220D Automatic Transmission Fluid Leak
 

Bought a nice 1970 220D about a year ago with 4 speed automatic transmission and 170,000 miles. Been driving daily for a year with no problems. Recently had a shift control rod end replaced by a shop specializing in older Mercedes and after that I had a transmission fluid leak begin. Took it back to the shop and they checked for leaks and said they could not find any obvious leaks areas and said that "these transmissions are known to have leaks when they get older". They offered to rebuild my tranny. This transmission according to previous records had a tranmsission rebuild in 1986 which I estimate to have less than 70,000 miles on it. Leak is now about 1 quart every 2 weeks and is coming out of the vent below the fluid coupling. Everything works fine as long as I keep fuid level at appropriate level.

My question is if there is an obvious place to look for leak? Does this sound like a common leak for these transmissions? Any recommendations for next steps?

(Only one other post from me....great advice given on converting leaky rear self leveling hydraulic suspension to shocks and springs...thanks for the advice...car rides great)

Thanks,

Bill
1970 220D
1983 240D

Bill:

Check the cooler lines where they go though clamps on the engine oil pan. when the rubber liner goes, the steel line rubs on the clamp and will eventually perforate where it contacts. It will ONLY leak on acceleration, leaves no puddle and no trail, but will run you out of trany juice.

Mine did exactly that, the only clue as a drop of tranny fluid on the oil pan lower edge. Ran out freely if I lifted the line.

The line is no longer available, so you will have to braze the hole up.

Other than that, the only place they leak is at the front seal (fluid dripping off the bell housing) or servo covers (fluid on the tranny pan edge). Stay away from any shop that tells you you need a tranny rebuild for a leak! That tranny, cranky as it is, should go at least 250,000 miles with nothing more than fluid changes and a band adjustment.

Peter

Thanks for your advice. I'll take a look at those areas.

Bill
1970 220D 170,000
1983 240D 200,000+