First to say hi to everyone since i'm new here, second, I just bought a 91 dodge ram 318 tbi 4 speed tranny long wheel base. The 4x4 keeps kicking out of 4hi, it works fine in 4 low, but every 30 or so seconds in 4 hi it keeps jumping out and grinding, some of the times it has went right back in, a couple of times I had to throw it back into 2wd. Above the sunvisor it has instructions to put it in 4hi while "MOVING" so I guess it has the Ram-Trac t case in it? Any help on this would be nice. Thanks.