I've just rescued a 1992 RS with the 3.1L V6 and 4spd Automatic from a wrecker yard impound auction. She's been a little abused and neglected over the past 140,000 miles. The oil dosen't seem like its been change in 20,000 miles and the transmission fluid...I would assume its the factory flluid. Anyhow, the transmission seems to run fine as long as it shifted into Drive, but as soon as I put her into Overdrive, she slips like crazy, won't even go from a dead stop. I have noticed the shift indicator dosen't line perfectly, so I'm wondering if this is a linkage issue or transmission issue. Any thoughts?

 

When you are in Drive does it shift through all four gears? Does reverse seem to be in the right place? Sounds like you cable has streched and your not in the gear you think you are. There should be a adjustment at the linkage. You could also have damaged or loose linkage. Normal when overdrive fails it only effect the shift from Drive to overdrive that happens and 40 plus MPH not while sitting still.

 

In the drive position it only goes through 3 gears and then from what i assume the torque converter locks in (because it dosen't feel like a shift). Also at 70mph the rpm is a little over 3000. Reverse isn't quite in the correct position along with 1st and 2nd.

 

Sure sounds like it's a linkage adjustment problem. Whether your shifter is in 3rd or O/D, the trans still starts out in the same first gear. Since you're also getting slipping from a dead stop in O/D, I'll bet your trans is teetering between being in gear and neutral.