I don't use gaskets for the diff covers either. And as stated.... use a gear oil that has the additive in it. I use Lucas 85-140 in both diffs. My rear is a trak loc and front is open....
~Todd~ 2004 X 4.0 5 speed---SOLD
4" Lift, 4.56's, 33" Duratracs on M/T Classics
RR SYE, Tatton CV, MML, BL, TT, Dynomax Exhaust
Hella Lighting: Driving, Fogs and H4 E-Codes
... and NEVER will be