Mobil SHC 634 (ISO 460) synthetic gear oil is the ultimate worm drive gearbox lubricant. SHC 634 will greatly extend worm gearbox life. The gearbox will run cooler, easier, with reduced power loss. Sold in 5 gallon pails. Mobil SHC 634 Synthetic Gear Oil 5 GAL PAIL 98R938Regular price: $278.30Sale price: $258.90 © 2004 AVLubricants - ExxonMobil Distributor Specializing In Hard To Find Products