If you are running one of the Driven Diesel Transmission Cooler Kits, you have already discovered how well it works. Due to demand from customers that live in cold climates that wanted to see their transmission warm up more in the winter, Driven Diesel also came up with this quick bypass kit to cleanly address the need. This kit takes about 5-10 minutes to install, and about the same amount of time to swap back to using the standard cooler when the ambient temps go back up. It also ensures that the cooler and lines will not get contaminated when they are not in use.