So, I went out and bought some mudder tires and of course the "Free
Replacement Warranties".  I had to collect on one due to an improper placed
nail. They put a new tire on the right front and said I'd be okay ( I have
the AWD ) beings the tread depth difference was only 2/32nds between the
right and left.

Not too long after that, I started experiencing a deafening roar from the
front. It gets really loud at about 40mph, then goes quieter, then back to
obnoxiously loud at 70mph.  I tried to pass it off on the mudders and tried
to remedy that with new less aggressive tires, with no luck of ridding the
noise.  It's an '01 (born 07/00) AWD 5.0liter.  Am I looking at new axle
shafts, bearings or what?

Any help is very appreciated!
Thanks