Changing the transmission filter in the Audi A4 is a job that can be completed in less than an hour. The filter on the Audi A4 is located inside the transmission pan, on the underside of the transmission. It is a good idea to change the transmission fluid at the same you change the filter, since the transmission fluid has to be drained anyway. You can change the transmission filter yourself, saving you time and money.
Lift the vehicle with a floor jack and place a jack stand under the front and back axles behind each wheel. Verify that the vehicle is level when on the jack stands.
Locate the drain plug on the bottom of the transmission pan and place a drain pan on the ground under the plug. Remove the drain plug with a socket wrench, allowing the transmission fluid to drain completely.
Remove the bolts on the transmission pan with a socket wrench and set the bolts in a safe place. Remove the transmission pan, using a screwdriver to carefully pry the pan off the transmission.
Clean out any debris and sediment from the inside of the transmission pan with clean paper towels. Unbolt the white plastic transmission filter from underneath the transmission with a socket wrench and dispose of the filter.
Remove any debris and oil from the bottom of the transmission where the filter attaches, with a clean cloth. Place the new filter gasket between the bottom of the transmission housing and the transmission filter and attach the new transmission filter to the bottom of the transmission.
Scrape the remaining gasket material off the bottom of the transmission and off the transmission pan with a putty knife. Place the new rubber transmission pan gasket around the lip of the transmission pan.
Attach the transmission pan to the bottom of the transmission and secure it with bolts. Screw the drain plug into the bottom of the transmission pan by hand until it is snug and tighten the drain plug with a socket wrench just enough so it is secure.
Unscrew the fill plug on the side of the transmission fluid oil pan with a socket wrench. Refill the transmission oil pan with transmission fluid, using a high output pump, until the fluid is running out of the pan.
Install the oil fill plug of the Audi automatic transmission pan and tighten by hand. Turn the engine on and place your foot on the brake pedal. Shift the transmission into each gear for about ten seconds to run the fluid through the transmission.
Put the transmission back into park and let the engine idle. Remove the oil fill plug on the side of the transmission pan by hand and fill the pan with fluid using the high output pump until the fluid runs out of the fill hole.
Place the drain plug into the side of the drain pan, securing it with the socket wrench. Shut off the vehicle engine.
Lift the vehicle up with a floor jack to remove all the jack stands and set the vehicle back down on the ground. Dispose of the drained transmission fluid at the local recyclers or automotive centre.
To avoid burn injuries, never attempt to replace the transmission filter on the Audi A4 while the engine is still hot.