Overview
The ZF 4472.374.156 轴承销, an OEM genuine part, functions as a precision-machined bearing pin within the planetary gearset assembly of heavy-duty construction machinery transmissions. This component serves as a stationary axle for needle bearings and thrust washers, ensuring correct gear alignment and load distribution under extreme torque. The SKU 4472.374.156 is a direct replacement for the original factory pin, engineered to maintain the exact clearance tolerances required for smooth planetary rotation. Without this pin, the bearing cage loses its structural anchor, leading to catastrophic gear train misalignment.
Symptoms of Failure
When the ZF 4472.374.156 bearing pin wears beyond specification, operators will notice distinct mechanical distress signals. Intermittent gear slipping under load is a primary indicator, as the pin’s surface wear allows the planetary gears to shift axially. Metallic grinding noises from the transmission housing during low-speed operation often point to the pin’s hardened surface being compromised. Increased backlash in the driveline—a clunking sensation when shifting between forward and reverse—occurs as the pin’s diameter reduces from fretting corrosion. Finally, contaminated transmission oil with bronze or steel particles in the filter indicates the pin is shedding material into the lubrication system.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number (SKU) | 4472.374.156 |
| Material | Case-hardened alloy steel (16MnCr5 equivalent) |
| Surface Hardness | 58–62 HRC |
| Outer Diameter | 25.00 mm ± 0.013 mm |
| Overall Length | 68.50 mm ± 0.10 mm |
| Weight | 0.34 kg (0.75 lbs) |
| OEM Reference | ZF 4472.374.156 (Genuine) |
| Thread Specification | M8 x 1.25 internal (both ends) |
Compatibility
This bearing pin is engineered for ZF’s heavy-duty powershift transmission series commonly deployed in construction loaders, graders, and dozers. Primary compatible models include the WG180, WG200, and WG210 series, where it serves as the sun gear carrier pivot pin. It also fits the 4WG-200 and 6WG-200 variants used in articulated dump trucks. For the ZF Ergopower 3 (Ecomix) series used in concrete mixers, this pin is a direct drop-in replacement for the planetary reduction stage. Always verify the pin’s length against your existing carrier bore depth before installation.
Installation Notes
- Inspect the carrier bore for ovality using a bore gauge before pressing the new pin.
- Apply a thin film of ZF-approved assembly lubricant to the pin’s outer diameter.
- Torque retaining bolts to 45 Nm using a calibrated wrench.
