When your Audi A4's transmission fluid is clean, it will appear clear and thin. However, thick and dirty transmission fluid can build up on the inside of your transmission, causing multiple problems that could result in costly repairs down the road. For this reason, your Audi's transmission fluid should be changed between every 30,000 to 60,000 miles, depending on the driving conditions of the roads and areas to which your vehicle is most often subjected. If you are mechanically inclined, changing the transmission fluid is a task you can most likely tackle without the assistance of a professional mechanic.
Warm your car's fluids by driving at least 10 minutes before parking. This allows the fluid to thin, making the emptying process easier.
Elevate your vehicle evenly using a car jack and jack stands.The car should not be tipped in either direction, since a tipped transmission is dangerous during the procedure because hot fluid could spill out and cause injury.
Locate your transmission pan under the driver's side hood of your vehicle. The fluid will be in the square, bolted filter pan.
Place your dripping pan on the ground beneath the transmission pan area, as a safeguard in the case of spillage.
Remove all of the bolts using your socket wrench on one side of the transmission pan, beginning in any corner. It is important to take the bolts off very slowly, so that any fluid that drips will gradually fall into the dripping pan and not on you.
Lower the transmission pan to ground level without tipping it to either side, since it is likely to be filled with old transmission fluid. If any fluid spills, use your shop rag to wipe up the spill.
Discard the old transmission fluid by carefully pouring one corner of the transmission pan at the opening of the milk jug until the pan is completely emptied.
Wipe the transmission pan clean, so that no particles or residue from the old fluid can contaminate the new fluid.
Mount the transmission pan back into its original position by hand-tightening the bolts for a temporary hold.
Secure the bolts into place using your socket wrench. It is important to wiggle the pan a bit to be sure that no bolts are loose and that there is no crevice between the transmission pan and the actual transmission.
Remove your jack stands and lower the car jack with caution.
Fill the new transmission fluid to the "fill" line. The typical refill capacity for an Audi A4 is three quarts, although you should watch the line carefully to be sure that you do not go significantly over or under this marking.
Run your engine in the "park" gear for approximately five minutes before checking the fluid levels again. The warmth of the engine will make the fluid settle into the transmission.
Measure the fluid level using the transmission dipstick. If the fluid reads below the capacity line, more fluid can be poured into the transmission opening while the car is still running. Shifting the gears of the car may also help the fluid to settle for a more accurate reading, although this is not required.
When the dipstick shows the transmission fluid at a sufficient level, the transmission fluid change is complete.