The stock oil cooler on the E46 M3 is simply not up to the task. We have solved that problem by assembling this kit that consists of a much bigger capacity Fluidyne oil cooler, the TMS Oil Line Cooler Kit and the TMS Oil Line Fitting Kit. The Fluidyne oil cooler fits into the factory location (brackets must be made) and offers much better cooling. All of these components connect together using AN-10 fittings.