On reflection!! I got stuck in deep sand last week, when I changed down to 4WD Lo the lights showed that I was in 4wd lo, I put the shift into (D) and applied the gas slowly and was going nowhere, Put the shift back to (N) and repeated the process this time "puting the pedal to the metal" It Jumped out of the hole I was in with a clunk, the above symptoms appeared after this event , I guess I never noticed due to the fact that I didn't have to dig it out. does this throw any more light on the subject.

Thanks