Mercury - High Performance Extreme Grease Multi-Purpose Marine Lubricant 14 oz Cartridge 8M0190472. Overview. Every seasoned boater has a few go-to products they trust without hesitation, and this is one of them. Mercury's High Performance Extreme Grease, part number 8M0190472, brings that calm reassurance you feel when every moving part on your boat behaves exactly the way it should. You know the feeling - the wheel turns without a hint of drag, the shift cable glides into gear, and nothing gri