Grinding from rear. Bad wheel bearing?

[seeking3rdgen]

After a long road trip to Moab, my '03 developed an unpleasant grinding sound in the rear. It seemed to be coming from the driver side only, but now both sides make the sound. While driving, it sounds like grinding, but changes to more of a (hard surface) rubbing sound when I brake.

I had assumed it was the rear brake pads and wear indicator, but when I went to change the pads, they are fine, and the axle makes the exact same grinding sound even when the brakes are totally disassembled. Nothing appear to be bent out of shape or rubbing externally.

Do I need to replace my rear wheel bearings?

Thank you!

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[djpope09]

Have you pulled off the rotors to check the parking brake?

 

[seeking3rdgen]

Have you pulled off the rotors to check the parking brake?

I haven't yet. I didn't realize that was a possibility. I'm reading about it now and looking for a good write up.

 

[djpope09]

Follow this write up:
4th Gen 4Runner Rear Brake Rotor and Pad DIY

It can be hard to tell if you're actually rotating the star adjustment wheel since you can't really see it. You'll hear the springs in the parking brake relaxing if the star wheel is rotating, it doesn't take much force. I found that it moved better if I was more gentle with it.

The parking brake adjustment section in this link shows you what it looks like. Rotate it down to loosen, rotate up to tighten.
Rear Parking/Emergency Brake Shoe Replacement Instructions | Toyota Nation Forum

Just make sure the parking brake shoes are backed all the way off before you try to pull off the rotor, otherwise you'll mess up the shoes and end up replacing some hardware.

I had some bad grinding from mine recently, but from the pads being too worn down. Even with all the hardware off mine sounded like yours. But I put new pads and rotors on and put it back together and couldn't hear anything when driving.

 

[seeking3rdgen]

It does seem to be parking brake related. When I took the discs off, the grinding sound goes away. The parking brake all seems to be in working order, but is rubbing for some reason. I dialed the parking brake back using the star gear and the disc seems to be spinning freely now. New discs go in tomorrow.

 

[Nahrah]

It does seem to be parking brake related. When I took the discs off, the grinding sound goes away. The parking brake all seems to be in working order, but is rubbing for some reason. I dialed the parking brake back using the star gear and the disc seems to be spinning freely now. New discs go in tomorrow.

It can also be the parking brake shoe hardware. If you pull out the disc without backing out the parking brake shoe, you can stretch the pin and spring enough to rub it on the axle hub. Especially the right retainer pin, since it has a "u" bend to it.

 

[seeking3rdgen]

The passenger side seems to be fine now, but the driver side is still rubbing with the new rotors. The parking brake pad seems to be rubbing in the 10 o'clock or 11 o'clock area, but only for about a third of the rotor's rotation. This is despite having the parking brake star gear adjusted all the way downward. The parking brakes both appear to be in full working order, but I haven't opened it. I have a parking brake kit, but it looks like a bear. I have everything except for new shoes. Is there anything else left to check or adjust before disassembling the parking brake?

 

[djpope09]

The passenger side seems to be fine now, but the driver side is still rubbing with the new rotors. The parking brake pad seems to be rubbing in the 10 o'clock or 11 o'clock area, but only for about a third of the rotor's rotation. This is despite having the parking brake star gear adjusted all the way downward. The parking brakes both appear to be in full working order, but I haven't opened it. I have a parking brake kit, but it looks like a bear. I have everything except for new shoes. Is there anything else left to check or adjust before disassembling the parking brake?

I would look at both sides of the vehicle to see if the side that's rubbing is missing anything that the other side isn't. And yes, replacing any of that hardware by yourself really sucks. Either get a parking brake tool from Harbor Freight or get a friend to help get everything back in place.

 

[seeking3rdgen]

Without disassembling the parking brake, everything appears to be the same on each side. Everything is in place and seems to move correctly.

 

[seeking3rdgen]

I went ahead and rebuilt the driver side parking brake. What a huge pain in the ass that was. It was silent through preliminary testing. We'll see how it goes tomorrow when I put the caliper and wheel back on. As challenging as the driver side parking brake was, I think I'll go ahead and rebuild the passenger side tomorrow.

Thank you for the help!

 

[seeking3rdgen]

I put the rotors and wheels back on, and it's still grinding / rubbing. It's not as bad as it was, but it's still making contact. I did the full parking brake rebuilt, but with the stock pads since they look fine. When I take the rotor off, I can see the rusty residue left from where it makes contact with the parking brake shoe.

This is maddening. What is there left to do? Talk me out of just removing the parking brake...

 

[seeking3rdgen]

Hmmm. After pumping the parking brake a few times, it's gone back to silent. I noticed that the parking brake can swivel some in place. Is this a self-adjustment or something?

 

[djpope09]

It sounds like the springs pulled the shoes into place after your rebuild. I think you're fine to adjust the star wheel to pull the shoes out a bit so they fully engage when you push the pedal.