Description

The Cummins Steel Crown Piston M-3164-50 (0.50 mm Oversize) is a heavy-duty piston assembly engineered for diesel engines that have undergone cylinder boring during professional rebuilds. Designed as a direct replacement for OE part number 3802407 , this piston delivers OEM-correct fitment, restored compression, and long-term durability in Cummins diesel engines . Steel crown pistons are purpose-built to handle higher combustion pressures and elevated operating temperatures than conventional aluminum pistons. The steel crown construction improves resistance to thermal fatigue and crown deformation, making this piston ideal for high-load and continuous-duty applications. The 0.50 mm oversize (OS) specification compensates for material removed during cylinder machining, ensuring proper piston-to-wall clearance and stable combustion geometry. Precision-machined ring lands, controlled thermal expansion characteristics, and an optimized skirt profile help reduce friction, maintain piston stability, and extend engine service life. The M-3164-50 steel crown piston is commonly installed during engine rebuilds, in-frame overhauls, and professional remanufacturing projects where cylinders have been bored 0.50 mm oversize. When paired with the correct oversize ring set, piston pin, bushings, and retainers, it helps restore factory performance and reliability. Cross-Reference (OEM) Aftermarket Reference: M-3164-50 OEM Reference: 3802407 Size: 0.50 mm Oversize Type: Steel Crown Piston