looking for a Trans Doctor..


New Member
Nov 9, 2001
A friend of mine has been having transmission problems. Listed below is a quick synopsis of the problems we’ve incurred. Also listed are the series of corrections we tried to make to rectify his problem and, the additional problems incurred.

1st transmission.

1) Slips out of first. (While in drive and under light acceleration, pops into neutral. This is also when the transmission is warm.)
2) Erratic 2nd gear application. (When it wouldn’t shift out of gear into neutral, second gear would apply either late or early.)
3) Starts off in second gear. (Trans would rev and move slowly. This is while the selector is in drive.)
4) Converter switch would activate the lock-up feature while in first gear.
Because we had multiple problems with his trans, we conducted a psi check. Pressure in all selected gears passed spec in accordance with the Buick Manual. Although I must add, this trans has a modified P.R valve and I don’t have a clue what those specs are supposed to be.

CURE…..Donor Transmission.
Ok, I had a transmission I pulled out of my car a while ago. It was in good operating condition, and the only reason I pulled it out was to install a better one. So this was my reason of thinking. Swap the valve body to see if the old V.B. was the culprit. I couldn’t think what could be the cause of multiple application problems, and I wanted to isolate the two to narrow down the area of diagnosis. So we made the swap and still had the same problems. Well at that point, I decided to put the V.B. back in the good trans, and swap the transmissions out. Now we install this donor trans and it appears we don’t have 1st gear. It shifts good, meaning 2nd through 4th. We even have the lock up operating normally now. It just doesn’t want to give us 1st gear. Now looking at the hydraulic schematics, it appears that only the servo applies 2nd gear. If this is true, what should I look for in a psi test? Should I do a visual inspection of the servo and see if it is hanging? Because we swapped the valve body earlier could we have screwed up there? I mean in regards to check balls and there location. (I looked at the schematics and check ball 8 is the only one in the 2nd gear application and per the shift kit instructions, it was deleted.) I’m probably answering my own questions here but, I’m checking to see if my train of thought is in the right order. We’re running this hydraulic fluid from mobile instead of actual transmission fluid. It’s supposed to have better thermo characteristics than regular trans fluid. Could this be a problem, or a potential problem? Any professional comments would be greatly appreciated. Thanks in advance.