Road noise from diff above 30mph

04 4x4 double cab A/T. 140000 mi

Brought in to local mechanic for road noise. They diagnosed it as a shot center bearing and replaced the two piece driveshaft with new center bearing. Road noise improved but still present. There was more than one problem it seems.

Brought it back and they said the diff is the cause of the remaining noise. They said there isn't much to be done besides source a low mileage used diff or find a place to rebuild it or see what a dealership shop says. They said the fluid levels were fine and we agreed changing diff fluid was not going help so left it.

Video of the issue with sound https://youtu.be/qxIouHTKFwk.

Its a howl that sounds like engine braking, but it definitely is speed dependent, not RPM. It doesn't seem to change with load / coast or steering. Pretty consistent above 30mph.

Confirmed the sound appears to be coming from diff.

Any recommendations on what to do?

 

If you're handy, pull the 3rd member and send it to ECGS (they do rebuilds with core swaps if yours is in good enough shape) or another gear shop if you have someone local you trust. There are a few bearings in there... Pinion and carrier bearings. There are also wheel bearings pressed onto the axle shafts themselves. I'd have to be pretty sure it was only the pinion/carrier bearings or only the wheel bearings just to do one or the other- said plainly: you should do both at the same time. You're going to have to pull the axle shafts anyway to get the 3rd member out.

 

I can not open You tube videos in less then like 30 minutes

You have ruled out the tires A 100 percent .

Some sure can make noise it would not hurt to try another set see if things change .

I had a set the right pressure and ambient air temperature I though The differential was going to explode in a mile or less.

 

yea just pull the 3rd member and take a look. If the bearing is shot youll be able to see it once you crack it open. Its kinda hard to really diagnose the issue without seeing the insides

 

Time for a regear and front locker.