Transmission on a 96 500S

[Ken Griffith]

New person to the forum, so I hope I'm asking the right kinds of questions.

I have a 96 S500 with 68K miles on it. I'm the third owner. The second owner had the Tranny replaced under warranty at 40K(yes that's right). I bought it with 60K on it.

Guess what? I am having transmission problems. I need to point the mechanics in the right direction.

When I am traveling at speed, then stop quickly(i.e. toll booth), the transmission hasn't downshifted, so I''m stuck. I have to manually put it in park, wait some time(20 seconds), then put it back in drive. Even then, it always doesn't get down to first and I have to take off in second.

Any ideas?

Secondly, when I am travelling around town at low speeds, periodically the car won't shift out of first. Again, I have to play around with the manual shifting until I can get it to behave.

Question 1. What might be wrong.
Question 2. Can I still get some help under the warranty(original was 4 years 50K, so I am outside that).

[David C Klasse]

First things first... have you checked the fluid level!?

[blackmercedes]

1. Is the check engine light on?

2. Get thee to a dealer and find if there are any codes showing. Veddy helpful.

3. Check the fluid level. When was the last time the tranny was serviced? Time destroys stuff, not just miles.

Is it a four speed or five speed?

[Ken Griffith]

5 speed transmission(1 - 4/D(left right toggle).

I can't check the fluid level S-500's don't have transmission dip sticks(at least that's what the manual says, and I could't find one)
but I'm willing to be told different.

I had a 60K service done at a Mercedes Service Center, and they were supposed to have replaced the filter and fluid, but I didn't actually see them do it.

Engine check light is not on.

Problems are intermittent but seem to be happening more often.

Probably a good idea to see if any codes show up on the computer. They can check transmission faults?

KG

[blackmercedes]

722.6 five speed tranny has no dipstick. It also requires a very specific synthetic tranny fluid.

Take the car back to the original dealer, and ask them to pull codes. You'll probably need to contact the Zone Rep if the tranny repair was done more than one year ago if you want MB to cover the repair.

It sounds like the tranny is occasionally slipping into limp-home mode. When it does this, it will sometimes lock itself into top gear. Makes driving un-fun. Limp-home will lock into gear, and sometimes low or top. Sounds just like your problem...

I've seen this intermittent problem before, and on one occasion it was a faulty tranny temp sensor that caused the tranny to go into limp-home. It believed it was overheating. For some reason it wasn't storing codes.

The problem was that the dealership kept disconnecting the sensor, replacing the tranny, and then reinstalling the sensor. (This was the story, anyway)

In other cases, the 722.6 has required some new parts. In JCE's case, they had to rebuild the tranny. A friend of mine, who's car is under warranty, didn't get to find out what was wrong, as MB just swapped the tranny out.

My local service manager has dealt with a couple of these problems. I'll call and ask if he has any ideas...