Ive got a 1990 f-150 That I use primarily for a work vehicle. Early this winter it got so it wouldn't go into OD it would just stay in drive. Then within the past few weeks when Im goin over 55 it wants to keep down****ing into 2nd and I have to slow down and let it go back into 3rd and Stay under 55 so it wont do it again. Any ideas guys ?