Visual inspection of automatic transmission for leaks (Mercedes-Benz S-Class W220)

Gearbox oil leaks may occur in the following places:

• The plane of the junction of the cylinder block and the AT (rear crankshaft oil seal).
• At the junction of the drive shaft to the gearbox.
• Near the oil drain plug.
• Near the oil filler cap.

To locate an oil leak, follow these steps:.

1. Clean the gearbox housing.

2. Cover possible leak areas with a thin layer of chalk or talc.

3. Take a test drive of about 30 kilometers.

4. Raise the car on a lift or over an inspection pit and determine the location of the oil leak based on the oil leaks.

5. Fix the leak and fill the gearbox with oil.

The oil in the automatic transmission does not need to be changed during the entire service life.