Overview
The ZF 4642.321.157 TUBE is a precision-engineered hydraulic fluid conduit specifically designed for the WG 150 series transmission. This OEM genuine part channels pressurized oil to the clutch packs and valve body, ensuring consistent lubrication and shift actuation. As a critical component of the transmission’s internal oil circuit, the tube maintains proper flow dynamics under high-temperature and high-pressure conditions. The SKU 4642.321.157 is manufactured to ZF’s exacting tolerances, making it a direct replacement for worn or damaged units. It is often installed alongside the TRANSMISSION HOUSING (4642101109) and the TRANSMISSION HOUSING (4642301205), which house the tube within the main gearcase assembly.
Symptoms of Failure
- External oil leaks near the transmission bell housing: A cracked or corroded 4642.321.157 tube often causes visible fluid drips, leading to low oil levels and eventual gear slippage.
- Erratic or delayed gear engagement: When the tube becomes blocked or deformed, hydraulic pressure drops, resulting in harsh or slow shifting during acceleration.
- Overheating transmission fluid: A compromised tube restricts oil flow, causing the transmission to run hotter than normal and triggering warning lights on the dashboard.
- Whining or grinding noises from the gearbox: Insufficient lubrication due to a failing tube increases friction between rotating components, producing audible metallic sounds.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4642.321.157 |
| Product Type | Hydraulic Fluid Tube |
| Material | Steel with anti-corrosion coating |
| Length (approx.) | 210 mm |
| Outer Diameter | 12 mm |
| Wall Thickness | 1.5 mm |
| Weight | 0.18 kg |
| OEM Reference | ZF 4642.321.157 |
| Compatible Housing | 4642101109, 4642301205 |
| Associated Fasteners | 0636100621 HEXAGON SCREW |
Compatibility
This tube is engineered for the ZF WG 150 series, but its design also supports select models in the WG 180 and WG 200 families due to shared hydraulic architecture. It is a direct fit for transmissions using the TYPE PLATE (0730365125) and the GROOVED STUD (0631311009). Always verify the part number against your transmission’s serial plate before ordering. For complete assembly, pair this tube with the SHIFT SYSTEM (4644106324) and the PLATE (4644306598) to ensure proper oil routing.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4642101109 | TRANSMISSION HOUSING | Encloses the gear train and oil passages |
| 4642301205 | TRANSMISSION HOUSING | Secondary housing for valve body integration |
| 0730365125 | TYPE PLATE | Identification plate for transmission model |
| 0631311009 | GROOVED STUD | Secures housing components together |
| 4642301168 | SCREEN SHEET | Filters debris from hydraulic fluid |
| 4642301169 | SCREEN SHEET | Secondary filtration element |
| 0636100621 | HEXAGON SCREW | Fastens tube to housing |
| 4642301186 | SCREEN SHEET | Fine mesh filter for oil return line |
| 4644106324 | SHIFT SYSTEM | Controls gear selection hydraulics |
| 4644306598 | PLATE | Cover plate for shift mechanism access |
