ZF 0631.501.032 FITTED KEY | OEM Genuine Part

Overview

The ZF 0631.501.032 FITTED KEY (SKU: 0631.501.032) is a precision-machined OEM genuine part designed to secure rotating components within ZF heavy-duty transmissions. This fitted key acts as a positive-locking element, typically seated between a shaft and a gear or hub, preventing rotational slippage under extreme torque loads. In construction machinery transmissions, it is critical for maintaining the alignment of the INPUT and OUTPUT shafts. Without this key, the driveline cannot transfer power reliably. As an OEM genuine component, it ensures exact fitment and metallurgical consistency, eliminating the risk of premature failure associated with aftermarket substitutes.

Symptoms of Failure

• Transmission gear slipping under load: A worn or sheared fitted key allows the gear to rotate independently on the shaft, causing intermittent power loss during excavation or lifting operations.
• Abnormal metallic grinding noises: When the key degrades, the shaft and hub make metal-on-metal contact, producing a distinct grinding sound that worsens with throttle application.
• Vibration in the driveline: Loss of key engagement creates rotational imbalance, leading to noticeable vibration through the chassis, particularly when shifting between forward and reverse.
• Sudden loss of drive in one gear range: Complete key failure results in the gear freewheeling on the shaft, causing a total loss of power to the HOUSING assembly.

Technical Specifications

Compatibility

This fitted key is engineered for integration into ZF powershift transmissions commonly found in construction machinery. Based on its design profile, it is compatible with the following ZF models: WG180, WG200, WG210, and WG310. It is also used in select 4WG-200 and 6WG-250 series transmissions. For precise fitment verification, always cross-reference the part number against your transmission’s serial plate. This key is often replaced alongside the GK10LD gear kit to ensure complete driveline integrity.

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