Eaton Grinding

If it just showed up after the diff was done and it didn't do it before, I'd suspect it was the diff. Could be ring and pinion too tight/loose. Could also be incorrect pinion depth, pinion bearings/carrier bearings incorrectly adjusted.

 

If you press in the clutch does it go away?

 

CK. the easy things 1st, Is the air ride Hight on the rear end higher or lower than it was before rears were rebuilt? a little change in ride hight can make a lot of sounds like you are hearing?

 

I'd look into the ride height thing too. Especially since they were just working in the area of the suspension valve. Go under and take a look at it (it's a valve gizmo with a lever going to the frame which then feeds air to the suspension or takes it out, depending. They probably had to take it off, or shove it out of the way. They may not have set it back at the same position as it was previously. If this is the case you can do one of two things, you can adjust it slightly up, or down, and go for a little test drive, until you get it right. I had to do this on a Volvo once. Or, you can get the frame to diff distance from a dealership and then go under and measure, and set it to specs. If this isn't the problem, I would then go from there with further diagnostics, as NM said, maybe the diff itself.

 

Something else to check would be carrier bearing,if they left a shim out I think it would be constant,but you never know.

 

Have a 2011 Volvo 670 vnl with isx15 13 speed.
Changed shifter bushing cus it went bad. grinding noise on reverse, 6 low 7 low and 8 low.
Any suggestions? It wasn’t grinding prior to the change of the Bushin

 

How can you change the pinion angle ?
That’s usually set by the spring (airbag) perches which are welded to the axle .