Mercury - Quicksilver 8M0175742 V-Twin Primary Chaincase & Transmission Fluid High-Performance Lubricant Petroleum Synthetic Blend 8M0175742. Overview. If you've spent enough time riding, you know your V-twin has a personality of its own - the thrum, the pull, the way it settles into a rhythm when everything's working the way it should. A transmission that shifts smoothly isn't just a convenience; it's part of what makes the ride feel connected and controlled. With Quicksilver's V-Twin Primary C