Overview
The ZF 0631.100.273 GROOVED PIN is a precision-engineered locating and alignment component designed for the internal assembly of ZF WG100, WG130, and WG131 transmissions. This OEM genuine part ensures correct positional registration between the transmission housing and cover assemblies, preventing rotational misalignment under high-torque loads. The SKU 0631.100.273 is manufactured to exact ZF tolerances, featuring a machined groove that facilitates secure retention within the bore. This pin is critical for maintaining the concentricity of the gear train and preventing axial shift during operation. It is frequently replaced during a full transmission rebuild alongside the 4699101124: HOUSING and the 4699301209: HOUSING to restore factory-clearance specifications.
Symptoms of Failure
- Transmission housing misalignment and gear whine: A worn or sheared grooved pin allows the housing halves to shift, producing a distinct high-pitched whine during acceleration as gear mesh patterns become irregular.
- Recurring oil seepage at the housing split line: When the pin fails to maintain alignment, the seal between the 4699301015: HOUSING COVER and the main housing can be compromised, leading to slow oil weeping that worsens with thermal cycling.
- Hard shifting or gear engagement delay: Misalignment caused by a degraded pin can bind the shift rails or valve body linkage, resulting in delayed engagement when moving from neutral to drive or reverse.
- Abnormal vibration at the bell housing: A broken grooved pin permits micro-movement between the transmission case and the 4699301085: COVER, transmitting vibration through the driveline that is felt in the chassis at highway speeds.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number (SKU) | 0631.100.273 |
| Product Type | Grooved Pin (Dowel Pin) |
| Material | Case-hardened alloy steel (estimated 60-62 HRC) |
| Overall Length | 28.0 mm (estimated) |
| Outer Diameter | 10.0 mm (estimated) |
| Groove Width | 2.5 mm (estimated) |
| Weight | Approx. 17 grams |
| OEM Reference | ZF 0631.100.273 |
| Fitment Type | Interference fit with retention groove |
Compatibility
This OEM genuine grooved pin is specifically engineered for the ZF WG100, WG130, and WG131 series transmissions. It is also utilized in select WG180 and WG200 variants that share the same housing architecture. The pin serves as a dowel for the main housing and cover interface. When servicing these units, always inspect the mating bores in the 4699101124: HOUSING for wear. For complete assembly integrity, pair this pin with a new 0634303980: O-RING on the cover seal and a 0501329618: VENT VALVE to ensure proper case pressure regulation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4699101124 | HOUSING | Main transmission case casting |
| 4699301209 | HOUSING | Rear housing section |
| 4699301015 | HOUSING COVER | Front or side cover plate |
| 4699301085 | COVER | Access cover for valve body |
| 4699301014 | THREAD PROTECTIVE SHIELD | Protects threads during assembly |
| 0634303980 | O-RING | Seals housing-to-cover interface |
| 0734307425 | PROTECTION CAP | Covers exposed ports during storage |
| 0501329618 | VENT VALVE | Regulates internal case pressure |
| 0636102023 | CAP SCREW | M10 fastener for housing bolts |
| 0636101008 | CAP SCREW | M8 fastener for cover attachment |
