4matic transfer case leak
 

My 91 4matic with 135k started leaking at what appears to be the rear of the case. Big oil leak observed after driving on slick roads and engaging the 4 wheel drive. I have just spots on the floor after driving without engaging the 4matic. Is there a solution short of replacing the transfer case? I assume the engagment system is leaking into the case and overfilling and leaking out a seal.

My '91 had the transfer case seals replaced at about 70,000miles and again at 125,000 miles. If it were the hydraulic fluid it would be running low quickly (PS reservoir), it is probably the transfer-case fluid.

- Jeff Miller

transfer case
 

What kind of fluid is in the transfer case? My hydraulic level is down some. The fluid on the floor was brownish verus red color of AT fluid. What kind of cost for the seal replacements? Thanks for the input.

additional tranfer case
 

I answered part of the question that the transfer case uses ATF. If the hydraulic system is leaking where does the hydraulic fluid go? How is the transfer case filled? Is it filled with the AT or is it separate?

Transfer case repair
 

Has anyone found a way to repair a 4 matic transfer case. It is my understanding that MB will not sell repair parts, but only a complete transfer case. I have narrowed down the problem to internal hydraulic fluid leaking into the case and therefore overfilling and contaminating the AT fluid. If I disenable the 4matic with the test lever and change the AT fluid in the TC will I be OK to drive the car? I have heard of one story of an owner blowing up the TC on the road. I assume the cause could have been the same issue.