What a great explanation. What I have missed all along is the action between zero vac and full vac; ie the moderation of vac and its effect on shifting. That is something I did not experience when I was troubleshooting my new tranny.

Great explanation. And we were all somewhat right and somewhat wrong. Or as they say - a little knowledge is dangerous.

Where have you been all this time?

So have we helped the original poster any?