1985 Cutlass Supreme Transmission Problems

[gofast123]

Advice welcomed!

I have an '85 Supreme with a 307 (no overdrive). The transmission acts up after driving it a while. It seems to go through 1st and 2nd gears fairly smoothly, but shifts into 3rd way too soon and then the engine bogs down. I'm taking it to a Transmission guy tomorrow and was just wondering what the possible issues could be.

Also, I've seen out here where some guys say certain transmissions "are junk" and they swap them out for better, more reliable transmissions. If this is true, what transmission do I have now, and what transmission, if any would be better if I wanted to spend the money?

Thanks for your time guys...

 

[KrisW]

With no overdrive, your trans is probably a TH200C. I think everyone agrees that this one is on borrowed time behind a V8. It sounds to me like your problems MAY be alleviated by replacing the TV cable and adjusting it PROPERLY. Failure to adjust it properly will burn up your trans prematurely, so research it and do it right, or have a trans shop do it.

My two cents about the swap? I say pay the money and get yourself a 2004R that has been upgraded for more horsepower. Be prepared to spend some real money for that one, but you won't be disappointed. The best aspect of this swap is that you don't have to change even one thing to put it in. Your lines and dipstick go right on, the wiring is the same for the lock up converter, same TV cable, same dimensions in length so same driveshaft. On your 85, you simply move your crossmember back to the next set of holes since the mount is further to the rear on the frame. Everything else is in the same spot.

I did this swap in my 80 Cutlass, and I couldn't be happier. I had to fab a piece for the crossmember on the driver's side, because the older G-bodies don't have both sets of mount points. The newer ones do, or you can get the 2004R crossmember from the wrecking yard. You can also buy the aftermarket G Force piece and have a double hump for dual exhaust.