ZF 4651.321.008 TUBE for WG100 | OEM Genuine Part

Overview

The ZF 4651.321.008 TUBE for WG100 is a precision-engineered fluid conduit designed to direct pressurized transmission oil within the valve body and clutch housing assembly. As an OEM genuine part, this tube ensures correct flow dynamics for lubrication and shift actuation in the WG 100 series. The SKU 4651.321.008 sits between the main control unit and the rotating drum, acting as a critical link in the hydraulic circuit. When replacing this component, it is common to also inspect the TRANSMISSION HOUSING for cracks or wear, as both parts share the same oil gallery interface.

Symptoms of Failure

• External oil seepage at the tube-to-housing joint – A worn 4651.321.008 tube can cause visible fluid drips under the transmission bell housing, often mistaken for a main seal leak.
• Delayed or harsh gear engagement – When the tube develops internal cracks or corrosion, hydraulic pressure drops, leading to sluggish shifts or clutch slip during acceleration.
• Low transmission fluid level without visible pan leaks – A fractured tube can allow oil to bypass into the bell housing cavity, causing unexplained fluid loss and eventual overheating.
• Whining or buzzing noise from the transmission sump – Air entrainment from a loose or damaged tube creates cavitation noise, particularly in the WG100 under heavy load.

Technical Specifications

Compatibility

This tube is engineered specifically for the ZF WG100 series transmission, but it also fits select variants in the WG180 and WG200 families where the hydraulic tube routing is identical. Always verify the part number against your transmission’s serial plate. The 4651.321.008 tube interfaces directly with the HOUSING (4651301025) and the HOUSING (4651301031) in the valve body section. For complete hydraulic integrity, ensure the mating O-rings are replaced simultaneously.

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