ZF 4008.305.002 ANTI-FATIGUE BOLT | OEM Genuine Part

Overview

The ZF 4008.305.002 ANTI-FATIGUE BOLT is a precision-engineered OEM genuine fastener designed to secure critical internal assemblies within ZF construction machinery transmissions. This bolt mitigates cyclic stress loads that occur during high-torque gear shifts, preventing loosening and maintaining clamping force over extended service intervals. Positioned within the main gear train housing, it anchors components such as the clutch pack and planetary gear sets. The SKU 4008.305.002 is manufactured to ZF’s exacting tolerances, ensuring a direct replacement that restores original transmission integrity without modification.

Symptoms of Failure

• Transmission oil seepage at bolt interface: When the anti-fatigue bolt loses its preload, micro-gaps form between the 2094101012 TRANSMISSION HOUSING and mating surfaces, allowing ATF to weep out during operation.
• Intermittent gear slippage under load: A fatigued bolt permits slight movement of internal components, causing delayed or incomplete clutch engagement that manifests as power loss during acceleration.
• Metallic rattling from transmission bell housing: Loose clamping allows planetary gears to shift axially, producing a distinct chatter that worsens in lower gears.
• Increased vibration at steady highway speeds: Worn bolts fail to dampen harmonic resonance, transferring excessive vibration through the driveline to the chassis.

Technical Specifications

Compatibility

This anti-fatigue bolt is engineered for ZF’s heavy-duty powershift transmission series commonly deployed in construction machinery. Verified compatible models include the WG180, WG200, WG210, and WG250 series. It also applies to select 4WG-200 and 6WG-250 variants used in wheel loaders and graders. When replacing this bolt, always inspect the mating 2094301036 HOUSING for thread damage and verify the 2094298057 HOUSING alignment. The 2094301071 COVER should be removed to access the bolt location during service.

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