All,

I have an '00 SR5 with 220k and I'm in the process of fixing everything, and there's one nagging problem I need your help diagnosing (or at least knowing where to start):

-I get an oscillating whirr/roar sound that corresponds with wheel speed. Whoom. Whoom. A few times a second at 60mph. At 10mph it can sometimes be heard as a subtle knock.

-The sound/knock does not correspond tire rotation speed i.e. it's not 1:1 noise to revolution if that makes sense.

-Not affected by throttle, does it in gear and in neutral and in 4x4, does not change with braking.

-Is not a consistent wheel bearing roar and doesn't change with steering input (I've already replaced one wheel bearing and hub)

-All fluids changed and the old stuff looked good coming out

-Did it on old tires and suspension and now does it on new tires and suspension

-CV boots look good and there's no grease everywhere, though I don't know what they're like inside.

SO...I know it's impossible to diagnose some noise via an internets forum but I'm wondering if anyone has experienced anything like this, and/or what the usual suspects might be in terms of rotating bits and bearings which might need attention in the front assembly.

I've searched and nothing seemed to pop up as a suspect.

Thanks very much for reading my post.