The trans is a 81 electric lockup th350. This trans was rebuilt at 70,000 miles and the old converter reused, at 75,000 it lost all gears even reverse instantly. I bought it at this point with a good running Buick 350 I have the papers from the rebuild sayinig it was fully rebuilt, and they reused the converter by customer request and against thier advice. I pulled the pan to find clean fluid and filter so I'm thinking the converter was at fault. Should I get the trans rebuilt again to be safe or try just a new converter?
If it lost everything all of a sudden, I'd check linkage first. If everything checks out on the outside, drop the pan and make sure The "S" link is still connected to the manual valve.
Well I guess it wasn't all of a sudden, within a few hours of driving it started slipping and then lost all the gears. The fluid level was fine and it had no leaks. The linkage was fine and the s-link is connected. I pulled it from the wagon in this state and haven't used it since.
The fist time I rebuilt a th400 the same thing happened to me. Ended up being the front pump. I did not use dowel pins to align the pump upon reassembly. If you take it out and disassemble it the surface on the sides the sungear comes in contact with should be smooth. If there is any gouging in the pump is likely the problem. If it looks fine reassemble the pump use dowel pins. The symtoms were after the rebuild it worked fine for a few miles of city driving then it was slipping more and more until it would barely get me home. At first I thought it was the switch pitch staying on 1400/4000 but it wasn't the problem. The front pump was cooked. When the front pump is gone no gear will work. Hope this helps. Ray
I'm just going to use a different trans because the converters are supposed to weak in the electronic lockup Th350-C. Thanks for the input.
