Howling noise from somewhere

Could hear noise when up on jackstands though... and only hear it when moving.

 

No noise at idle

 

If you hear it up on stands then it's in the rear end gear housing or brakes are rubbing. Or front needle bearings

 

have you ever changed the rear diff fluid?

Its likely pinion bearing, moms 07 4 runner had them go bad as the diff oil had never been changed at 110k miles.... it was a howling at highway and really noticeable on deceleration.

Plan for pinion bearings and ring and pinion to be replaced if it is in fact bad

Might replace the CB cus its cheap and easy to see if that solves things.

 

I just changed the rear diff fluid... 144k miles never been touched.

Lot or "or's" in that statement lol....anyway for me to be definitive instead of just replacing parts?

 

Id put money on pinion bearings if that is the case, especially after a fluid change that now has washed all the contaminates that were in the pits of the bearings away... exact same thing happened on my moms 4 runner.

Check your carrier bearing (you can unbolt the two bolts and see how freely and smoothly it spins). If it feels notchy etc replace the CB first, as it would need to be replaced anyways, that will allow you to determine if its pinion bearings or not.

But at 144k of original oil.... like stated its 99% pinion bearings.... and while you are in there your going to want to replace diff carrier bearings and ring n pinion and get the lash set proper.

 

Cb and u joints were replaced about 10k miles ago. Guess it could go bad... what's the cost on a job like this? Sounds like a mess

 

Use a mechanic's stethoscope.

 

Assuming it's a rear wheel bearing because I just can't tell with the stethoscope....with information provided any way to determine which side.

Just a recap. Noise stops when turning right louder when going left

 

Check the right rear wheel bearing

 

My mechanic aka my fatherinlaw had he same thought. I'll keep ya posted

 

Did you jack it up and have someone "drive" it while you listen with the stethoscope? I've diagnosed plenty of wheel bearings and pinion bearings that way.

 

Had it on a lift and around 30mph u could hear it. My fatherinlaw couldn't tel which side though said it sounded like right was louder but wasn't sure

 

Well... finally installed new rear bearing and issue resolved. Took about 3 hours and that included making a puller. Thanks for all the advice fellas.

 

Pinion or axle?

 

Oh sorry. Rear wheel bearing on passenger side.