I own a 1994 Ford Ranger Supercab (6 Cylinder) and when I start my truck and shift into drive, the truck acts like it doesn't want to shift forward and It makes the engine strain and rev up before finally going forward. I have the same problem when being at an incline. I will release my foot off the brake and the truck will start rolling backwards (when in DRIVE) as if I'm in reverse. I have to hold the brake and push the acceleration peddle for it to shift forward and drive. Any ideas on this problem?