As I think others have mentioned I don't see the 5x9x0.1 for the gear diff. I noticed a drag of the outdrive on the Gear Diff case so I used an exacto knife to take a little material off.
I filled my diff with losi 15wt, and it feels nearly as free as a broken in yokomo gear diff. The center oring appears to be doing a good job but the 5mm outdrive orings aren't. I'm seeing a trace of red losi shock oil on both ends. Does anyone think the shims I left out might help??