Originally Posted by
Horatio
Gear diffs 'bind' as much as the chosen diff oil dictates.
The 'bind' that occurs in a loaded gear diff is mechanical and the lightest fluid weights don't make it go away. It is the reason that they cannot replace the ball diff in 2wd off road. If silicone fluids with much better film strength and hear resistance were to be created, this could probably be improved upon. This inherent bind seems to be beneficial on the high grip surfaces where gear diffs are favored.