I have a 2000 Ram 1500 2WD Quad. Out of nowhere the tranny started shifting out of 1st gear at high rpm's. Between 3000 and 3500 rpm. Approx. 30mph. It does this with light or heavy acceleration. During acceleration if you let off the gas it will shift, but if you try to accelerate with anything more than a light touch on the gas it tries to, and often does, shift back into 1st. All shifts are smooth and all other gears shift normal. Does anyone have any idea if there is a fix for this and if so, what that would be?
Also, the engine is a 5.2. The number on the tranny I don't know, but I think they only put 1 kind of 4 speed auto tranny in the 2000. The TPS and the VSS have been replaced and the tranny has been scanned. The scan showed no codes. Its been 25000 since the filter was changed. The fluid looks clean. I've heard a little about the shift solenoid but I'm not too familiar with them. I hope this helps. Thanks.