Heavy-Duty Truck Transmission Gear – A core component of the transmission system in commercial vehicles, primarily used to transmit power and change gear ratios (to achieve shifting and speed variation).

1. Product Positioning & Application

• Applicable Models: Mainly matches transmissions in heavy-duty trucks from Sinotruk (Howo, SITRAK), Shaanxi Automobile (Delong, Aolong), FAW Jiefang (J6, J7), Foton Auman, and other brands. Also compatible with the transmission systems of other domestic heavy-duty trucks or commercial vehicles.

• Function: Through gear meshing, it transmits engine power to the transmission output shaft. By using different gear combinations (e.g., pairs of gears with different tooth counts), it achieves torque and speed conversion (e.g., high torque in low gear, high speed in high gear), ensuring power output and fuel efficiency under heavy loads and complex road conditions.

2. Appearance & Structural Features

• Material: Typically made of high-strength alloy steel (e.g., 20CrMnTi, 40CrNiMo, etc.), processed through forging, carburizing and quenching, and gear grinding. It offers high hardness, wear resistance, and fatigue strength, suitable for frequent shifting and high-load power transmission in heavy-duty truck transmissions.

• Structure:

  • The gears are cylindrical or conical in shape (the image shows cylindrical gears, likely used for parallel-axis transmission in the gearbox). The tooth profile is involute (ensuring smooth meshing and high transmission efficiency).

  • The gear has a splined bore or parallel keyway in the center (to mate with the transmission shaft for torque transfer). Some gears feature chamfers or relief grooves (for easier machining and assembly).

3. Manufacturing & Branding

• Production & Brand: These are original transmission gears, genuine OEM parts, compatible with Sinotruk vehicle models (e.g., Howo, SITRAK) and their corresponding transmission series (e.g., HW series, Sinotruk 12-speed/16-speed transmissions, etc.).

• Compatibility: Different transmission models (e.g., Sinotruk HW19712, HW25716) have varying gear tooth counts, modules, spline specifications, and center distances. Strict selection according to the transmission model is required to avoid installation errors that could lead to shifting difficulties, abnormal noise, or transmission failure.