Overview
The ZF 4644.121.435 OIL PIPE is a precision-engineered fluid conduit designed specifically for the WG 200 series transmissions. This OEM genuine part ensures consistent lubrication and hydraulic pressure delivery to critical internal components, including the clutch packs and valve body. Positioned within the transmission’s oil circuit, the 4644.121.435 pipe channels ATF to reduce friction and heat buildup during high-torque operations. As a direct replacement for worn or damaged lines, this SKU guarantees factory-specified flow rates and pressure integrity, preventing contamination from debris ingress. When paired with a properly sealed 4644105414: DISCONNECTION assembly, the oil pipe maintains system reliability under heavy-duty cycles.
Symptoms of Failure
- External oil leaks near the transmission pan or bell housing: Cracks or corrosion in the 4644.121.435 pipe often cause visible fluid drips, especially after thermal cycling. This is a common search query for “ZF WG200 oil pipe leak symptoms.”
- Delayed or harsh gear engagement: Insufficient hydraulic pressure from a compromised oil pipe leads to slipping between shifts, particularly in 2nd-to-3rd gear transitions.
- Overheating transmission fluid: A restricted or collapsed pipe reduces oil flow, causing elevated operating temperatures that trigger warning lights or burnt fluid odor.
- Whining or groaning noises from the transmission: Air entrainment from a cracked pipe creates cavitation sounds, often misdiagnosed as pump failure.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4644.121.435 |
| Material | Seamless steel tube with zinc-nickel coating |
| Length | 215 mm (estimated) |
| Outer Diameter | 12 mm |
| Wall Thickness | 1.5 mm |
| Weight | 0.18 kg |
| OEM Reference | ZF 4644.121.435 |
| Thread Type | M14 x 1.5 (both ends) |
Compatibility
This oil pipe is engineered for the ZF WG 200 series, including models such as WG180, WG200, and WG210. It is also compatible with certain off-highway variants like the WG 150 and WG 250 when used in conjunction with the correct 4644303409: OUTPUT FLANGE and 4644101222: TRANSMISSION HOUSING. Always verify fitment by cross-referencing your transmission’s serial number. For secure mounting, use a 0636021083: HEXAGON SCREW to fasten the pipe bracket to the housing.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644105414 | DISCONNECTION | Separates oil lines for service access |
| 4644303409 | OUTPUT FLANGE | Connects driveshaft to transmission output |
| 0636021083 | HEXAGON SCREW | Secures pipe brackets and covers |
| 4644101222 | TRANSMISSION HOUSING | Main structural casing for gear sets |
| 4644301226 | TRANSMISSION HOUSING | Alternate housing variant for WG200 |
| 0730365067 | TYPE PLATE | Identification tag with transmission specs |
| 0631311009 | GROOVED STUD | Locates and aligns housing components |
| 4644301298 | COVER PLATE | Seals access opening in transmission |
| 0634306525 | O-RING | Prevents fluid leaks at pipe connections |
| 0636305026 | SCREW PLUG | Closes unused ports in the housing |
