I removed my tailshaft to install new speedo gears. When i drove the car i had no overdrive. The trans still shifts hard but when it comes to the 3rd to od shift it dont do anything (as in wont go in gear). I took the tailshaft off and somehow my speedometer driven gear got chewed up. Can droppping the pan and replacing the filter solve the no shift problem? What can cause a trans to loose overdrive?


Its a 700r4 with shiftkit. around 15000 miles since rebuilt. Im also running a trans cooler, so i doubt its fried. Im also running TCI max shift fluid. Any input is appreciated

 

Oh god i need the same answer.

My front seal was replaced and now i have the same problem.

 

please?

 

Of all the 700R-4s I've ruined, only one ever lost just overdrive without losing something else. I had it in my '91 RS LO3, but needed it in my C-10, to tow a trailer. So I ordered some TCI upgrades, and put it all together. The truck drove fine, but never did make that last upshift. I removed all the TCI bits, putting the stock bits back, but that didn't fix it, so I don't blame TCI. But I e-mailed them, and their customer service is the worst on earth.

 

I did lose something else. lol. Reverse started going out 3 days ago....

 

This trans is still going, burns the 2nd shift even harder now and shifts even smoother under normal driving. but still no 4th

 

WELL now it seams the front seal gave out.. Joy. Good luck 87tpiz28.. lol