How to Change the Fluid in a Powerglide Transmissionby Jhonna Moye
General Motors developed the Powerglide transmission in 1950. It came standard in Chevrolet vehicles until the early 1970s. You should change the fluid every 24,000 miles or two years, whichever comes first. If regular fluid checks show the transmission fluid to be anything but bright red, you should change the fluid at that time, regardless of the mileage or amount of time that has passed.
Drain the transmission fluid by removing the drain plug. Most Powerglide transmissions have a drain plug located on the outer edge of the pan. Place a container on the ground or floor under the transmission that is big enough to catch about 4 quarts of transmission fluid. Loosen and remove the drain plug by turning counterclockwise with a socket wrench. Allow all of the transmission fluid to drain. If no plug is present, locate the bolts holding the pan onto the unit. Place a container wider and longer than the transmission on the floor or ground under the transmission and using a socket wrench, loosen the bolts to drain the transmission fluid.
Remove the transmission pan by removing the bolts holding it onto the unit with a socket wrench and a counterclockwise motion. This will allow access to the filter. Pour any remaining transmission fluid into the container.
Unscrew the two screws that hold the filter on the unit. Use a flat-headed screwdriver and turn counterclockwise. Discard the used filter and filter gasket.
Attach a new filter. Hold the filter in place while using a clockwise turning motion with the flat-headed screwdriver to tighten the two screws in place.
Clean the transmission pan. Using a dry cloth, remove all debris and transmission oil residue.
Straighten the gasket flange. This part is located on the transmission, where the pan comes in contact with the unit. Gently tap the gasket flange with a light-duty hammer until it is in place.
Replace the transmission pan using a new filter gasket. Apply a small amount of RTV sealer on the gasket. Place the gasket on the transmission pan. Insert all transmission pan bolts by holding the transmission pan in place with one hand and using the other hand to place the bolts. While still holding the pan in place with one hand, tighten the bolts using a socket wrench. For the gasket to seal properly, alternate partial tightening of each bolt until all bolts have been completely tightened.
Fill the transmission with transmission fluid. Consult your vehicle owner's manual for information regarding the amount and type of fluid to use.
Start the vehicle and, while depressing the brake, move the gear shifter to each position. Allow it to remain in one position for several seconds before shifting to another. This ensures that the transmission fluid refills the transmission circuits.
Check the transmission fluid level. Start the vehicle and allow it to reach normal operating temperature. Shift the vehicle to the "Neutral" position and engage the Emergency Brake. With the vehicle still running, remove the transmission fluid dipstick and inspect the amount of fluid present on the dipstick. Add fluid if necessary.
- Park the vehicle on a flat, level surface so that the old transmission fluid will drain properly.
- Do not position your head directly under the transmission when fluid is still in the transmission.
- Do not dispose of old transmission fluid by pouring down drains or onto the ground.
Items you will need
- Socket wrench
- Large container
- Flat-headed screwdriver
- Filter gasket
- Clean, dry cloth
- Light-duty hammer
- RTV sealer
- "Powerglide Transmission Handbook;" Carl H. Munroe; 2001
- Popular Mechanics; "Changing Your Transmission Fluid;" Bob Freudenberger; June 2003