Begin with confirming that the modulator holds vacuum and is adjusted to correct pressure. I found modulator pressure online by Googling "Mercedes 722". You want to know what trans you have. The number is stamped on the passenger side directly above the pan gasket. 722.xxx.

There are specs in the FSM regarding the VCV. You begin with getting full vacuum to the line going to the VCV. I think there is supposed to be an orifice in the line that reduces the vac.

VCV vacuum is adjusted to between 8 & 12" at idle. Vacuum is supposed to drop to near 0" when the pedal is dropped. Again, there is a measurement that is difficult to describe. I made a gauge by drilling a 1/8 in hole as close to the center of a nickle that I could.

Hard shifts frequently indicate too little vacuum. The only way to get things right is to go through the process starting with the modulator.

I "think" i ended up with 42 on the green modulator for a 722.303 and 12" of vacuum at the VCV.

Transtec has a pdf manual and Mitchell has another that I found online.

__________________
85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.