Mitsubishi Repair: 1993 Eagle Summit 1.8L Auto-Trans Problem, overdrive transmission, eagle summit

Question
Changed fluid/filter in automatic w/overdrive transmission.
In retrospect- may have purchsed wrong fluid at auto parts store(had to go to dealer to get fluid for 2003 Lancer). Some weeks later, trans messed up. The car will run forward in first 2 gears with very harsh up/down shifts, 30-40 mph maximum, no reverse at all. Could changing the fluid/filter using the dealer supplied/certified trans fluid possibly improve the transmission performance? Trans has 140k miles. No significant prior problems.

Answer
Kent: What color is the fluid now? Pink in color? Pink/brown in color, all brown or black color with a burnt smell? I guess I would again change the fluid and filter then add a transmission conitioner(get that at most parts stores) as that is a cheap fix right now. Other wise try having the computer coded to see what it might kick out as the problem with the transmission. As the computer controls a lot of the shifting in the transmission. If it gets really bad the computer will put the transmission into a "safety mode", and the transmission will be stuck in second. I would change that fluid and put in the right kind of fluid for your car. See these little cars, the transmission gets super hot and so they need a fluid that can handle that heat. Most fluids on the market don't. So you need to have the right kind, but don't put this off. Because other wise you will damage those clutches inside the transmission. Then all that will be left is to rebuild or replace the transmission. Hope this helps and God bless: Linda