ZF 5838.300.042 SPUR GEAR for WG100/WG130/WG131 | OEM Genuine Part

Overview

The ZF 5838.300.042 SPUR GEAR is a precision-machined component engineered for the auxiliary drive and power take-off (PTO) circuits within ZF WG100, WG130, and WG131 transmission assemblies. This OEM genuine gear transfers rotational force from the input shaft to the differential housing, ensuring synchronized torque distribution under heavy loads. The SKU 5838.300.042 is manufactured to ZF’s original tolerances, featuring hardened tooth profiles that resist pitting and wear in continuous-duty applications. When installed alongside a 5838109007: DIFFERENTIAL, this spur gear maintains backlash consistency critical for smooth gear engagement.

Symptoms of Failure

• Whining or howling noise during deceleration: Worn tooth flanks on the 5838.300.042 spur gear create a high-pitched metallic sound, especially when the transmission is under load in WG100 models.
• Intermittent PTO engagement failure: Excessive backlash from a damaged spur gear prevents the PTO clutch from locking, causing intermittent power loss to auxiliary equipment.
• Metallic debris in transmission fluid: Flaking or chipped gear teeth shed ferrous particles into the oil, often visible during routine drain intervals. This debris can accelerate wear on the 0750117075: TAPER ROLLER BEARING supporting the gear shaft.
• Vibration at highway speeds: A cracked or unevenly worn spur gear induces driveline vibration that intensifies above 45 mph, often misdiagnosed as a failing 2095209019: DIFFERENTIAL.

Technical Specifications

Compatibility

This spur gear is specifically designed for ZF WG100, WG130, and WG131 series transmissions used in medium-duty trucks, buses, and agricultural machinery. It is a direct replacement for the original gear in the auxiliary drive train. While the WG180 and WG200 models share similar gear architecture, the 5838.300.042 is not cross-compatible due to differing shaft diameters and tooth counts. Always verify your transmission model code before ordering. For differential-side applications, the 0631329086: SPRING PIN is required to secure the gear to the output shaft.

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