SL Transmission slip, help! - PeachParts Mercedes-Benz Forum

spinedoc · #1 03-31-2006, 11:56 AM

96 SL500 with 97k on it, runs perfectly until earlier this week.

Symptoms are very rough downshifting. Upshifting seems to be perfectly OK, downshifting if braking to a stop seems to be ok. No chatter or vibration, runs smooth.

If I accelerate about half throttle or more and it downshifts then I get about a second pause, with rising RPM's like its slipping, then it will slam into gear, rear tires will spin a bit, etc.

I am hoping its a valve body or something electrical, would hate to have the tranny go. I did do a transmission filter and fluid at 60k at the dealer.

Anyone have any idea?

iwrock · #2 03-31-2006, 03:54 PM

I think that it is a problem with the computer. I saw this on this forum, or another forum, and someone said the problem was fluid seeping into the trannie controller, and shorting it out.

jjrodger · #3 04-03-2006, 03:37 AM

I had very similar symptoms which were cured with a new MAF.

LeaUK · #4 04-03-2006, 05:25 PM

How can a MAF clear tranny issues? Confused

Any thoughts?

jjrodger · #5 04-04-2006, 03:14 AM

Quote:

Originally Posted by LeaUK

How can a MAF clear tranny issues?

That's what I said. When I took my car to the dealer, I was concerned my transmission was on the way out. They told me that when the MAF is bad, it upsets the fueling of the engine and the timing of gearshifts, which makes sense, because the ECU has dud info. On acceleration, the engine is under-powered: the revs rise, but there is no acceleration, it felt like transmission slip; and the gear changes were really clunky.

LeaUK · #6 04-08-2006, 02:52 AM

Interesting, seems to make some sense I suppose. I'll bear it in mind.

Cheers JJ

rellik · #7 04-08-2006, 09:55 AM

i have a 93 with the older hydraulic tranny and noticed that my fluid level was too high so i sucked out a bit and it fixed up the prob, before that i had shift delays and very hard shifts

i think the 96 has the new electronic tranny but i dont know if that could be the same issue...

tranny fluid level is an easy thing to check anyways

spinedoc · #8 04-17-2006, 08:27 AM

Any of those problems bring up a code? I would assume a MAF problem would bring up an engine code, which I do not. Although I have a PO410 code that pops up regularly, I forget what it is for specifically but I recall it being related to the AF somehow.

My indie tranny shop said there is no vavle modulator on my trans and it needs an entire trans. He is great usually and was the only one who saved me a trans on my old 92 SL that everyone else said needed a trans.

Just trying to narrow stuff down before I bite the bullet. He has a trans and converter for less than 3k with 2 year warranty.

LeaUK · #9 04-17-2006, 12:46 PM

Quote:

He has a trans and converter for less than 3k with 2 year warranty.

I appreciate you know him and trust him well, but that sentence rings a couple of alarm bells!

LeaUK · #10 04-17-2006, 01:10 PM

spinedoc

I have three or so documents that may help you/your mechanic. PM me your email and I'll send them.

I'm assuming your '96 is a 129.067 chassis on a 119.982 engine but I don't know which transmission you have.

My docs are for transmissions 722.3 and 722.5 which I suspect both relate to your car. I've searched for downshift issues and found 'Hard downshift 4-3 at approx. 60-70 km/h' corrective action is to 'Remove/install/replace brake band B2.'

Maybe of some use?
Lea

Carlos Serrano · #11 04-17-2006, 04:31 PM

PO410. That is the secondary air injection system malfunction

spinedoc · #12 04-17-2006, 06:05 PM

Quote:

Originally Posted by LeaUK

I appreciate you know him and trust him well, but that sentence rings a couple of alarm bells!

Adsit (which was recommended on this forum) has a rebuilt trans and converter for $2700 with a 2 year warranty. Im not sure what company he uses but his also has a 2 year warranty.