MAHLE 42246 Moly Piston Ring Set - Navistar MaxForce 7 2011-Up

The MAHLE 42246 is a plasma-moly piston ring set engineered specifically for the Navistar MaxForce 7 diesel engine (2011 and up). As a direct OE-replacement ring set, it is manufactured to exact OE form, fit, and function standards, delivering the reliability and precision today's diesel engine rebuilders demand.

Ring Construction & Materials:

• Upper Compression Ring (UCR): Carbon steel with plasma-moly face coating — axial height 1.2mm, RF-13PFD ring type
• Lower Compression Ring (LCR): High-quality cast iron (THM-10 napier design) — axial height 1.5mm
• Oil Control Ring (OCR): Stainless steel with chrome facing — CP-20 design, axial height 2.5mm

Key Features:

• SAE 9254 high alloy steel base material for superior tensile and yield strength, extended fatigue resistance, and increased hardness
• Plasma-moly top ring coating reduces friction and promotes rapid, even seating
• Pre-lapped design virtually eliminates break-in time for immediate seating
• CNC-controlled gap chamfer on compression rings optimizes sealing and reduces blowby
• CP-20 oil control ring assembly features an exclusive 20-degree ear angle for maximum side seal in the piston oil ring groove
• Second ring napier profile provides superior oil control and improved combustion gas management
• Available in STD, .010, .020, .030, and .040 inch oversizes for precise bore fitment

MAHLE is one of the largest OE piston ring manufacturers in the world. The MAHLE 42246 ring set is engineered to minimize engine oil consumption, reduce internal friction, and deliver extended service life — making it the professional choice for MaxForce 7 diesel engine overhauls and rebuilds.