I’ve been a member around these parts for a long time but haven’t posted much because my 5th gen is just so damn reliable!

I posted yesterday and got some great feedback and strategies to deal with front tire cupping. Now I’m moving on to figure out another issue that surfaced.

I’m getting a metal on metal rubbing noise from the rear. Appears to be from the wheels. I recently did pads and rotors all around but this noise is relatively new. I lifted the rear axle and put the car in drive to get the rear wheeLS spinning in the air and the sound wasn’t there. Under weight of the car and driving, the sound is there.

Before I pull the rear brakes apart and look for any rubbing, thought I’d ask and see if there are other ideas or others that have had this issue.

Bent dust shield around rotors?

My guess is probably not it since you have zeroed in on the rear wheels, but there was/is a rash of us that had strange noises that ended up being the hood latch. Tiny dab grease and it's gone.

The 2nd bizarre noise some have reported is squeaking from the mud flaps, the plastic pop rivets. I didn't have this one, but was surprised when a few reported it. I doubt this is it either, since you said sounds like metal on metal.

Quick way to try and source a squeak is get old spray bottle filled with water. Spray down just one area and drive it. Still hear it, try another likely area. Usually the water will stop the squeak and help you pinpoint the source.

There's nothing worse then the random noise that is hard to locate.

Definitely not a squeak but like a rotational tub. Metal on metal sound. Going to pull some wheels later this week and start checking stuff off the list.

This one is my guess.

Recheck your brake work. Dust shield could be bent during install of brakes and wheels but unlikely

Update here: pulled both rear brakes apart and everything looks as it should. No signs of rubbing, parking brake shoes and parts look good. Stuck my phone down there on a mount, pointed at the diff, but could capture the sound over the tire and engine/exhaust noise. Tomorrow I’ll drain and refill the rear diff so I can inspect for any metal shavings or glitter but fearing I have a bad bearing.

No leaking fluid, which was an issue on the 3rd gens indicating the common rear axle seal.

Will keep everyone posted.

My 4runner does not tow and I am by the literal book using the “Dirt Roads/ Off-roading” schedule about maintenance. Will be disappointed if there’s a part failure. Holding out hope it’s something dumb that I’m not seeing.

Update here: diff fluid looked brand new and had no glitter, flake, debris etc. Refilled, greased the propeller shafts and went for a drive. Sound still there.

Any ideas?

I had an odd squeak/metal groaning sound and it ended up being a bent axle shaft. Below is the video that I compared a recording of my sound to which led me in the right direction. When mine was on a lift, there was a slight wobble to the wheel when the wheels were spinning. There was no noise when on the lift.

https://www.youtube.com/watch?v=UzAuhlLlvyI

I’ll try again with the video. Mine is definitely not a squeak or that loud. It honestly sounds like a brake dust plate rubbing and i was surprised not to find that to be the culprit.