How to Change Fluids During Transmission Repair

Most car manufacturers and transmission repair shops will recommend that you change your fluid and filter every 20,000 to 25,000 miles. It can get quite expensive to have your fluids replaced at a transmission repair shop if you have never had it done before.

There are two ways that you can do this. One way is to pump out the old fluids prior to adding the new ones. The second way does not require any pumping but it does leave some of the old fluid to be mixed in with the new one. As far as tools, you will need a transmission filter service kit. This kit has the filter and pan gasket. In addition, you will need a drain pan along with 3 to 6 quarts of trans fluid. You will also need a funnel, screwdrivers, mallet, socket wrenches, brake cleaner, rags, jack or car ramps, a couple of empty juice or milk containers and wheel chokes.

You will need to prepare your vehicle before doing a fluid change. Fluid changes need to be done when the car is at normal temperatures. Either jack up your car or put your car up on car ramps. Turn your car on and allow your engine to idle for about 5 to 10 minutes and then turn it off. While the fluid is warm, it is time to remove the old fluid. Place a drain pan underneath the location of the fluid dipstick. Now you can drain the fluid by removing the drain plug. After you have noticed that most of the fluid has been drained, remove the drain pan and transfer the fluids into the empty containers.

Take off the old filter. The filter is attached to the trans with clips, O-ring seal or bolts. You do not have to clean the filter because all you're going to do is throw it away. Prior to adding new fluid, the trans pan will need to be cleaned using a rag. Now remove any parts of the gasket that may be along the pan edges. After the pan and bolts have dried, you can install the new transmission filter. Be sure that it is mounted in the correct position and that the O-ring is positioned properly. Replace any bolts or clips that you took off and be sure that they are securely fastened to the filter. You can now put back the transmission pan using the gaskets. Most gaskets are self sealing. You can now add the new fluid. Most vehicles let you add the new fluid where the dipstick is located by using a funnel. After you have added the fluid, start the car and let it idle for at least 2 minutes. Apply the parking and service breaks, and move the gear selector through each of the positions and ending in the park position. Check and recheck the fluid levels to be sure that you have enough fluid. Run the car until it reaches a normal temperature for operation and then check the fluid levels again.

Once you have mastered the art of changing your fluids, you can keep your vehicle healthy by taking it to the transmission repair shop for regular maintenance.