I took my mercedes to a tire shop that i have been going to for about 20 years, I about fell over when i looked at the bill. Ok I had them pull the rear cover off of the diff because of a Leak, seems like all those covers leak. any way resealed cover with sylicone or how ever it is spelled, put in new rear end oil done. ok look at the bill and they charged me for Oil and labor and $3.50 for sylicone, I bet he didnt use 1/8 of it out of the tube. boy it they charge everyone that much every time they use that stuff they could buy 400 tubes a week...