Overview
The ZF 4651.199.040 LOOSE PARTS kit is a critical service component designed specifically for the WG 100 series transmission. This genuine OEM assembly contains the essential fasteners, seals, and small hardware required to secure and seal the transmission housing during a rebuild or major repair. Positioned at the interface between the main casing and the valve body, this kit ensures that the TRANSMISSION HOUSING maintains structural integrity under high torque loads. The SKU 4651.199.040 is factory-matched to ZF’s exact tolerances, eliminating the guesswork of sourcing individual bolts and washers. Without this specific loose parts set, technicians risk improper clamping forces that can lead to fluid migration or gear misalignment.
Symptoms of Failure
- Transmission fluid seepage at housing seams: When the 4651.199.040 hardware fatigues or corrodes, the clamping force on the O-RING seal diminishes, causing visible oil weeping around the joint between the main housing and the HOUSING.
- Intermittent gear slippage under load: Loose fasteners from a degraded loose parts kit allow the valve body to shift slightly, disrupting hydraulic pressure to clutch packs. This often manifests as hesitation when shifting from 2nd to 3rd gear.
- Abnormal driveline vibration: A compromised 4651.199.040 set can cause the HOUSING to flex, introducing micro-movements that transmit vibration through the driveline at highway speeds.
- Increased operating temperature: Internal fluid bypass due to improper sealing from worn loose parts forces the transmission to work harder, raising sump temperatures by 15-20°F above normal.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4651.199.040 |
| OEM Reference | ZF 4651.199.040 |
| Material Composition | Steel (fasteners), Nitrile (seals), Zinc-plated hardware |
| Weight | 0.85 kg (1.87 lbs) |
| Kit Contents | Bolts, washers, dowel pins, and sealing elements |
| Torque Specification | 45 Nm ± 5 Nm (housing bolts) |
| Operating Temperature Range | -40°C to +120°C |
Compatibility
This genuine ZF 4651.199.040 loose parts kit is engineered for the WG 100 series transmission family. It is directly compatible with the following models: WG100, WG120, WG150, WG180, and WG200. The kit also applies to select variants of the WG 100 Series used in off-highway and industrial equipment. Always verify the housing casting number before installation, as the TRANSMISSION HOUSING design changed slightly after serial number 2,500,000. For earlier housings, cross-reference with the HOUSING part number to confirm fitment.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4651101007 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4651301029 | HOUSING | Secondary housing for valve body assembly |
| 0634303928 | O-RING | Static seal between housing sections |
| 4651301024 | HOUSING | Rear housing for output shaft support |
| 4651203002 | SCREEN SHEET | Filter mesh for hydraulic fluid |
| 4651303005 | SCREEN SHEET | Secondary filter element |
| 0636101032 | CAP SCREW | Fastener for housing attachment |
| 0630361028 | SEALING CAP | Port closure for test points |
| 4475280060 | SCREW PLUG | Threaded plug for drain/fill ports |
| 0634303312 | O-RING | Seal for screw plug interface |
