Contour Enthusiasts Group Archives Forums General Troubleshooting Once again another transmission problem

I have a 1995 ford Contour LX 2.0 s4 with 115000 miles, during short trips it shifts fine but for any trip over 30 miles shifting gets real erratic and will sometimes just disengage. I suspect that this is overheating, does this sound right? also I have been told that once a transmission starts to slip that it cant be saved, this dosent really sound right as the tranny is fine for short trips (absouluty no problem). Do you folks think that a tranny flush/fluid change would help? Thanks all.