What is this noise from rear?

[ElmerSabu]

Hello, I just replaced my rear diff and put everything back on correctly including replacing seals. I have no leaks and no clue what this sound could be.

http://youtu.be/sVNqnz_4OZ8

Any help would be greatly appreciated

2002 Ford Explorer v6 SOHC 4x4 xlt 4 door. 170k miles on car and engine, 81k on transmission

 

[TechGuru]

This video is private.

Sorry about that.

But lets go over the basics.

Did you replace just the bearings or the ring and pinon also?

Did you use a dial gauge and shims to adjust properly and use paint on the ring to check contact pattern?

 

[ElmerSabu]

But lets go over the basics.

Did you replace just the bearings or the ring and pinon also?

Did you use a dial gauge and shims to adjust properly and use paint on the ring to check contact pattern?

Hello, thanks for responding. I didn't rebuild any of the new differential. I replaced it with a used one. The noise is not coming from the rear diff. It sounds more like the hub area on the passenger side. I used the old axle from the bad diff.

The video is public now. Sorry about that.

 

[TechGuru]

Well I've never heard a wheel bearing make that high pitch of a sound.

Almost sounds like wind whistle noise from a leak somewhere.

Jack up the rear and check for dragging from service and parking brakes (whole rear if LSD).

If all that checks out I'd look for leaking door seals on the rear doors and rear hatch (and window).

Curious, see if changing the a/c between norm and MAX (outside vs inside) changes the sound any.

 

[ElmerSabu]

Once again thank you for all your assistance and time.

More background on it.

This morning I drove to work with it (23 miles).

On the first leg of the trip I drove 6 miles @ 50 MPH with no noise. I got on the interstate and got up to 70 mph. After approx. 45 seconds no sounds and then it started. The sound does not go away until I would get below 35 mph but then would start again when I would get back to 50 MPH. when I pulled into work I could hear it at very low RPM's (previously had not) and it was clearly coming from the passenger axle /hub area.
I am thinking that the sound starts at certain temperature as the bearings / hub heats up. This morning it was 41 F.

It could be the ABS. I'll check cables tonight after work.

Anyone else have suggestions please throw them in here. I'm willing to replace / fix / grease any component but I'd like to pinpoint what it is before I pull the axle again.

 

[TechGuru]

Almost sounds like a squealing belt or tire.

How is your wheel alignment?

BTW is your diff a limited slip?

Are you going perfectly straight when it makes this noise? Does going around a curve change it any?

I would say put the rear end on stands and run it up to 60mph and see if it makes the noise but since it is a 4x4 you'd have to put the whole thing on stands unless you disconnect the transfer case electronic clutch.

 

[ElmerSabu]

Almost sounds like a squealing belt or tire. Not a belt or tire. Tires are brand new. Less than 5k on them

How is your wheel alignment? I'm not sure what you mean by this. do you mean the alignment in the back or the front? How could it be off?




BTW is your diff a limited slip? LS

Are you going perfectly straight when it makes this noise? Does going around a curve change it any? Perfectly straight, doesn't change on curves/ turns

I would say put the rear end on stands and run it up to 60mph and see if it makes the noise but since it is a 4x4 you'd have to put the whole thing on stands unless you disconnect the transfer case electronic clutch.

UPDATE: Drove home today (23 miles) and the sounds didn't start until after 9 miles @ 70 mph going straight. It continued all the way home until i stopped at a light. Once I started from the light there was no noise. But when I was approaching the light it kept doing it and you could hear that it was directly related to speed of the rotation of the hub/tire.

It feels like it is related to heat due to the rotation at the hub/axle. Almost as if one of the bearings inside CV joint on the axle freezes and then after it stops spinning it unlocks itself. Which is the opposite of how I understand how bearings work.

 

[ElmerSabu]

UPDATE:
I reached behind the hub and grabbed the emergency brake cable right where it goes into the hub. I gave it a good yank and one of the levers pulled back. After that I drove again 23 miles to work and it didn't make the sound, however it was quite a bit colder this morning and I didn't get a chance to stay @ 70mph for more than a few minutes.

We will keep you posted to see if what I did fixed it.

Thanks!

 

[ElmerSabu]

UPDATE:

Still doing it. I can't figure this out. It's so intermittent.

It's driving me insane!!!!

 

[ElmerSabu]

:bump: anyone else want to take a guess?

 

[cudabnu]

Brake backing plate bent a little, and when at speed wind bends it to touch the disc?

 

[ElmerSabu]

:Bump:

Still making the noise, sounds like it might be getting worse.