Tough to diagnose front end noise by description...

[MikeD268]

'99 5.3 Ext cab LS Z-71 4x4 w/280k. Suddenly developed a constant "hum" that almost sounds "gear-meshing" related in the front end. Both front hubs and rear shaft u-joints were done in the last 2-3 years. Front shaft u-joints look rough. Not sure when they were last replaced. "Hum" is definitely front-end, rotation related as opposed to engine acceleration/deceleration as the "hum" increases with downhill speed/decreases uphill with transmission in neutral. Doesn't pull particularly to either side.

No idea on this one and, as cash is tight at the moment and AAA is current, don't want to take it to the neighborhood shop that charges $90/hr and up-charges 30% min on it's parts. Hate to find out the hard way but not many options this week. I know I'm asking the impossible but any thoughts appreciated.

[SleepyHead98]

Maybe brake rub? Are your pads dragging on the rotor? I would have guess hub right off the bat, but.. I dont know. Do you have a sticking piston, do the wheels get extremely hot after a short drive?

I hear mechanics tell me all the time that a hub will go bad if the nut wasnt torqued to specs.

[j cAT]

jack front end off the ground and check out the hubs/cv /ujoints. if all that is good drop front diff oil and see if its damaged gear oil [gray] with metal flakes.

[MikeD268]

Turned out it was a 2-3 yr old max wheel bearing. Go figure. Cheap POS...

[SleepyHead98]

Yeah, Im starting to learn the hardway about cheap POS stuff. Glad you found the problem. Glad it wasnt the transfer case or anything major.

[j cAT]

Originally Posted by MikeD268

Turned out it was a 2-3 yr old max wheel bearing. Go figure. Cheap POS...

use the timken bearings made in USA. stay away from china hubs. cost 2X but the job is done I had Chinese hub POS fail in 16 months.