sometimes when starting to move the truck will not go and sounds like a gear is out of time or brakes locked up and not quite letting loose. loud banging noise. sometimes you have to put it in reverse and back in drive to clear the problem other times you will have to rock it back and forth from drive to reverse. A factory rebuilt transmision was installed 25000 miles ago and the 4 wheel drive appears to work fine. I need help to fix this please.