I agree with Chad M regarding Permatex Right Stuff. When prepped properly, you don't even get seepage of oil or grease, let alone a drip. It is somewhat adhesive so I don't use it on things that you anticipate would need to come off, such as a valve cover. It would be perfect for the differential carrier. I have commented on this product before and surprised that few people seem to use it. It is OEM on Caterpillar oilpans and used without a gasket.
Kent


1937 Chevy 1/2 ton
1942 Chevy 1/2 ton
1947 Diamond T Model 509
1951 Chevy 1/2 ton
1950 Chevy COE Model 5700 ~ "Barney" ~ And more pix