I have a 1993 Ford F150 with a AOD tranny. When I first start the truck up my tranny won't go in to gear until the truck warms up a bit. After a few minutes it works fine. The problem effects all gears. I replace this tranny about 3 years ago with a used one out of a van. I reused the same converter from my old tranny. The truck has 160,000 miles on it. Any ideas?