300tdt - Vacuum Source Clarification

[Pato]

steve,

you wrote this to me the other day...

The 85 model is totally different from all the previous 123 diesels. It uses the vacuum amplifier. For the downshift harshness you describe you are losing the vacuum to the modulator. For this to happen with this system you must have a problem with source vacuum. The AC vacuum was usually the green line. Disconnect it from its source and plug it.

can you please clarify "source vaccuum" - do you mean the pump itself or the source vaccuum for the tranny...and would plugging the ac line help to diagnose the prob. I checked out the wikki link you gave me, and got some other info, about checking the brake booster line for oil (the brake booster may be making a funny sound, but i had this problem before the sound, i think...). its not that i dont want to take it to a mb mechanic, - i would just like to diagnose/replace as much as possible because i enjoy it and if i am going to spend $, i want to know why's and how's first.

thanks.
Glenn