722.6 Shift from 2nd to neutral

[Roncallo]

I have read various posts and saw a few recommendations on similar situations. I have a 1996 SL600 which was received as a wreck. I do not know how well the transmission performed prior to or right after the wreck. But after servicing this trans and reinstalling it it now shift's from second to neutral, when trying to shift to third. Stays in neutral until you slow down long enough to get it to down shift.

In accordance with previous posts.
Checked and adjusted fluid level.
When the trans was out of the car there was evidence of oil wicking into the connector that was cleaned and a new material (white, old one was red) seal was installed.

Examination of the power flow for this transmission indicates to me that the K2 clutch is not engaging. Using Carsoft 7.4 software I get no EGS codes.

Considering each time I pull the pan on this it's $100.00+ I would like to get your thoughts. Should I pull transmission and do a complete overhaul or maybe pull valve body and replace 2-3 shift solenoid. Can I do a pressure check of the K2 clutches with the VB removed.

I am very familiar with overhaul of automatic transmissions in American cars only. But I've yet to do an MB. I can think of three sources of manuals for overhauling transmissions. Does anyone have anything more appropriate.

MB 129 service CD
ATSG Transmission manuals
All Data

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