Firmly apply the parking brake.
  4. With the engine off, turn the key to the RUN position, but don't start the engine.
  5. Without applying the regular brake, try to move the shift lever out of PARK (P) with normal effort.
  6. If the shift lever moves out of PARK (P), the vehicle needs service.

Ignition Transmission Lock Check

  1. With the vehicle parked, set the parking brake.
  2. Try to turn the ignition key to LOCK in each shift lever position.
  3. With an automatic transmission, the key should turn to LOCK only when the shift lever is in PARK (P).
  4. With a manual transmission, the key should turn to LOCK only when you press the key release button.
  5. On all vehicles, the key should come out only in LOCK.

Park Brake and Automatic Transmission PARK (P) Mechanism Check

Caution: When performing this check, the vehicle could begin to move. You or others could be injured and property could be damaged. Make sure there is room in front of the vehicle in case the vehicle begins to roll. Be ready to apply the regular brake at once, should the vehicle begin to move.

Follow this procedure to test the park brake and automatic transmission PARK mechanism:

    • Park on a fairly steep hill, with the vehicle facing downhill.
    • Keep your foot on the hydraulic brake pedal.
    • Set the park brake.
    • Check the park brake:
        1. Start the engine.
        2. Place the transmission in NEUTRAL.
        3. Slowly remove foot pressure from the regular brake pedal. If the vehicle moves, refer to Park Brake Adjustment in Park Brake.
    • In order to check the PARK (P) mechanism of an automatic transmission, follow steps 1-3 above then do the following:
        1. Shift to PARK (P).
        2. Release all brakes.

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.