[Sid51x]

Hey all,

I've done a little searching about the forum, and it pointed me a few different things that 'could' be the issue. Such as excessive rust in/around the brakes/dust shield rubbing up against the rotor, bent portions of the wheel hub's mating surface, dragging brakes, etc...

And this does not appear to be any of those.

While driving there is sometimes a slight speed dependent grinding noise that appears to becoming from the rear passenger side. It is more pronounced when making left turns, more so when the suspension gets loaded (Sharp quick turns). The sound does not appear to be there when making right turns.

It is not a constant noise, instead it comes in waves, such as a certain portion of an object coming into contact with something it should not only when it passes, though it does not appear to happen in time with what I'd assume to be a rotation of wheel would be, it's just slightly off.


Info: 183k on the clock, LSD in rear appears to be in good order, New OEM driveshaft (~ 10k miles ago), The silicone differential bushing reinforcement trick has been done (got rid of the bucking sensation on hard shifts, which was amazing.) The Rear CVs/axles have not been replaced to my knowledge. Brakes were done by myself (OE parts) about 30k miles ago. Foz is sporting a ~ 1.5" lift with standard height king springs, and a strut top spacer kit, this was installed ~ 50k ago.


Troubleshooting so far:

1. Wheel bearing tests (Both sides):
   1. Up in the air, try to move tire in any direction it is not supposed to : Passed
   2. Remove tire, and rotor, move hub by itself feel for roughness/play, listen for weird noises: Passed
2. Brake Tests (Done on both sides):
   1. Removed caliper assembly, cleaned it out, reset the pads, no issue operating the piston: Passed
   2. Removed Rotor, eyeballed flatness, removed crud, Checked for wear marks: Passed
   3. Installed rotor, turned hub listened for noise: Failed
      1. Found slight wear marks on dust cover, ground some material away
      2. Found some built up rust on Dust cover, removed
      3. Found some rust on that lip that mates with the rotor on the hub, removed
      4. Found some spots that felt like they were bent, ground away anything that felt "off"
   4. Installed rotor, turned hub listened for noise: Pass

So it seems to me, that there is something here that is over my head and may need to being in a profe$$ional. Before I go that route, is there anything else that someone might know/think of off the top of their head?

 

[Dogs]

Is the sound a mix between, a gurgling sound (like the grinding, but not as sharp), and a worn wheel bearing?

Does, your diff have the sundial on the side?

It could be the backlash in the Diff. There are two gear backlashes that can be set. One requires shims, the other requires preloading the carrier bearings.

 

[Sid51x]

Oh geeze, I hadn't even considered the Diff being the issue. That's a whole other can of worms.

The diff has those rings around it with the 5 bolts.

I'll see if I can get a video instead of going back and forth with descriptions. But I can see where that sound may come from.

 

[Sid51x]

As a follow-up for this, Did get it into a mechanic.

The rotor choice I made, the CENTRIC 12047011 as an OE replacement has a ring on the inside the partially interferes with the backing plate on the rear hubs. This ring comes into contact with that lip when the vehicle is under load.

Not the best thing in the world, but nothing super detrimental either.

Options appear to be turning down that rotor, or replacing it with an OEM per the mechanic.

 

[Kevin]

Thanks for the follow-up @Sid51x