Try to avoid spraying any solvents on the differential itself (as distinct from the final drive case), especially its clutch packs -- if you dissolve the lub off the clutch packs, you may end up with a limited slip which is very reluctant to slip at all, as I did in 1968 with my 64 1/2 Mustang convertible -- it was great in autocrosses forever after, but a bit embarassing on right angle turns downtown.