Hi everyone, happy to be a part of this great forum! I have paid specific attention to the shifting characteristics of my baby so I can give you an accurate description of my problems:

1) The "thudding" "clunking" downshift to first gear the I experience when coming to a stop. Funny thing is I can "baby" this sometimes and it won't do it, I have to come to a stop VERY SLOWLY. But 99% of the time I start to come to a stop and "THUD" into first gear.

2) TAKING OFF....1st. to 2nd.: Well defined, slightly harsh shift (unless I stay halfway into the accelerator, then its well defined, hardly noticeable) 2nd. to 3rd.: (same as above) 3rd. to 4th.: Slightly harsh, and not nearly as well defined as the others (regardless of accelerator position).

3) KICK DOWN.....I was told to test my kickdown switch for its proper operation (thinking it may be the culprit, I REALLY HATE DOING THIS, and I NEVER DO), so moving about 40, I engaged the kickdown, it DOES downshift, well defined, pretty harshly, I held it for a few seconds and released, the upshift was about the same, well defined, fairly harsh.

Now, I have already replaced the modulator, and adjusted, however I got sloppy shifts, and even the feeling of slipage when going too far, so I backed off things are the same, however, the mod. did correct an EXTREMELY harsh shift that used to take place when traveling at parking lot speeds. I have order the "flappers"/"levers" that are fitted to the top of the engine block as they are SHOT! I hope this helps....I am about 99% sure this is a vacuum issue, because my family used to own an '83 300SD and these symptoms (especially the "thud" into first on stops) began to happen, and were remedied by correcting it. However, that was over 10 years ago, and I don't know where to start here. ANY HELP/INSIGHT is really appreciated, thanks David.