Description

The Cummins Aluminum Piston Assembly M-0187-50 (0.50 mm Oversize) is a precision-engineered replacement piston designed for diesel engines that have been lightly bored during professional rebuilds. This piston assembly directly replaces Cummins OE part number 3802237 , delivering OEM-accurate fitment, correct compression height, and reliable combustion performance. Engineered for Cummins diesel engines , the high-strength aluminum alloy construction provides excellent heat dissipation, reduced reciprocating weight, and smooth engine operation. Aluminum pistons are ideal for standard- and medium-duty applications where balanced thermal expansion, efficiency, and dependable longevity are required. The 0.50 mm oversize specification restores proper piston-to-cylinder clearance in bored cylinders, helping maintain compression and oil control. Precision-machined ring lands and an optimized skirt profile reduce friction, minimize piston slap, and support long service life under continuous operating conditions. This piston assembly is commonly installed during in-frame overhauls, full engine rebuilds, and professional reconditioning projects . It is trusted by diesel technicians, fleet maintenance teams, and engine builders seeking OEM-style performance and reliability.