Overview
The ZF 4642.321.156 TUBE is a precision-engineered hydraulic fluid conduit specifically designed for the WG 150 series transmission. This OEM genuine part, identified by SKU 4642.321.156, serves as a critical pressure line within the valve body assembly, directing lubricating oil to the clutch packs and planetary gear sets. Manufactured to ZF’s exacting tolerances, this tube ensures consistent fluid flow under high thermal loads, directly supporting shift quality and torque transmission efficiency. When installed alongside the TRANSMISSION HOUSING (4642101109) and the TRANSMISSION HOUSING (4642301205), it completes the primary lubrication circuit for the WG150’s rotating assembly.
Symptoms of Failure
- External oil seepage at the tube-to-housing interface: A worn or cracked 4642.321.156 tube often causes visible fluid drips near the bell housing, leading to low transmission fluid levels and eventual overheating.
- Erratic gear engagement or delayed shifts: When this tube develops internal restrictions or pinhole leaks, hydraulic pressure drops, resulting in soft shifts or hesitation when moving from neutral to drive.
- Whining or groaning noise during acceleration: A compromised tube can introduce air into the hydraulic circuit, causing cavitation and audible whining from the pump area, particularly under load.
- Burning odor from transmission fluid: Insufficient lubrication due to a failing tube accelerates clutch wear, producing a distinct burnt smell and darkening of the ATF.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number (SKU) | 4642.321.156 |
| Material | Seamless drawn steel, zinc-nickel plated |
| Overall Length | 185 mm (estimated) |
| Outer Diameter | 12 mm |
| Wall Thickness | 1.5 mm |
| Weight | 0.12 kg |
| OEM Reference | ZF 4642.321.156 |
| Sealing Type | O-ring groove at both ends |
Compatibility
This genuine ZF tube is primarily engineered for the WG 150 Series transmission family. Based on its hydraulic routing design, it is also compatible with the following ZF models: WG 180, WG 200, and WG 250 (when used in off-highway and industrial applications). For proper fitment, always verify the tube’s orientation against the TYPE PLATE (0730365125) affixed to your transmission housing. The tube interfaces directly with the GROOVED STUD (0631311009) to secure its position within the valve body channel.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4642101109 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4642301205 | TRANSMISSION HOUSING | Secondary housing for clutch assembly |
| 0730365125 | TYPE PLATE | Identification tag with model/serial data |
| 0631311009 | GROOVED STUD | Locating pin for tube alignment |
| 4642301168 | SCREEN SHEET | Fine mesh filter for oil pickup |
| 4642301169 | SCREEN SHEET | Coarse mesh pre-filter for sump |
| 0636100621 | HEXAGON SCREW | Fastener for valve body retention |
| 4642301186 | SCREEN SHEET | Secondary filter for cooler return line |
| 4644106324 | SHIFT SYSTEM | Electro-hydraulic shift control unit |
| 4644306598 | PLATE | Clutch piston backing plate |
