Replacement Shaft - SBM Rocker Arm

The Replacement Shaft - SBM Rocker Arm from MELLING (MRS-641) is an OEM-quality rocker arm shaft engineered for small block Mopar engines. This critical internal component maintains precise valve timing and lift by serving as the pivot point for rocker arms in your engine's valve train assembly. Whether you're rebuilding a classic Mopar engine, restoring a muscle car, or maintaining a daily driver, this shaft is essential for reliable valve actuation and engine performance.

Manufactured from durable steel, this rocker arm shaft is designed to withstand the continuous mechanical stress of valve train operation under load. The shaft's precision-engineered diameter and length (18.35 inches) ensure proper fitment and alignment of rocker arms, maintaining correct valve clearance and preventing excessive wear on cam followers and valve stems. MELLING's engineering expertise guarantees that this replacement meets or exceeds original equipment specifications for material hardness, surface finish, and dimensional tolerance, critical factors that directly impact engine efficiency and longevity.

This shaft is ideal for small block Mopar engines including 318, 340, and 360 cubic inch variants commonly found in Dodge, Plymouth, and Chrysler vehicles from the 1960s through 1990s. Installation requires removing the valve cover and rocker arm assembly, then carefully sliding out the worn shaft and installing the new replacement. Proper rocker arm shaft maintenance prevents catastrophic valve train failure, abnormal valve timing, and potential engine damage. Sourcing OEM-equivalent components ensures your Mopar engine runs smoothly and reliably for years to come.