Why bypass filtration? Isn't the "spin-on" filter that comes on a truck good enough? That's what the manufacturers provide, right? We want bypass filtration because the OEMs do everything that's needed to be "good enough." Good enough to outlast the competition a few years longer. Good enough to provide the customer with a truck that will meet his needs while keeping the bottom line low enough to sell the truck to the general public. We all know this is the case with so many aspects of the OEM product that comes on our trucks.
The oil filter on diesel pickups has a challenge at hand. It has to filter all of the oil that gets pumped through the engine and remove enough particles and contaminants from the oil to keep engine wear to a minimum. At the same time, it has to move a lot of oil. The engine needs at least 30 to 40 gallons of oil to flow through the filter per minute in order to keep everything lubricated and moving.
The best a spin-on filter can do while keeping both sides of the deal is to filter everything from large particulates down to anything as small as 25 microns.