722.6 Awkward Downshifts
 

Help! I recently aquired a 1998 E320 4-matic wagon with a transmission problem. The car has 70K miles and when downshifting to an incomplete stop it hesitates and/or clunks hard into second gear. The previous owner recently had a $500 "on vehicle repair" by an independent shop that reportedly made the problem less acute. What do you guys think is causing this? I am a pretty good mechanic, but clueless about these electronic transmissions. By the way, is the 722.6 similar to the ZF model 5HP24?

David R.

722.6 are mercedes benz made in house, some of the manual shifts done with the gear shift are electronic as opposed to mechanical linkage - which is kind of cool.

Supposedly (something I had read in a car magazine) five speed automatics have an inherent hard downshift when slowing into a low gear.

That drivability problem was valve body related in the early valve body, pre 2000/ 722.6 transmissions. I am not sure if MB can check the VIN for any updates that were done to that car. If it’s an early VB, You need an update one and soft ware flash to the TCM. Resetting the additives may cure some of the harshness, but then you have to do a 1 hour adaptation drive cycle. ZF are weak transmissions, they can’t handle hi torque loads.