cgranger5000

I have a 1984 928 automatic and the tranny has started slipping. It shifts, once it has warmed up, but it seems real sluggish. When the car is cold, the transmission seems to lurch. Once it has warmed up, it shifts fine but tends to have a minor vibration. I am wondering, is this simply some type of easy maitience item I am missing ? Only owned the car for a couple months, or is this a major problem ? Thanks !

928 Is My Favorite Time of Day

Hi,

Sorry for your transmission woes. Do a search for transmission slipping, checking fluid level, modulator, transmission service. See if any of the previous threads give you clues to the problem and let us know how you make out. Good luck.

Joe

morganabowen

My first 928 was a 1982, which I purchased for $3K. It ran great, but after I had it for about 4 months, it began to exhibit the same symptoms that you describe in your posting Someone recommended a transmission shop which specialized in MBZ and Porsche. I took my car to them and after they test drove it, they said that I needed a rebuild and the cost was somewhere around $3K I then took it to a place in Ventura where another 928 enthusiast suggested that we drain the tranny, and replace the gasket and put fresh fluid It took a couple of hours, and when he was finished, the car ran perfect and I had the car for another three years without any problems

So, I suggest that you check with your mechanic and discuss the possibility of draining the tranny and putting fresh fluids and hopefully that will resolve your issues

JHowell37

It's funny how places will say they specialize in automatic transmissions and yet the only thing they seem capable of doing is transmission replacement.

CAShark

Forget the mechanic, it's easy to drain and fill the tranny. Plus you'll get the satisfaction that it was done right and you can also take a brush and clean all the grime under there while your at it. No mechanic will do that for you.

Landseer

First, don't panic.

The 84 transmission is supposed to be internally nearly identical to the Mercedes 722.3 unit.

They are highly documented on the internet and parts, including upgrade parts, are very available.

I don't know the answer to your symptoms, and hopefully some of our resident transmission experts will post, but do some extensive searching on the net.

To search here, put your keyword(s) in quotations. Otherwise, the search will return too many improper results.

A lot of the fixes seem relatively straightforward, so it shouldn't cost a fortune.


As a worst case reference, my dad just had a badly leaking 722.3 in a Mercedes removed, completely rebuilt, and reinstalled for $2000. Its expensive in today's times, but its not really much more than a quote on an american car these days. You may have a really simple problem/solution, like low fluid or bad vac connection, or a medium-complexity problem, but don't panic, the core is strong.

The rebuild of a 928 torque convertor on the east coast costs only $170 plus shipping, about $200 total. The shop I found for this will ship same day, with a core charge, or rebuild yours.

jpitman2

If an oil change doesnt help, visit the forums at mercedesshop.com, and tell them 722.3 , you will find lots of help there on our auto boxes.
jp 83 Euro S AT 52k

SeanR

Best bet is the B2 valve. If so, it is an easy fix, but make sure that the fluid/filter is new and levels are good.

cgranger5000

All of the info provided is very helpful ! It gives me a great starting point, I have a mechanic that can hopefully handle this ! Thanks for all of the great feedback