GM Cavalier/Sunbird/Skyhawk/Firenza 1982-1994

Manual Transaxle



All 4-speed manual transaxles use Dexron® III or IIE (or the latest superceding fluid grade) automatic transmission fluid, which is a thin, reddish fluid. All 5-speeds through 1987 use 5W-30 engine oil. 1988-94 5-speed manual transaxles use Synchromesh® transmission fluid, GM part no. 12345349.

Using the incorrect lubricant in your transaxle can lead to significant transaxle damage and a costly overhaul.


See Figures 1, 2, 3 and 4

The fluid level in the manual transaxle should be checked every 12 months or 7,500 miles (12,000 km), whichever comes first.

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Fig. Fig. 1: Location of the manual transaxle dipstick and filler tube - 1984 5-speed shown, 4-speed similar

  1. Park the car on a level surface. The transaxle should be cool to the touch. If it is hot, check the level later, when it has cooled.
  3. Remove the dipstick from the transaxle.

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Fig. Fig. 2: Remove the dipstick from the transaxle

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Fig. Fig. 3: Check the fluid level of the transaxle with the marks on the dipstick

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Fig. Fig. 4: If the fluid level is low, add it through the filler tube until the level is correct. Make sure not to add too much fluid

  1. Check the level with the marks located on the dipstick.
  3. If lubricant is needed, add it through the filler tube until the level is correct. When the level is correct, reinstall the dipstick firmly.

The dipstick must be fully seated in the filler tube during vehicle operation or leakage will occur at the vent plug.


Under normal conditions, the manual transaxle fluid does not need to be changed. However, if the car is driven in deep water (as high as the transaxle casing) it is a good idea to replace the fluid. Little harm can come from a fluid change when you have just purchased a used vehicle, especially since the condition of the transaxle is usually not known.

If the fluid is to be drained, it is a good idea to warm the fluid first so it will flow better. This can be accomplished by 15-20 miles (24-32 km) of highway driving. Fluid which is warmed to normal operating temperature will flow faster, drain more completely and remove more contaminants from the housing.

  1. Remove the filler plug (or dipstick) from the left side of the transaxle to provide a vent.
  3. Raise and support the vehicle safely using jackstands.
  5. The drain plug is located on the bottom of the transaxle case. Place a pan under the drain plug and remove it.

The fluid will be HOT. Push up against the threads as you unscrew the plug to prevent leakage.

  1. Allow the fluid to drain completely. Check the condition of the plug gasket and replace it if necessary. Clean off the plug and replace, tightening it until snug.
  3. Fill the transaxle with fluid through the fill or dipstick tube. You will need the aid of a long neck funnel or a funnel and a hose to pour through.
  5. Use the dipstick to gauge the level of the fluid.
  7. Replace the filler plug or dipstick and dispose of the old fluid in the same manner as you would old engine oil.

Take a drive in the car, stop on a level surface, and check the oil level.