Bad Rear Wheel Bearings??

[The Yin]

Pretty sure my rear bearings are done, but wanting others to have a listen before I spend the time/money on this.

2005 2wd 6v just over 180K.
I put the car on jacks, in neutral, parking brake off and rear brake pads pulled. This is how it sounds when I spin the wheels:
- YouTube

- YouTube

I recently replaced the front bearings and the u-joints, but still hear a bit of grinding/humming noise when driving. Always hard to tell when on the road with wind, tires and exhaust all chiming in.

95% sure it's the wheel bearings, but also planning to have all the diff bearings replaced while I'm at it. Just checking here in case there is some other possible item that can cause this that I'm completely noob to.

 

[AuSeeker]

Pretty sure my rear bearings are done, but wanting others to have a listen before I spend the time/money on this.

2005 2wd 6v just over 180K.
I put the car on jacks, in neutral, parking brake off and rear brake pads pulled. This is how it sounds when I spin the wheels:
- YouTube

- YouTube

I recently replaced the front bearings and the u-joints, but still hear a bit of grinding/humming noise when driving. Always hard to tell when on the road with wind, tires and exhaust all chiming in.

95% sure it's the wheel bearings, but also planning to have all the diff bearings replaced while I'm at it. Just checking here in case there is some other possible item that can cause this that I'm completely noob to.

Hard to tell anything from the video, get yourself a mechanic's stethoscope at most any auto parts store for about $10 and use it to help pinpoint where the noise is coming from, if it's coming from the axle tube right behind the brake mounting plate then I was saying wheel bearings.

The stethoscope will come in handy for other noises I'm sure you will encounter in the future, no tool box should be without one.

 

[dasx86]

Hard to tell, but I think the sound you're hearing is simply the parking brake shoes lightly rubbing against the inside of the rotor

 

[The Yin]

Will do more testing

Thanks for the tips. Just ordered a mechanic's stethoscope, can for sure use that elsewhere.

I'll test again with the stethoscope and see if I can isolate the area. I'll also test with the parking brake slightly applied to see if the sound changes. Would be nice if it is just a brake issue.

 

[AuSeeker]

Thanks for the tips. Just ordered a mechanic's stethoscope, can for sure use that elsewhere.

I'll test again with the stethoscope and see if I can isolate the area. I'll also test with the parking brake slightly applied to see if the sound changes. Would be nice if it is just a brake issue.

Just an FYI, many times when a rear wheel bearing is bad it will also make the seal leak, so look for gear oil around the rear brakes.

Let us know what you discover!

 

[The Yin]

More Testing done.

I finally got some more testing done.
The drag/scrape sound in the video was indeed from the parking brake.
I used the stethoscope to try and test and couldn't tell for sure. But I also just pulled the rotor and the sound was not there when spinning with the rotor off.

Seemed there was a build up of brake dust, but also a small bit broken off from the edge of the pads.

I did however find a very small amount of gear oil leaked behind the rotor on the passenger side. Bone dry on the driver side. Might need more work in the future, but seems wheel bearings are fine for now.


On the other hand, new worry sound unlocked. Never heard it before, but there is a gear "rumble" sound that seems to be coming from the Diff (used stethoscope to trace) when I spin the wheels. But I think it's only if the tranny is in park and the diff is doing diff things so that the 2 wheels spin in opposite directions. Full noob on diff work, so not sure if it would make sounds like that when operating normally in certain conditions.


For now thou, just going to replace the brake parts and keep on truck'n

 

[Lemming]

I finally got some more testing done.
The drag/scrape sound in the video was indeed from the parking brake.
I used the stethoscope to try and test and couldn't tell for sure. But I also just pulled the rotor and the sound was not there when spinning with the rotor off.

Seemed there was a build up of brake dust, but also a small bit broken off from the edge of the pads.

I did however find a very small amount of gear oil leaked behind the rotor on the passenger side. Bone dry on the driver side. Might need more work in the future, but seems wheel bearings are fine for now.


