I am not sure we are on the right path here. Lets do the following (I kibitz, you do the work. I'm not driving to Denver <img src="/forums/images/graemlins/smile.gif" alt="" />)

1. Jack up both rear wheels and put it in park and rotate one wheel. Report what the other wheel does.

2. repeat above in neutral and report results.

3. Jack up all 4 wheels and put it in neutral and tcase in 2wd and rotate a rear wheel, and report if one front wheel turns

4. shift to 4hi and repeat 3 and report back.

Ebrake must be off for all tests. I'd turn the key on for each, then repeat test with key off. Humor me...