Sounds like you're confusing this really tough transmission for a GM model. Chrysler never used a trouble-prone vacuum modulator valve for shifting. That is done with a very simple, reliable linkage from the throttle body. The sensor at the rear of the transmission is the vehicle speed sensor (VSS). If you have rear-wheel-anti-lock brakes, the speed sensor for that is in the top of the rear axle. The lockup torque converter was invented by Chrysler and first used in 1977. It was completely hydraulically-controlled. Yours will be electrically-controlled by the Engine Computer. Unless there is something I'm not aware of, you should have an overdrive unit added to the tail housing of the transmission and there should be a square button to the left of the steering column to turn it off. There should be a circle around the "D" on the shift indicator if I'm right. The filter can't fall off as in some other manufacturer's designs because it is held on with three screws.
If you look at the transmission pan and it is basically a rectangle with the right front corner shaved off, that is based on the old 904 model. It is being used more because it is lighter weight. Trucks and vans usually had the tough and reliable 727. The pan for that one has an extra "bump-out" on the right front corner. (The 904 pan is missing a part of the rectangle; the 727 has more than a full rectangle). Both models use the same valve body but the clutch packs are larger in the 727. Neither one is computer-controlled in '94.
When it is slipping as you described, the place to start would be with pressure tests performed by a mechanic. Those will help isolate the cause of the problem.
Wednesday, March 2nd, 2011 AT 3:10 PM