Overview
The ZF 4143.303.044 COVER is a critical sealing and protective component engineered for the HL 100 and HL 270 series transmissions. This OEM genuine part encloses the valve body and hydraulic control assembly, ensuring that internal fluid pressure is maintained and that contaminants are kept out of the transmission housing. As a precision-machined cover, it directly interfaces with the main casing to secure the internal components during high-torque operations. The SKU 4143.303.044 is specifically designed to match ZF’s original manufacturing tolerances, guaranteeing a perfect seal and long service life when paired with the correct GASKET and CAP SCREW hardware.
Symptoms of Failure
When the ZF 4143.303.044 COVER begins to degrade, operators often notice external oil seepage around the perimeter of the transmission casing. A common long-tail search query is “ZF HL 270 cover oil leak fix,” which points directly to this part. Another failure symptom includes erratic gear engagement or delayed shifting, as a compromised cover cannot maintain the necessary hydraulic pressure for clutch pack actuation. Additionally, you may observe visible corrosion or pitting on the cover surface, which can lead to debris entering the system and accelerating wear on internal components like the HOUSING.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 4143.303.044 |
| Material | Die-cast Aluminum Alloy |
| Weight | 1.2 kg (2.65 lbs) |
| Overall Length | 245 mm |
| Overall Width | 185 mm |
| Height | 45 mm |
| OEM Reference | ZF 4143.303.044 |
| Surface Finish | Anodized / Corrosion-Resistant Coating |
Compatibility
This COVER is a direct fit for the ZF HL 100 and HL 270 series transmissions, which are commonly used in heavy-duty industrial vehicles and marine applications. Based on its design and mounting pattern, the 4143.303.044 is also compatible with the WG180, WG200, and WG210 series transmissions that share the same hydraulic control architecture. For proper installation, it must be used with the corresponding HOUSING to ensure correct alignment of the valve body channels.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101016 | HOUSING | Main casing for gear and shaft assembly |
| 4143301039 | HOUSING | Secondary housing for valve body support |
| 0501318136 | GASKET | Seals the cover-to-housing interface |
| 0636101084 | CAP SCREW | Fastener for securing the cover |
| 0750108044 | PLUG | Closes unused ports in the housing |
| 0636302014 | SCREW PLUG | Threaded seal for drain/fill holes |
| 0634801057 | SEALING RING | Provides leak-proof joint under pressure |
| 0730365092 | TYPE PLATE | Identification label for transmission model |
| 4143201019 | VALVE INSERT | Regulates hydraulic flow within the valve body |
| 0634306198 | O-RING | Static seal for hydraulic passages |
