ZF 4661.221.003 SUCTION TUBE for WG94 | OEM Genuine Part

Overview

The ZF 4661.221.003 SUCTION TUBE is a critical hydraulic component engineered specifically for the WG 94 Series transmission family. This OEM genuine part serves as the primary conduit for drawing transmission fluid from the sump to the pump, ensuring consistent lubrication and cooling under heavy load conditions. Positioned within the lower valve body assembly, the SKU 4661.221.003 maintains proper fluid flow dynamics, preventing cavitation and protecting internal gears. When paired with a functioning 6073003011: CONTROL UNIT, this suction tube guarantees stable hydraulic pressure across all operating ranges.

Symptoms of Failure

• Intermittent gear slipping under load: A cracked or warped suction tube allows air ingress, causing hydraulic pressure drops that manifest as hesitation or slipping during acceleration.
• Low fluid level warnings with no external leaks: Internal fractures in the tube can cause fluid to bypass the pump, triggering dashboard alerts even when the sump appears full.
• Whining or cavitation noise from the transmission: When the suction tube collapses or becomes blocked, the pump struggles to draw fluid, producing a distinct high-pitched whine that worsens at higher RPMs.
• Erratic shift timing: Inconsistent fluid delivery to the 6073003011: CONTROL UNIT results in delayed or harsh shifts, particularly during cold starts.

Technical Specifications

Compatibility

This suction tube is designed for the ZF WG 94 Series, but its hydraulic geometry also supports several related models. Verified compatibility includes the WG94, WG180, and WG200 transmissions used in heavy-duty construction and agricultural equipment. The part interfaces directly with the 4661101033: HOUSING and 4661301096: HOUSING assemblies, making it a direct replacement for units built between 2015 and 2023. Always verify the 4656183200: LOOSE PARTS kit for any additional sealing components required during installation.

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