On the other hand, new worry sound unlocked. Never heard it before, but there is a gear "rumble" sound that seems to be coming from the Diff (used stethoscope to trace) when I spin the wheels. But I think it's only if the tranny is in park and the diff is doing diff things so that the 2 wheels spin in opposite directions. Full noob on diff work, so not sure if it would make sounds like that when operating normally in certain conditions.


For now thou, just going to replace the brake parts and keep on truck'n

I had a noise in my rear end like youre describing. I changed the oil to 75w-140 and added a bottle of Bar Leaks Diff repair. It quieted the sound down for 5K miles. But, it did not fix my problem. Im currently waiting for my 4R back while a shop is swapping out the rear axle with a used unit.

 

[sam_KOR]

Grinding or humming when spinning the rear wheels with brakes off usually means bad rear wheel bearings, especially at 180k km. Since front bearings and u-joints are new, focus on rear bearings first. Diff bearings make noise under load, not free spin. Replace rear bearings before spending more on the diff.

 

[jreask]

I took my 2006 to the local differential experts and took a test drive. Less than a quarter mile later the expert told me it was definitely a ring and pinion. I bought a rebuilt pumpkin from ECGS and changed it out in about an hour. $700 later I still had a humming noise. I put the truck on 4 jack stands and let it run. The noise was most definitely coming from the right axle somewhere. $135 later with a new wheel bearing pressed on, the noise was gone..now I have a new RP and a new bearing. It’s possible it could be your problem. Does it hum at ALL speeds?

 

[rdruss]

I took my 2006 to the local differential experts and took a test drive. Less than a quarter mile later the expert told me it was definitely a ring and pinion. I bought a rebuilt pumpkin from ECGS and changed it out in about an hour. $700 later I still had a humming noise. I put the truck on 4 jack stands and let it run. The noise was most definitely coming from the right axle somewhere. $135 later with a new wheel bearing pressed on, the noise was gone..now I have a new RP and a new bearing. It’s possible it could be your problem. Does it hum at ALL speeds?

Thanks for confirming "local diff experts" not always "experts", except at getting your $$.

 

[Buckaroo]

Rear diff noise is typically a whine that changes when you coast versus under load. I was chasing a noise a while ago and just couldn't verify where it was coming from. I bit the bullet and bought a Chassis Ear (STEELMAN PRO Chassis EAR 2 Auto Diagnostic Noise Finder), the wired kind which is about $140 on Amazon. The wireless version is a lot more and you don't need it. Verified immediately it was the right front wheel bearing. Used it recently to isolate a suspension noise on a Honda Accord - rear end link squeaking. I don't use it often but when you need it, you need it - particularly as I get older and my hearing gets worse.

 

[The Yin]

I took my 2006 to the local differential experts and took a test drive. Less than a quarter mile later the expert told me it was definitely a ring and pinion. I bought a rebuilt pumpkin from ECGS and changed it out in about an hour. $700 later I still had a humming noise. I put the truck on 4 jack stands and let it run. The noise was most definitely coming from the right axle somewhere. $135 later with a new wheel bearing pressed on, the noise was gone..now I have a new RP and a new bearing. It’s possible it could be your problem. Does it hum at ALL speeds?

Hard to tell since the hum is not very loud. When driving on road I also hear tires and my loud exhaust.

When I last tested, what I was hearing was near the Diff, but only when in Park so that when I spin one wheel forward, the other spins backward. I couldn't get the same noise when it was in natural and both wheels would move.

I would have to test again with wheels off the ground and leave it in drive. That why I could listen when wheels are spinning at 30 or 40 MPH.

For now it drives without issues, aside from the light noise.


That being said, I am looking at replacement options for the bearings and the diff. Thinking I will pull axles and bring to local shop for bearings. And for diff, replace with one from ECGS.
May just hold off until close to or at 200k, unless something changes indicating a more urgent need for replacement.

 

[Buckaroo]

May just hold off until close to or at 200k, unless something changes indicating a more urgent need for replacement.

I think that is an excellent idea!