Here is the run down. I have a 1999 Ford F-150, 4x4, 5.4L V8, XLT. It's an automatic tranny. It has a stick to shift into 4X4 (not a switch) and 4H works just fine. Once it goes into N the engine revs high and I'll wait for it to go down.Then try to put it into 4L and it makes this horrific grinding noise. I don't know if I'm doing something or if it's broken and I also put the tranny in N too.