Need help on my Silverado.. Grinding.. Whirring sound up front in 4WD

Let a local shade tree mechanic, a friend or neighbor with some mechanical abilities help you detect the problem. Hope it doesn't happen to you like it did to me.....my GMC kept acting up until it died on the road, but then nobody could find the problem and still haven't. It's still dead. Whatever it is will get worse until it ruins something else like a rear or frontend housing, transfer case or wherever the problem exists and then you'll be walking.



You've already changed the hubs and that should have included new wheel bearings in the front if they did it right. That should eliminate that source and leave you to suspect the front differential, the CV joint shafts or the transfer case itself (doubtful on that). A lift on a hoist and inspection should help to pinpoint the problem. I had a 99 GMC halfton 4x4 with a growl that we never did detect. Traded it off. Let us know the outcome.