It's either the Drive Shaft Carrier Bearing or a Front Wheel Bearing. Intermittant RPM noise based on ground speed of the truck.... not engine rpm's.

Anyone had to replace wheel bearings at 90,000 miles?

RJ

 

Still could be a Wheel bearing.

Jack up the front end and check it like you would a ball joint or tie rod end.
maybe spin it by hand and have someone listen, do each side for compairison.
check your U Joinst as well, I've seen them cause some funny noises.

dan

 

I'm just starting to get a noise....it's not all the time.
Guess what I'm really asking is How many miles are members getting out of front wheel bearings on 4x4's?

RJ

 

I thought mine had a noise coming from the right front, but it turned out to be the right rear wheel bearing and race. Had the seal, bearing and race replaced and all is quiet.