Tranny shifting hard
 

Hi, I'm a newbie here, just purchased a 83 300D with 194,000 on the clock. The transmission is shifting hard. I've already done a search on this and found tons of great info. I had very little vacuum going to the tranny modulator wich I think was caused by a sticking check valve near the brake booster. Once that seemed to free up I now have good vacuum(15") going to the modulator but the moment I rev it just barely above idle the vacuum falls very fast to near 0". The modulator seems to hold vacuum well. I ordered new levers for the valve that is located on top of the valve cover(the bottom one is completley worn away). I also checked the green orifices and they were clear. Should I start looking at the vacuum control valve next? I looked at the test procedure for the vacuum control valve, but I wasn't exactly clear on how to do it. I think I"m on the right track, but I would greatly appreciate any advice. Thanks.

Fixed problem
 

I bypassed the valve on top of the valve cover and it shifts great now. This site is a goldmine of info on these cars!!!! Thanks

+1 on bypassing the crap ontop and then check the VCV. The VCV is the most likeliest culprit.