[silicon212]

Originally Posted by Blue Bowtie

You mean it shifts like a Ford MXO (soft a a baby's behind)? Is reverse working properly and engaging firmly?

A few WAG -

• The "E" clip/lock ring under the 4th apply piston in the 2-4 band servo is missing or damaged;
• The oil passage in the band apply pin is clogged;
• The 3rd gear accumulator is not dumping on shift to 4th (valvebody or separator plate problem?);
• Leak past 'O' ring on outer piston or at center of outer piston to pin
• Oil leak between inner end of piston and case (right near the band end);
• It's cursed.

That's all presuming that you have 4th apply pressure. I've seen a few covers that have been converted with a brazed-on 90° fitting to take a pressure check right at the servo (doesn't help for 2nd gear).

The E-clip was there and intact, the oil passage through the pin was clear, the accumulator I didn't check, there could be a leak on the O ring on outer piston, could be leaking on the inner end, and I think it's cursed.

When I pulled the servo cover off and pulled out the contents, I noticed the inside of the case, where the outer piston rides, was worn to the point that it had a ridge, like a worn cylinder on an engine. It has to be a high mileage transmission - I don't think there's any hope for it. My seal change on all 3 components of the servo tightened up the 1-2 a little bit, and I mean a little bit, but at least it didn't go the other way. The OD is still a mystery to that transmission, however. I am not so sure that it's slipping - it seems that when the 3-4 shift occurs, I get engine braking! The car slows down unless I really punch it (which downshifts it into 3rd or 2nd depending on speed).