MAHLE 930036075T Piston Kit with TBC (407cid 4.075 x 1.951CH, 3.898stroke, 6.417rod, 1.358pin, -40.7cc, 880g, 16.8CR, M142) for GM 6.6L DuramaxGM 6. 6L Duramax Cast Performance Pistons Revised casting with improved crown geometry and performance bowl design, coated skirt Ring Set (40xxMDK D) Included CH reduced 0. 010" Fits LB7, LLY, LBZ, LMM, LGH, LML CR calculated with 0. 012" piston protrusion above deck and 0. 037 x 4. 115" head gasket Performance Cast Designed for street strip or pulling trucks making 400 1000Hp that still get used as a daily driver or work truck. Machined from OE