Description

The Cummins 6.7 ISB Steel Crown Piston M-8619 (Standard Size) is a heavy-duty piston assembly engineered specifically for 6.7L ISB Chrysler applications , where high combustion pressure, elevated exhaust gas temperatures, and continuous-duty operation demand superior piston strength. This piston is a direct replacement for OE part numbers 5258754 and 5258755 , delivering OEM-correct fitment and long-term reliability in Cummins diesel engines . Steel crown pistons are designed to outperform conventional aluminum pistons in modern common-rail diesel engines. The steel crown construction significantly improves resistance to thermal fatigue, cracking, and crown deformation while supporting higher cylinder pressures common in turbocharged 6.7 ISB platforms used in Chrysler/RAM applications. The M-8619 piston features precision-machined ring lands, controlled thermal expansion geometry, and an optimized skirt profile to reduce friction and maintain piston stability. When paired with the correct piston ring set, pin, and retainers, it helps restore factory compression, minimize blow-by, and control oil consumption. This piston is commonly installed during 6.7 ISB engine rebuilds, in-frame overhauls, piston replacements, and professional remanufacturing projects . It is trusted by diesel engine builders, fleet operators, and performance-focused repair facilities seeking OEM-level durability. Cross-Reference (OEM) Aftermarket Reference: M-8619 OEM References: 5258754, 5258755 Engine: 6.7L ISB Application: Chrysler / RAM Size: Standard (STD) Type: Steel Crown Piston