The infamous B2 servo piston

First of all I would like to wish Happy Holidays to all. Here is my problem: 1983 300D turbo , 722.314 trannsmission ,154,000 miles. I had the classic B2 failure symptoms of no forward movement under
load,if I let it creep forward on it`s own it would catch and was still driveable as long as I didn`t park facing uphill. As a matter of fact the transmission shifts fine once I got going,no flaring , harsh shifts or leaks. I dropped the transmission down far enough to get at the B2 cover and when I removed it the servo piston came out in pieces. I purchased the latest version of the piston along with the new plastic bushing as well as a new bushing seal. Getting the old bushing out was not fun in that cramped space but I did manage it. The brake band end where the rod fits has movement and there is resistance when pushed in so I don`t think the band is broken. Piston bore was not damaged by the broken servo so I thought "No problem , put new B2 in and drive it." Wrong!! After installation I put it in gear and it worked to get me on the way down the street where I backed into a driveway to turn around. When I shifted from reverse back to D the engine just reved up and I lost all forward movement. So I towed it back to the barn and opened it back up to make sure the thrust rod was correctly positioned in both the brake band and the end of the piston. All looks good but still no forward movement. Reverse works fine. Any input would be greatly appreciated. Thanks in advance, Stephen Doerr
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Einyodeler wrote:

I forgot to add that according to the maintenance records,the car has been very well maintained ,all fluids changed regularly. I have all records since the P O bought new including the original window price sticker. Very clean looking transmission fluid when I drained it, no particles in the pan and no burnt smell to the fluid. The PO never even drove it in the winter,this car has no rust whatsoever on it. Which is pretty amazing for a 23 year old car from Kansas.
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http://articles.mbz.org/transmission/b2/repair /
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Take A Guess wrote:

Hi, I read through the article and have already changed out the servo with the new style piston but now there is no forward movement whatsoever. Thanks,Stephen
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