Noise from Wheels - Cannot tell if Front or Back

Some Background:

I have a 2001 Toyota Tacoma, 3.4 L, V6, 264,000 mi.
August 2022 - new struts.
October 2022 - new rotors, new rear shocks.
December 2022 - new front brake pads.

The Problem: At low speeds I detect a faint metal-on-metal sound that appears to be coming from the area of the wheels.

I cannot tell if the source is the front wheels or the back.

At about 30 mph I start to hear a whistling noise. The best comparison I can think of is a jet airplane that is taxiing on a runway. The noise does not get louder as speed increases. It goes away if I slow to < 30 mph.

My Question: What are the likely causes for this?

My best guess is this is coming from one of the front wheels, but as indicated above, I cannot say for sure.

The guys who helped me replace the struts might have bent the dust shields on the brakes, but I cannot tell for sure if the shields are rubbing against a wheel or something.

When I changed the brake pads last month I saw nothing loose, nothing out of place, and nothing sticking out, but with the wheels removed from the vehicle it was hard to tell if a dust shield was wonky.

My concern is this might be something off-radar, or something to do with the rear end / rear wheels.

I checked out a video where a guy recorded the sound of failing wheel bearings (growling). The sound my truck is making does not sound like that.

I appreciate whatever input you can offer -- I am out of ideas.

This site has helped me get a lot done on my truck without having to take it to a shop, so thank you in advance.

 

You didn't mention if you are 4x4 or not.

Let me start here: If you put the front up on jackstands, and rotate the wheel by hand, do you hear the noise?

It could be:
Pads dragging on rotors - If you pull the pads and rotate the wheel, do you still hear it? Some contact between the pad and rotor is normal when the brakes are not compressed. Depending on the pad material (semi metallic, ceramic, etc) you might hear this as a metal on metal noise.

CV axles if you're 4x4 - The check would be something similar pulling the CV axle and rotating the wheel (NOTE: DO NOT DRIVE A 4WD TRUCK WITH THE CV REMOVED. The wheel will fall off)

Bearings- I know you've said you don't think it's bearings, but I had more than one shop tell me my front bearings were fine when they were completely toast.

Then you gotta start looking at things in the rear drive line. u joints and carrier bearing are easy targets, but it could be the pinion bearing, diff side bearing, rear wheel bearing, or something in the rear drums.

Rotational noises are very hard to track down.

 

Thanks for the info.; the truck is a 2WD, so that box can be checked off.

Much appreciated.

Before I put new pads on the front, I did lift the front wheels and turned them — there was a mild metal on metal sound. I have not tried again since I put the new ones on, and have not checked the rear wheels.

 

I just noticed this. It is never a good idea to mix and match brake work like this. You didn't do yourself any favors by installing new rotors with old pads. The pads and rotors have a bed in (break in) period. Doing things outta snyc like this can cause premature failure of either component and / or bad brake performance.

If you are planning on reusing existing rotors with new pads they need to be turned.

 

The original plan was to do both, but had the wheels off and discovered they sold me the wrong sized pads. I put new ones on as soon as I could get back to it.

 

I'd just get the wheels off the ground and just turn them and see what you find. Be safe, use appropriate jackstands, and jack points.

 

Copy that. Thanks.