Noise varies with speed and direction

Hi folks! I have a 2004 F150 XLT supercab, 5.4l engine, towing package.

It’s making a noise I’m having trouble figuring out. Here are the details:
-noise while moving
-varies with speed - starts low pitch; pitch increases with speed (wwwhhhooooooooooooo)
-noise is steady (like NOT wwoooo woooo wooo wooo)
-noise varies in volume depending on which way the wheels are turned - worse to the left, moderate going straight, slight going right
-when stopped, I can turn the wheel all the way left or right and the power steering pump makes no noise or protests
-very very slight buzz in steering wheel when I turn to the left and the noise increases in volume
-noise diminished when going 70mph or so but I think that’s because the wind noise drowns out the higher pitch noise. (pitch gets higher as speed increases)

For other reasons, I’ve had all the wheel bearings replaced, brakes redone including emergency brake, new rear differential, some new steering parts including shocks… trying to think of everything else that’s been done that would be related…

What could this be? At first I thought power steering pump but I wouldn’t think that would vary with speed. Plus it doesn’t make any noise when stopped and if it was going bad, I would think it would protest when I turn the wheel even when stopped. Any ideas?

Thanks! Eileen

Was the noise there prior to replacing the front wheel bearings? Is it 4x4?

Sounds like a wheel bearing, in spite of your previous repairs.

My first guess is a tire problem. Wheel needs balancing, or the tread is separating.

Bad wheel bearning make an awlful-sounding grinding noise, so it doesn’t sound like that to me. The noise you describe sounds more like a differential with low fluid. You could check that fairly easily.

Wheel bearings differ, I just replaced one, It sure could be similar to a tire problem. Sounded like a distant airplane, buzzing in the steering wheel, though I am hypersensitive, new wheel bearing solved the issue. Listen with a stethoscope to determine the problem, I mean don’t go throwing parts at a problem, but correctly diagnose the problem first.

Yeah, wheel bearing usually makes a different sound. Although I do understand that just because it’s new doesn’t mean it can’t be bad.

Tire? Why would a bad tire only make noise when turning to the left? It should be making noise all the time. Plus I just drove 5000 miles across country with the noise plus all the miles in the months it’s been making the noise. I should have added that this isn’t new… probably been making noise for 6 months maybe? It’s starting to get worse. (On a side note: I just had two flat tires on my RV. One flat and then another one about 30 miles later. Doh!!)

I’ll check the differential fluid tomorrow.

Thanks for the ideas. Keep em coming.

I for sure don’t want to have to replace wheel bearings! On this truck, the bearings are non-servicable and part of the hub and rotor assembly. They were about $300 each! Although these may still be under warranty. I’ll have to check that.

Ooops, sorry Rod, missed your post. No, this noise was not prior to wheel bearing replacement. This truck is a 2wd.

I have a similar problem with my '05 Escape 4wd. 110k mileage, the sound started with 4 new tire installation a month ago. I thought it was tire noise since I had bought a different tread design, we replaced the brakes too. The sound is getting louder. Louder with acceleration, when on curve it increases