Product Introduction

The Rock Arm D12 is a heavy-duty engine rocker arm assembly designed for SINOTRUK D12 series diesel engines used in HOWO A7, SITRAK, and other heavy-duty commercial trucks. The rocker arm is an essential valve train component responsible for transferring camshaft motion to the intake and exhaust valves, ensuring precise valve timing and stable engine combustion performance.

During engine operation, the rocker arm converts the rotational movement of the camshaft into controlled linear valve motion, helping maintain proper intake and exhaust airflow within the combustion chamber. Stable rocker arm performance is critical for engine power output, fuel efficiency, compression stability, and long-term operational reliability.

Manufactured from high-strength forged alloy steel with precision heat treatment technology, the rocker arm provides excellent resistance to wear, fatigue stress, and high-temperature operating conditions commonly found in heavy-duty diesel engines. D12 engine valve systems commonly use reinforced rocker arm shaft and rocker arm seat structures for high-load commercial applications.

This rocker arm assembly is widely used in SINOTRUK D12 Euro-III engine platforms installed on HOWO A7 tractor trucks, dump trucks, and mining transport vehicles. OEM-standard machining ensures accurate installation dimensions and reliable compatibility with original cylinder head assemblies. Similar D12 rocker arm assemblies are also used in WP12 heavy-duty diesel engine valve train systems.

Each unit undergoes hardness testing, dimensional inspection, and fatigue durability verification before shipment to ensure dependable engine performance and long service life.

Technical Specifications

Vehicle Fitment

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Related Products Categories

Engine Parts System

Transmission & Drivetrain Parts

Chassis & Suspension Parts

Cabin & Body Parts