GM Service Manual Online
For 1990-2009 cars only

The cause of most external leaks can generally be located and repaired with the transaxle in the vehicle.

Transaxle Fluid Level Service Procedure

This procedure is to be used when checking a concern with the fluid level in a vehicle. A low fluid level will result in slipping and loss of drive/reverse or delay on engagement of drive/reverse when the vehicle is cold.

The vehicle is first checked for transaxle diagnostic messages on the scan tool. If the oil level is low, it is possible to register a vehicle speed signal fault.

The vehicle is to be test driven to determine if there is an abnormal delay when selecting drive or reverse, or loss of drive. One symptom of low fluid level is a momentary loss of drive when driving the vehicle around a corner. Also when the transaxle fluid level is low, a loss of drive may occur when the transaxle fluid temperature is low.

When adding or changing transaxle fluid use only ESSO LT 71141or ISU H50235 automatic transaxle fluid or other approved fluids. The use of incorrect fluid will cause the performance and durability of the transaxle to be severely degraded.

Fluid Level Diagnosis Procedure

  1. If the vehicle is at operating temperature allow the vehicle to cool down for 2 hours, but no greater than 4 hours. Or if the vehicle is at cool status, start the engine and allow the engine to idle for approximately 5 minutes (825-875 RPM). If possible, drive the vehicle for a few kilometers (miles), N-D, N-R, shift until two gear. This will allow the transaxle to be within the correct temperature range. The transaxle fluid level should be checked at temperature 20-45°C (68-113°F).
  2. Caution: When the transmission is at operating temperatures, take necessary precautions when removing the check/fill plug, to avoid being burned by draining fluid.

  3. Switch OFF/accessories, especially the air conditioner, heater.
  4. With the brake pedal pressed, move the gear shift control lever through the gear ranges, pausing a few seconds in each range. Return the gearshift lever to park (P). Turn the engine OFF.
  5. Park the vehicle on a hoist, inspection pit, or similar raised level surface. The vehicle must be level to obtain a correct fluid level measurement.
  6. Place a fluid container below the fluid filler plug.
  7. Clean all dirt from around the fluid filler plug. Remove the fluid filler plug. Clean the filler plug and inspect that there is no damage to the O-ring.
  8. • If fluid drains through the filler hole the transaxle may have been overfilled. When the fluid stops draining the fluid level is correct. Install the fluid filler plug and tighten it to 45 N·m (33 lb ft).
    • If fluid does not drain through the filler hole, the transaxle fluid level may be low. Lower the vehicle, and start the vehicle in park (P) with the parking brake and the brake applied. With the engine idling, move the gear shift lever through the gear ranges, pausing a few seconds in each range and adding the fluid until gear application is felt. Return the gear shift lever to park (P). Turn the engine OFF and raise the vehicle. Check if the fluid level is aligned with the bottom of the filler hole. If not, add a small quantity of fluid to the correct level. Install the fluid filler plug and tighten it to 45 N·m (33 lb ft).
  9. When the fluid level inspection procedure is completed, wipe any fluid around the filler plug with a rag or shop towel.

Fluid Level Set After Service

  1. Depending on the service procedure performed, add the following amounts of fluid through the filler plug hole prior to adjusting the fluid level:
  2. • Oil pan removal - 4 liters (4.23 quarts)
    • Converter removal - 2 liters (2.11 quarts)
    • Overhaul - 6.9 liters (7.3 quarts) - 2.0 DOHC
    • Overhaul - 7.4 liters (7.8 quarts) - 2.5 DOHC
    • Oil drain plug removal - 4 liters (4.23 quarts)
  3. Follow steps 1-4 of the Fluid Level Diagnosis Procedure.
  4. Clean all dirt from around the fluid filler plug. Remove the fluid filler plug. Clean the filler plug and check that there is no damage to the O-ring.
  5. Lower the vehicle with the filler plug still removed and start the vehicle in park (P) with the parking brake and the brake applied. With the engine idling, move the gear shift lever through the gear ranges, pausing a few seconds in each range and adding the fluid until gear application is felt. Then add an additional 0.5 liters (0.53 quarts) of fluid. Return the gear shift lever to park (P). Turn the engine OFF and raise the vehicle. Install the fluid filler plug and tighten it to 45 N·m (33 lb ft).
  6. Drive the vehicle at 3.5-4.5 km (2.2-2.8 mi) with light throttle so that the engine does not exceed 2,500 RPM. This should result in the transaxle temperature being in the range 20-45°C (68-113°F). With the brake applied, move the shift lever through the gear ranges, pausing a few seconds in each range at the engine idling.
  7. Return the gear shift lever to park (P). Turn the engine OFF and raise the vehicle on the hoist, if applicable, ensuring the vehicle is level. When the 3 minutes passed after the engine stopped, remove the filler plug. Check if the fluid level is aligned with the bottom of the filler hole. If not, add a small quantity of fluid to the correct level. Install the fluid filler plug and tighten it to 45 N·m(33 lb ft).
  8. Wipe any fluid around the filler plug with a rag or shop towel.

Methods for Locating Leaks

General Method

  1. Verify that the leak is transaxle fluid.
  2. Thoroughly clean the suspected leak area.
  3. Drive the vehicle for approximately 25 km (15 mi) or until the transaxle reaches normal operating temperature 88°C (190°F).
  4. Park the vehicle over clean paper or cardboard.
  5. Turn the engine OFF and look for fluid spots on the paper.
  6. Make the necessary repairs to correct the leak.

Powder Method

  1. Thoroughly clean the suspected leak area.
  2. Apply an aerosol type powder foot powder to the suspected leak area.
  3. Drive the vehicle for approximately 25 km (15 mi) or until the transaxle reaches normal operating temperature 88°C (190°F).
  4. Turn the engine OFF.
  5. Inspect the suspected leak area and trace the leak path through the powder to find the source of the leak.
  6. Make the necessary repairs.

Dye and Black Light Method

  1. Add dye to the transaxle though the transaxle fluid filler plug. Follow the manufacturer's recommendation for the amount of dye to be used.
  2. Use the black light to find the fluid leak.
  3. Make the necessary repairs.

Repairing the Fluid Leak

Once the leak point is found, the source of the leak must be determined. The following list describes the potential causes for the leak:

    • The fasteners are not torqued to specification.
    • The fastener threads and fastener holes are dirty or corroded.
    • The gaskets, seals, or sleeves are misarranged, damaged, or worn.
    • Damaged, warped, or scratched seal bore or gasket surface
    • Loose or worn bearing causing excess seal or sleeve wears
    • Case or component porosity
    • The fluid level is too high.
    • Plugged vent or damaged vent tube
    • Water or coolant in fluid
    • Fluid drain back holes plugged