High pitch whine at 60 MPH after 5.38 re-gear

[Missouri99TJ]

Have same whining sound. Definitely from the roof rack mount just above the winshield.

Happens right between about 58-61 mph. Goes away if I add or subtract an mph.

 

[Liv2Ryd]

Sounds like a bad gear set up perhaps made worse if they filled the diffs with a synthetic gear lube. It's especially important to run a conventional gear lube during the critical breakin to help the gears run as cool as possible.

I confirmed that they install/used conventional gear lube before and after the regear. No worries there.