It "chugs" or takes a second to engage when putting in reverse.
No problems at all going forward.

Love my '91 560 SEL and do not want to have to change or replace it .
I brought it to a shop in Cape Coral Fl where I live and the owner said the tranny was "shot"

I asked him how much life was left in it and his reply was " 5 weeks or even 5 years

This is a known issue for w124's but I believe it applies for w126 as well. It's most likely the reverse clutch pack friction disc that are worn. Just search "reverse transmission" in the titles only and you will get a boat load of hits. Your mechanic is right about how long you can go before it goes belly up. It will get worse...your delay will go from 1 sec to 4-5 sec...then slipping in reverse when you gas it a little or reverse engaging on an incline with the back facing up the hill. Some experience out right reverse failure too with minimal syptoms too. You also may hear some clicking when you are in reverse at some point.

You'll get some advice to do a partial rebuild of just the B3 reverse friction disc (800-1200) or overhaul the whole thing (1500-2500). I just did the B3 disc and my tranny has never been better...mine was exhibiting much worse problems than yours but it took it about a 1 1/2 years when I noticed the delay in reverse.

on my 300SE transmission the reverse section disks were all worn out Surprisingly rest of the plates were in excellent condition . A seal kit and the relevant disks brought back transmission to perfect smooth operation

Ad

Ah, the 91 560 SEL. Best of the bread

I have the same issue. Going on a year and a half since I asked about it here. Its getting worse, but slowly. I use reverse everyday to get out of the garage.

But I have learned to always park on flat or reverse grades!!! More than 4 degrees nose down and I am screwed!

So save as much wear as you can for now and avoid reverse, especially avoid revving the engine. I found that if I put it in reverse and just sit for a couple seconds it will start to engage.

I wanted to fix this last summer but could not locate the right transmission.

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1991 560 SEL / 185k miles
1992 750il / 17k miles - project car

I had the same symptom in the 350SDL. The reverse discs were worn almost to the metal. $1700.00 later and she bangs gears every day! Not an expensive transmission to freshen up compaired to the computer controlled newer ones.

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1991 350 SDL, 2006 E320 CDI

I replaced my reverse soft plates and the front seals only, about 3-4 years ago, and all is still perfect at 220K. Everything else I checked looked brand new.
The issue with waiting is the potential for additional damage in the tranny, due to the soft plate material coming apart and clogging up the filter and/or small passages. If it's already to the audible clicking stage, then the clutch plate basket is shredding metal chips into the tranny - not a good thing.

There are arguments pro-con about doing just the B2 soft plates vs a total overhaul, sinch the RR cost is a major part of the expense. In my case, my tranny was working perfectly except for the reverse, and I was more comfortable with just going in and fixing that, since I did all the work myself. Really easy to get to the B2 plates, by the way, once the tranny is out and on the bench.

DG

I cannot thank you enough for your very valued input .It is already ,ocassionally ,gone to 4-5 seconds .
I am going to ask my mechanic if he can this work without having to go to the dealership
again many thanks !!
Donal

cannot thank you enough for your very valued input .It is already ,ocassionally ,gone to 4-5 seconds .
I am going to ask my mechanic if he can this work without having to go to the dealership
again many thanks !!
Donal

If you are to remove the transmission to replace the B3 friction disks, you MUST reseal the front pump, period. You do not want to remove the transmission again to replace $5 worth of seals. They all leak sooner or later and it makes a huge mess when they let go.

If the car has no issues going forward, just do the B3 bands and the front pump seals and leave it alone!! If your mechanic wants to do a full rebuild, decline or take it elsewhere. These transmissions are very tough other than reverse and leaks.

Also take the opportunity and visually check the kickdown solenoid for hairline cracks. Again, common issue eventually. There was an updated part later.

PS: Don't change the oil, or you'll almost certainly lose it completely. Get it rebuilt as soon as you can.

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k

How much additional work would it be to have the tech replace the rear main seal on an M119.975 while he's in there?

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

Thank you ever so much for the advise ..I will make sure I follow it
donal

Hey Donal,

If you still are researching the B3 friction disc replacement. Here's some other easy things to replace while you transmission is dropped. Some can be some while the transmission isn't dropped but it's a whole lot easier with it dropped.

1. Front Flex plate. Mine wasn't cracked but it was swollen. Had to take it off in the process so it didn't really added any time to put it the new one in. The rear one looked good to me (and I was getting tired) to replace it. (About 90 bucks with new bolts/nuts/washers)
2. Check plastic shifter knuckles...There are two with the clips...less than 5 bucks to replace parts wise. This is if your shifter knob rattles or feels sloppy.
3. Obvious but the transmission pan gasket and filter.

Like Ph2cho said earlier...the front pump seals is critical even if your transmission is not leaking. One of mine was 1/4 torn on the bottom lip when I had it apart. and the O-gasket on the pump was really stiff and felt like it was going to snap into two.

Emerydc8, I bought the rear main seal ($15-20) but when I checked mine out it wasn't leaking nor did the shaft output have any play or wiggle...didn't want to mess with it. But I figure another around $50 labor to replace it is about right from an indy shop if the tranny is already dropped..

Thanks. I guess it would be worth considering it at $50. Just curious, has anyone found the forward plates worn on a 722.3xx. I had well over 200,000 miles on my 400E and you could still see the Mercedes logo on the discs. I suspect that unless the car was raced, these forward clutches last virtually forever.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

My forward friction bands looked virtually un-worn when I checked them out. But I've got 120k mi on my wagon. When you have the front side of the tranmission out you can see why it made a clicking sound in reverse. I could actually see deep metal scratches on the back side of the front pump cover from the worn B3 friction bands allowing the forward clutch basket? extend out further...hitting the front pump cover...causing the clicking while in reverse. Make sense??? If anyone ever hears a clicking in reverse, know that metal shavings are in your transmission.