Join Date: May 1999
Location: SE Florida, USA
Feedback Score: 0 reviews
Vacuum isn't your problem. Even with no vacuum the trans will engage and operate, it will just shift at high RPM.
Dex/Merc isn't your problem, either. If the friction materials were designed for Type F instead of Dex/Merc the trans will operate normally except all of the shifts will be long and slippery.
Here are a few things that I can think of that will cause no engagement.
Low trans fluid
Loose/missing internal filter
Torque converter not seated on the pump
Bad/missing internal clutch seals
Linkage not connected to the manual valve
Former Automatic Transmission Engineer 1988-2007
“The good thing about science is that it's true whether or not you believe in it.” ― Neil deGrasse Tyson