dachew57

I searched around and couldn't find anything specific to my issue - W203 transmission slipping.

Well, I took the car in a few days ago to have a minor oil leak investigated. They said the bottom transmission oil pan gasket was leaking, and since they had fixed it last year, they would fix for me. Also, I asked them to change the engine oil. While doing the work, they told me that the anti freeze had a Ph of 7.5 and should be flushed. I agreed, so they did the 3 things: change oil, fix transmission gasket, flush cooling system.

All was fine when I picked up the car - it drove like a champ for about 2 blocks. Problem started after I let the car coast to slow down for traffic. When I pressed the gas pedal to go again, the engine just rev'd and the car continued to slow down. At first I thought I had knocked it out of gear, but it was still in drive. It took a few minutes of going between reverse, neutral and drive before I felt the car move again: and I had to rev the engine up to about 4k rpms before the car would pick up any speed. Once it got moving, it seemed that the transmission and engine were locked - no graceful slowdown or acceleration, instant lurching when applying or releasing the gas pedal. Of course I took it back to the shop. On the way, I noticed the lurching would happen while the car was moving, but if I stopped for a light, then it would rev and slowly pick up speed - once at about 20mph or more, it would start lurching again.

On their test drive the car started smoking very badly. Lots of white smoke. It did not smell sweet or tangy like burning anti freeze, and it wasn't blue like engine oil, or black like over-fueling. Just white, and somewhat pungent. I've never smelled ATF fluid burning, but maybe that was it?

The shop says I need a new transmission and they have NO idea why it was smoking. On a final note, the transmission had never slipped before. It's hard to imagine that the transmission can wear out in a single afternoon. I'm suspicious that the shop did not use the MB ATF fluid, and that they are trying to let me bear the repair costs.

This is for a 2002 MB C320, with about 72,000 miles on it. I bought it used with 62,000 miles.

Does anybody have any idea why this is happening now, and why all of a sudden it goes from running and driving like a new car to needing a new transmission?

samaritrey

our transmissions are very sensitive to transmission oil levels they could have screwed that up. I would go and yell they must have done something if it was perfect before. also what type of shop is this?

another thing they could have done if they are idiots is put the atf fluid in the engine oil it has been done before.

dachew57

It's a generic European & Japanese auto shop. They usually do good work, and have excellent reviews on Yelp and Google.

I talked with an MB mechanic at another auto European auto shop and he said there's a very specific type of MB ATF fluid you have to use. I have a feeling they put a generic ATF fluid in. Is there a chance that the different, non-MB ATF could ruin the tranny? Is there a simpler repair, like a complete flush of all the fluid?

Also, there is 500ppm of ethyl-glycol in the new ATF - I wonder if my car has the killer radiator problem?

Glyn M Ruck

There is little doubt that your car has the dreaded Valeo radiator problem & the transmission is probably kaput!.

https://mbworld.org/forums/c-class-w...s-part-go.html

The wrong (usually GM) fluid will cause slow multi wetplate clutch lockup in the transmission & ultimately burn the plates. The kind of slippage you are talking about can only come from lack of fluid - either because the level is low or because the filter is blocked & the valve body is messing around due to lack of pressure.

Not good news - I know - sorry! Flushing the cooling system probably opened the flood gates into the transmission cooler. 500ppm is bad news in new fluid.