th350 shifting problems, It woun\'t engage 1st unless in low????? I have a th350 tranny. It all of a sudden started acting funny. It works fine in reverse, but if I shift to drive, I can feel it engage, then slip and act like its in neutral. I thought it was low on fluid, but its not. I found out that if I pull the shifter down into "low 1", the tranny will engage first gear and hold. I then can accelerate and then shift into drive and the tranny shifts fine. That is until I slow down enough (2-3 mph) and it will slip and act like its in neutral again. But then I pull it down into low and I'm off and running. Whats going on? I checked the shifting linkage, and it is adjusted correctly. I have never heard of a tranny slipping in a gear, but when shifted to low, act fine. Can anyone shed some light on this for me?