Originally Posted by herring

Ok, I bought some vacuum line, some Y-adapters and a Mityvac. First, I attached the Mityvac and drove around. 11 inches of vacuum at idle, down to zero at full throttle. I thought that was odd, that's pretty much in-spec, and the way the trans drives is definitely not.

I had called the dealer for orifices and they told me they are all unavailable except for the largest (yellow, 2mm) and the smallest (green, 0.8mm). I bought one of each. (Kudos to Larry at Mercedes Benz of Fort Washington, PA for his patience with me and also for mailing me the orifices when they came in.)

After pulling things apart, I noticed that my car DID already have a yellow orifice installed. So, I replaced it with the green one.

Shazam! Shift points are where they should be, shifting is smooth. I can't believe it, and all with a $4 part. It's like a whole new car. Thanks for everyone's help, even though this turned out to be simple I'd never have been able to tackle it (or even know the part number for the green orifice) without your help!