ZF 4651.221.021 TUBE for WG100 | OEM Genuine Part

Overview

The ZF 4651.221.021 TUBE for WG100 is a precision-engineered fluid conduit designed to direct pressurized oil within the valve body and clutch pack assembly of the WG 100 Series transmission. This OEM genuine part, identified by SKU 4651.221.021, ensures correct flow dynamics for shift timing and torque converter lock-up. It is mounted directly between the TRANSMISSION HOUSING and the upper valve body, where it seals against the HOUSING to maintain consistent hydraulic pressure. Without this tube, the transmission cannot achieve proper gear engagement.

Symptoms of Failure

• Hydraulic fluid seepage at the valve body interface – A cracked or corroded 4651.221.021 tube allows ATF to weep past the O-RING, leaving visible drips on the bell housing.
• Erratic shift hesitation under load – When the tube deforms, oil pressure drops to the clutch packs, causing delayed upshifts or slipping in third and fourth gears.
• Low line pressure warning codes – Internal leakage through a worn tube triggers diagnostic trouble codes (e.g., P0741) as the transmission control module detects insufficient pressure.
• Contaminated fluid from debris ingress – A fractured tube can allow particles to enter the oil gallery, accelerating wear on the HOUSING and valve spools.

Technical Specifications

Compatibility

This tube is engineered for the ZF WG 100 Series, including models WG100, WG120, and WG150. It is also compatible with select WG180 and WG200 variants that share the same valve body architecture. Always verify fitment against your transmission’s serial number. For the WG200, the HOUSING may require a different tube length; cross-reference with the 4651.221.021 before installation.

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