I will not be the bearer of bad news...just yet.
Try adding 6 oz. of this product to your transmission fluid:
(Their web page reads like an ad written by P.T. Barnum...BUT the product works)
http://www.auto-rx.com/auto-rxnet/index.html
'Drive the automobile for 500 miles.
(Ignore their directions about how to drain the transmission...You have a
torque Converter Drain plug.)
Drain the transmission fluid(Don't forget the torque converter) and
replace the Tranny Filter.Refill the transmission with a Good Synthetic ATF
(Redline,Amsoil,Royal Purple,Etc.)
What you're trying to do is gently clean out all the funk in the tranny and
maybe soften some of the seals...To attempt to lengthen the lifespan.
This is for your future Tranny service plans:
85 Mercedes 300D Automatic Transmission Lifespan...
Oh, You will read up on how to check your timing chain "Stretch" (wear)!
[Click on "Search" then "Advanced Search"]
There is a list as long as the road from NY to LA ,If it's been neglected.
If it's been cared for ...just continuing regular maintenance.