2004 S-10 Blazer, 56,000 miles. Driving at all speeds I have an awful grinding/humming noise coming from the right front. Noise is constant at all speeds and when turning. Noise goes away when the 4wd is engaged. Left hub was replaced in august under warranty due to ABS activation. I just replaced the right hub tonite for the same reason. Noise is still there. Turned onto my road tonite in 4wd, felt clunk, and the noise seemed to go away in 2wd. I can't seem to duplicate the problem now. I had it at the dealer a couple of years ago for the same noise. There was a TSB stating that the front axles were 1mm - 2mm to long and riding against the front differential spider gears. The dealer ground down the left axle 1mm, raised the torsion bars a bit, and everything was fine until now. Checked the front differential oil and didn't fine any metal shavings. Are there internal bearings in the differential? Bad axle? Bad front pinion? Axle somehow staying partially engaged? Need help! Really stumped by this one!

 

This perhaps:
4wd Front Axle Clicking When in 2HI - Goes Away when in 4HI/4LO

 

89 chevy blazer makes knocking only turning left