85 380SL. Transmission seems to work fine except for engagement. There is a 4-5 second delay before the transmission catches when moving into D from P or N. There is a similiar delay, maybe a bit longer when shifting between R & D in either direction. Did a search, several others have asked a similiar question with no response. Is this normal? I recently purchased the car, will be dropping the pan to change the trans filter this weekend. Anything else I should be checking while I'm in there? On my prepurchase inspection the oil level was correct. The fluid was dirty, but not burnt. Could dirty fluid be the problem? I know about half the fluid resides in the torque converter. Is it possible to drain it? Anything external to the transmission that I should be checking. Thanks for the help.

This is definitely not normal.

There is a drain plug on the torque converter. You have to turn the engine such that the drain plug is at the very bottom. Only turn the engine clockwise as viewed from the front of the car. I don't miss the days of having to turn an M116/7 engine by hand.

I had similar symptoms on my 78 450SEL. Not long after the delay when shifting into R or D, I would get a delay even while idling in D. I'm at a light, transmission in D, when the light turns green, I have to rev for a few seconds before the tranny engages... and I never took it out of D. Then it would happen even when cruising. I don't know what specifically was wrong because it was simpler and only $800 to replace the transmission than to have it diagnosed and repaired.

I don't mean to scare you, but look out for the dangerous progression if your transmission has the same problems mine had.

Sixto
91 300SE

First thing is have the tranny completly flushed with a power flusher not just a fluid change. Call transmission service shops and ask where to get it done. Then change the filter.

If it has not significantly improved to satisfactory, have the operating pressures checked and adjusted. The previous owner might have had it adjusted to give very soft shifts (low oil pressure). This causes lots more clutch wear.

If operating pressures are OK, what you have left are worn clutch linings on the front clutch.

It only costs around $125 for a transmission rebuilder to rework just the front clutch, but removal/reinstall labor can add $500 to that.

I looked into having a non-MB power flushed recently as this vehicle has no drain plug in the pan and for a multitude of design reasons, is very difficult to do a fluid change on.

Valvoline fluid change center rep hands me a waiver to sign that absolves them from any liability. Power flushing has an unfortunate tendency to break things (dirt) loose. A speck of dirt can kill a tranny. I said thanks, but no thanks and went about the drudgery of doing it myself.

I don't know about your MB, but mine has a drain plug on both the pan and the converter. I can drain the entire system, at least I think I'm draining it all.

Stu Ritter of the Ritter-Easley list commented on your situation several months ago. According to Stu, a delay of about 2 or more seconds was indicative of a tired transmission.

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"