Transmission Virus
 

I apologize for this long note but I'll really appreciate your adise.
My '88, 420 SEL, 77K miles, has the dreaded reverse-gear-itis. Reverse has been slow to engage. I changed the ATF and filter and it worked much better, then a couple of days ago I thought I had lost it altogether. I rev the engine and nothing happens for several seconds then it engages and the car shutters as it backs. Previously, before the fluid change, the shift was delayed and if I was parked down hill, it would kick hard into reverse. (All forward gears shift smoothly.) I've searched this form and others. I hope for a miracle fix but the bottom line seems to be a trip to a dealer or transmission shop, and big bucks which I don't have. I read somewhere that the clutch pack can be replaced without removing the transmission. Is this true? I've also read that most dealers and many transmission shops will advise a replacement transmission. But I've also read that some shops will work on the transmssion without tearing it out. Can any one recommend a shop in Dallas, or preferably in northeast Texas (Longview, Tyler, Mt. Pleasant, Sulphuir Springs) that is trustworthy and "reasonable?"

Lakelover:

On another MB WEB site, I've heard more than one person say good things about the MB dealer in Tyler, Texas. I believe he is also an Oldsmobile dealer.

Using the SEARCH facility here, key in "reverse" in the search field and click on title only. Some posts indicated that repairs could be done with tranny in car. You won't know 'til a pro checks it out.

no reverse sel 420 fix it
 

The clutch pack that engages for reverse is the 'front' one in the transmission. In all probability, the lip seal around the input shaft has cracked, allowing the apply pressure to leak out.


Since this is the first one behind the pump, the tranny does not have to be completely disassembled.

I has this done to mine from a 89 560 SEL. The tranny work, including parts was only $150, and done by a shop that does all the MBZ and BMW trannys here in Houston (and authorized to put the factory Remanufactured stamp on them!


Replacement clutch disks and seals are inexpensive ($25).

The tranny removal/reinstallation labor will likely cost $300-$400

No need to rebuild the entire tranny.

Thanks for your encouraging replies and referral. Maybe my tranny problem won't cost me an arm and a leg after all. I'm crossing my fingers.

Transmission repair quotes
 

I've made a few tranny service contacts and they're not encouraging. Classic Olds/Mercedes in Tyler, Tx. quoted up to $3,000 for a replacement and $2,400 for pulling the tranny and analysis. I also checked with a couple of transmission specialists. One said it could run over $2,000. The best quote was $1,200 for replacing the clutch bands and/or replacing the modulator and $150 to $200, if a simple adjustments would fix the problem (whatever they do is warrented for 12 months or 12K). I am concerned about about turning the car over to a shop that is not a mercedes specialist but I may have to risk it to get a job that I can afford.

Hey Jerry, I just overhauled 2 identical transmissions just like yours. It costs about $200 for the parts and a lot of work to get it in and out of the car. Your description of the delay and shuddering in reverse is exactly how mine failed. The tranny shops want you to believe it is difficult and expensive. But in fact it is really very simple if you know the tricks. I would be very happy to help you if I can assist some how.

One of the options I investigated before I decided to rebuild my own was a MB rebuilt unit from the dealer. They can be had from MB for about $1700. Then whatever it takes to put it in. Two year warrenty.

Where are you located? I cannot find Lake Cypress Springs.

Good Mechanic in DFW area
 

The place I goto to get advice on my 300D is German European Imports here in Plano. All the mechanics there are certified MB mechanics and have been working on them for a really long time (on the wall they have one plaque from 1974). They're very honest and will explain what needs to be done, and if there are options they'll give you em.


You can reach them at (972) 422-7780. The head mechanic's name is Sam, if you want to talk with him. They are located at Ave K and Plano Parkway (1100 Summit #106 is the address on their Business card)


As far as replacing the Transmission, for my car. The Tranny costs $1800 for a rebuilt unit from the MB dealer (Ewing ********)

Dave . . . Lake Cypress Springs is between Mt Vernon and Winnsboro and two hours east of Dallas, off I30. It would be quite rewarding to do my own tranny rebuild, but I'd only feel confident if somebody who knew the "tricks" was close by. Too bad I'm a good day's drive away from Houston. I've been to a web site that gives a lot of overhaul detail and overhaul kits: www.transonline.com. It appears that the toughest part of an overhaul is pulling the transmission and replacing it. BTW, what all did you replace, fix, adjust in your tranny rebuild?

Capt. Kirk. . . I'll give the Plano outfit a call. Thanks for the referral. That's give me another qualified perspective to my problem and probable cost.

Jerry

I replaced all the friction parts except for B2, and the vacuum modulator, all seals , O rings etc. The B2 band almost never needs to be replaced. It is tuff as nails (so the experts say). I purchased a manual from ATSG and a I also used the info from transonline.com and a little advice from a rebuilder near houston. Only needed a 30mm deepwell socket to get the driveshaft nut off. No other special tools were needed. I did use an arbor press a couple of times. After I was done, I took it to Jaggi Import Export www.jie.com to have it dyno tested ($80). I wanted to be sure that I did it right before putting it back in the car. He said that is worked great, so I was a happy man. He adjusted the modulator pressure and did whatever other adjustments were necessary. He is a real nice guy.

Cost = parts $200, dyno $80, = total of about $300.

I have to say that the feeling of accomplishment is very rewarding and makes it all worth while to me. I had plenty of time and wanted to learn how the automatics work.

I have a freshly rebuilt one sitting here ready to go, wana make a deal?