Overview
The ZF 4657.199.401 LOOSE PARTS kit is a critical OEM genuine service set designed specifically for the WG210 series transmission. This assembly group contains the essential fasteners, seals, and positioning elements required to secure internal components during a rebuild or overhaul. Positioned within the main gearcase cavity, this kit interfaces directly with the TRANSMISSION HOUSING, the HOUS.FRONT SECT, and the HOUSING REAR PART to maintain precise alignment and clamping force. The SKU 4657.199.401 is a genuine ZF factory part, ensuring metallurgical consistency and thread tolerances that aftermarket substitutes often fail to match.
Symptoms of Failure
- Transmission oil seepage at housing joints: When the loose parts (bolts, pins, or sealing washers) degrade, the clamping load between the CYLINDRICAL PIN and housing flanges diminishes, leading to visible oil weeping around the WG210 split lines.
- Intermittent gear engagement hesitation: Worn or missing fasteners allow micro-movement of the front and rear housing sections, causing misalignment of the clutch drum and planetary gear sets. This results in delayed or rough shifts under load.
- Abnormal vibration during torque converter lockup: Loose housing bolts permit flex in the transmission case, transmitting harmonic vibrations through the driveline that are most noticeable at highway speeds.
- Increased metallic debris in the oil pan: Fretting corrosion from loose mating surfaces generates fine steel particles that bypass the SCREEN SHEET and contaminate the hydraulic control system.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4657.199.401 |
| OEM Reference | ZF 4657.199.401 |
| Material Composition | Case-hardened alloy steel (fasteners); Nitrile rubber (seals) |
| Weight (kit) | 0.85 kg (1.87 lbs) |
| Thread Pitch | M10 x 1.5 (primary bolts) |
| Torque Specification | 45 Nm ± 3 Nm (dry) |
| Operating Temperature Range | -40°C to +120°C |
| Compatible Fasteners | CAP SCREW (0636100801) and CAP SCREW (0636100803) |
| Associated Plates | FIXING PLATE (4656301148) |
Compatibility
This LOOSE PARTS kit is engineered for the ZF WG210 series but shares dimensional interfaces with the WG180 and WG200 families due to common housing architecture. It is directly compatible with transmissions using the OIL FEED.HOUSG. (4681301040) and the dual SCREEN SHEET (4657301035) filtration setup. Always verify housing casting numbers before installation, as late-model WG210 units may use revised bolt patterns.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101039 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4657201028 | HOUS.FRONT SECT | Front section housing for pump and clutch |
| 4657201013 | HOUSING REAR PART | Rear section housing for output shaft |
| 0631306792 | CYLINDRICAL PIN | Alignment dowel for housing mating |
| 0636100801 | CAP SCREW | M10 bolt for housing fastening |
| 4656301148 | FIXING PLATE | Retention plate for bearing preload |
| 4657301034 | SCREEN SHEET | Fine mesh filter for oil circuit |
| 4657301035 | SCREEN SHEET | Secondary mesh filter for valve body |
| 0636100803 | CAP SCREW | M8 bolt for accessory mounting |
| 4681301040 | OIL FEED.HOUSG. | Pressurized oil supply housing |
