GM Cutlass RWD 1970-1987 Repair Guide

Transmission

Print

FLUID RECOMMENDATIONS



In all manual transmissions use only standard GL-5 hypoid gear oil - SAE 80W or SAE 80W/90.

In all automatic transmissions use only DEXRON ll® or superceding fluid

LEVEL CHECK



Manual Transmission
  1. Raise and support the vehicle with jackstands, preferably in a level attitude. Remove the filler plug from the side of the transmission housing.
  2.  
  3. If the lubricant begins to trickle out of the hole, there is enough and you need not go any further. Otherwise, carefully insert your finger (watch out for sharp threads) and check to see if the oil is up to the edge of the hole.
  4.  
  5. If not, add oil through the hole until the level is at the edge of the hole. Most gear lubricants come in a plastic squeeze bottle with a nozzle; making additions simple. You can also use a common kitchen baster. Use only standard GL-5 hypoid-type gear oil-SAE 80W or SAE 80W/90.
  6.  
  7. Replace the filler plug and lower the vehicle
  8.  
  9. Drive the car and check for leaks.
  10.  

Automatic Transmission

See Figures 1, 2, 3 and 4



Click image to see an enlarged view

Fig. Fig. 1: After the transmission has reached normal operating temperature, remove the dipstick and check the fluid level



Click image to see an enlarged view

Fig. Fig. 2: Add the proper type and amount of fluid



Click image to see an enlarged view

Fig. Fig. 3: After the engine has been started and the transmission put through the gears, recheck the fluid level



Click image to see an enlarged view

Fig. Fig. 4: Automatic transmission dipstick marks; the proper level is within the shaded area

Always use DEXRON ll®(ATF) or equivalent. The use of Type F (ATF) or any other fluid will cause severe damage to the transmission.

The fluid level should be checked only when the transmission is hot (normal operating temperature). The transmission is considered hot after about 20 miles of highway driving.

  1. Park the car on a level surface with the engine idling. Shift the transmission into park and set the parking brake.
  2.  
  3. Remove the dipstick, wipe it clean and then reinsert it firmly. Be sure that it has been pushed all the way in. Remove the dipstick again and check the fluid level while holding it horizontally. With the engine running, the fluid level should be between the second notch and the FULL HOT line. If the fluid must be checked when it is cool, the level should be between the first and second notches.
  4.  
  5. If the fluid level is below the second notch (engine hot) or the first notch (engine cold), add DEXRON ll® automatic transmission fluid through the dipstick tube. This is easily done with the aid of a funnel. Check the level often as you are filling the transmission. Be extremely careful not to overfill it. Overfilling will cause slippage, seal damage and overheating. Approximately one pint of automatic transmission fluid will raise the fluid level from one notch/line to the other.
  6.  

The fluid on the dipstick should always be a bright red color. If it is discolored (brown or black), or smells burnt, serious transmission troubles, probably due to overheating, should be suspected. The transmission should be inspected by a qualified technician to locate the cause of the burnt fluid.

DRAINING & REFILLING



Manual Transmission

There is no recommended interval for the manual transmission but it is always a good idea to change the fluid if you have purchased the car used or if it has been driven in water high enough to reach the axles.

  1. The oil must be hot before it is drained. Drive the car until the engine reaches normal operating temperature.
  2.  
  3. Raise the vehicle and support it with jackstands. Remove the filler plug to provide a vent.
  4.  
  5. Place a large container underneath the transmission and then remove the drain plug.
  6.  
  7. Allow the oil to drain completely. Clean off the drain plug and replace it; tighten it until it is just snug.
  8.  
  9. Fill the transmission with the proper lubricant as detailed earlier in this section. Refer to the Capacities chart for the correct amount of lubricant.
  10.  
  11. When the oil level is up to the edge of the filler hole, replace the filler plug and lower the vehicle. Drive the car for a few minutes, stop, and check for any leaks.
  12.  

Automatic Transmission

See Figures 5, 6, 7, 8, 9 and 10

The transmission will be equipped either with a replaceable filter or a strainer which must be cleaned. Turbo 400 transmissions will have a filter. All others may have either a filter or a strainer.

  1. The fluid should be changed with the engine warm. Raise and support the vehicle with jackstands.
  2.  
  3. Place a large pan under the transmission. Remove all the front and side bolts. Loosen the rear bolts about four turns. Pry or tap the pan loose and let it drain.
  4.  
  5. Remove the rear bolts, the pan and also the gasket. Clean the pan thoroughly with solvent and dry it with a clean rag. Be very careful not to get any lint from rags in the pan.
  6.  



Click image to see an enlarged view

Fig. Fig. 5: Remove the pan bolts and carefully tap or pry the pan loose



Click image to see an enlarged view

Fig. Fig. 6: Remove the old gasket

  1. Remove the strainer-to-valve body screws, the strainer and the gasket. On the 400 transmission, remove the filter retaining bolt, filter, and intake pipe O-ring. If there is a strainer, clean it in solvent and air dry it.
  2.  
  3. Install the new filter or cleaned strainer with a new gasket. On the Turbo 400, install a new intake pipe O-ring along with a new filter.
  4.  
  5. Install the pan with a new gasket. Tighten the bolts evenly to 10-13 ft. lbs. (13-17.5 Nm)
  6.  



Click image to see an enlarged view

Fig. Fig. 7: Install transmission filter gasket



Click image to see an enlarged view

Fig. Fig. 8: Install the new transmission filter



Click image to see an enlarged view

Fig. Fig. 9: Install the pan with a new gasket

  1. Lower the car and add five pints of DEXRON®II automatic transmission fluid through the dipstick tube.
  2.  
  3. Start the engine and let it idle in Park. Do not race the engine. Shift through each of the gears, then shift back to Park. Check the fluid level on the dipstick. The fluid level will probably be one pint low. Add fluid as necessary. Do not overfill the transmission.
  4.  
  5. Drive the car long enough to thoroughly warm up the transmission. Recheck the fluid level and add fluid as necessary.
  6.  



Click image to see an enlarged view

Fig. Fig. 10: Identifying automatic transmission by pan gasket

 
label.common.footer.alt.autozoneLogo