I've got the same problem, sounds like a wheel bearing going bad, not the needle bearings. I just replaced the passanger side hub/ axle and needle bearings and seals, but this was a very noticeable growl washboard sound. Maybe the harmonic balancer /It should be a real bad motor shake. I greased my spline shaft and this did nothing. The next thing to check out is my transfer case any sugestions. Sometimes when I shut it down it shakes and makes a sound like somethings comming apart but nothings loose.
