I have a 2003 4wd Sierra auto Z71 with 116K miles which has front wheel noise. *Tires are ok *noise is loudest about 35 to 45mph, sounds like maybe you are running on rough pavement *noise does not change in 2wheel drive, 4wH, 4wL, AWD or neutral (has automatic button 4wheel drive shift) *changed both axles lube and transfer case lube, no change I am thinking this is front bearings, CV joints? or front differential??? Thoughts? And how do you differentiate to pinpoint the problem? Much thanks for any ideas or suggestions.