hey,
The first thing I would check is to jack up one front tire and give it a spin by hand.....then the other tire.
Take note of if the CVs turn in relation to the tires and also the front drive shaft.
my guess is the front outer splines at the CV axle (where it meets the drive flange) could be stripped out. Or the CV birdsfield joints could be shot (but this would be noisy)

next guess, is the spider gears in the front diff

third, front ring and pinion (very noisy)

lastly. the transfer case itself (unlikely)



Good luck and let us know what the verdict is


Allan