Driveshaft growl with 4.88 at 80+ mph

Folks,

Had 4.88 gears put in a while back. Work great for towing. In the great state of Texas a number of road are 80 mph or more. Get a growling noise in the rear, maybe read diff or drive shaft at 80 or more. 2010 4x4 2.7 5 speed 33 tires, cap on bed several hundred pounds of tools in bed full time. No metal in rear diff (fluid changed every 30,000). Bearing going out somewhere?

Bobby
TIA

 

My bet would be a carrier bearing. Get under the truck and see if you can find any play in the drive shaft.

Also goes without saying that 80+ MPH on 4.88s with a 2.7 and 33's is probably not the best tool for the job. In my opinion, that is a matter of when, not if, you grenade some portion of the drivetrain.