I just had the fluids in the front and rear diffs changed by the dealer... wow! I don't know if all the diffs use the same lube, but what they put in my diffs (limited slip) came to $134 JUST FOR THE LUBE! (7 quarts at almost $20/qt) Add $111 for labor time and that's one stiff bill. Holy smokes... I need a shade tree and a creeper...