Thanks Mike. Well, I did know it was hydraulic with vacuum assist, LOL......I should have written my last post a little differently......LOL...

Anyway, this is just the kind of information I wanted to know. Once I shut the engine off it seems the tank emptys immediately. Otherwise, under normal driving conditions, the brakes work well. I was thinking of installing the tee behind the tank going to the brakes this way I can monitor actual vacuum to the brakes. Any thoughts?? I don't know if any of this makes any difference.....

Oh, what should the vacuum be, 18" ?????