Hello there,

Well, I just wrote a book and it was deleted before it was posted. Let's try again.

I just purchased a 1999 ML430 Mercedes with 108,000 miles from it's second owner 3 weeks ago. About a week ago, I started hearing a "clicking" sound coming from the front end, but was thinking that this was the front brakes, as they need replacing (And it might be). I had no tranny problems on the car except an occassional hesitation in shifting out of second on a couple of cold mornings.

A couple of days ago, when backing up from a level parking place, the car started "hopping" in reverse. I put the car into park, then in drive, and we took off with no problem. After less than a mile, the car slipped out of drive completely. I pulled over, turned the car off, and then back on. The vehicle engaged, and shifted fine out of 1,2, 3, and 4th gear. After a few miles, I pulled into a gas station to research what the problem was online. I found out that these cars are not designed to be serviced at all by an individual, and that there a "Lock" on the tranny oil filler. Upon inspection, I noticed that the locked cap had the lock broken. When I started the car and put it into drive, it would not engage, and just made a "rattling/clacking" sound. I left it, and the next morning it was towed to a local "Mercedes Specialist". After 2 hours with the car, he concluded exactly what a 16 year old at the gas station did "It must be the transmission". He said there were no codes for the tranny, and that he would be happy to fix it for $4000.00. Well, after paying again to have it delivered to another shop, they thought that it might be the torque converter. Well, this seems to not be the case, as yesterday I recieved a call that it was not the torque converter, even though they could not tell me what it was.

I would REALLY appreciate it if you guys can help me out. I have a few questions:

1. What do you think the problem might be?
2. What is the transmission code for the 1999 ML430 Mercedes (722 6??)?
3. Will a 2000 s430 transmission work in this vehicle in any form or fashion?
4. Where can I find the best deal on a used tranny for the best price if this is the problem?

I just think that it is strange that a tranny that has shifted as smooth as silk would just die with no prior warning or problems. Any input is GREATLY appreciated!

 

Hi,
Not a good start with your MB.

Yes MB apply anti tamper devices to the trans filler and also do not fit a dipstick to the trans.
The logic behind this is that the trans is considered to be a "sealed for life" device and MB consider that the risk of overfilling is significant and the risk of requiring attention very low.

MB garages will replace the anti tamper seal if indeed they happen to check the level for whatever reason. Independents etc do not usually bother with replacing this device. Its only purpose is to discourage access and to leave a "witness" that the oil / oil level has been potentially altered.

Yes it looks as though the transmission has failed. However the transmission ectends further than just the gearbox. i.e. driveshafts (X4)

You do not state whether the oil level is infact correct. I will assume that it is.

The hopping is significant and I suspect that the failure that has occurred is possibly due to continuing to drive without investigation this "issue". I know what you mean but at this very early hour I can't quite recall a reason for such an incident other than the front and rear trans are winding up and then suddenly for some reason releasing. Sounds like the front / rear diff has failed.

IF the car is with an MB dealer I find it difficult that thety cannot diagnose this issue. The hopping is significant!
It may be true that there are no codes since this is potentially a catastrophic failure of some heavy duty component within the box/diff rather than a performance / electronics issue although I'm still surprised that the electronics didn't notice something amiss with the hopping.. The real question is why / how such a component could fail.

I'm afraid I can't offer much more assistance from a distance.

JFYI the ML is made in the USA rather than Germany. Not sure where the transmission is made however.

I don't believe a trans from a S class (w140 or w220?) will fit. Most S Class are only 2 wheel drive. Only a few are 4matic.

Stuart