Sunsong 3405187 Power Steering Return Line Hose Assembly - Pipe To Cooler

OE-Style Return Hose for Toyota Sienna

The Sunsong 3405187 power steering return line hose assembly is built for low-pressure, high-temperature return-side service. It is a direct-fit replacement for the pipe-to-cooler routing on 2007-2010 Toyota Sienna models, with materials and construction selected to restore proper steering fluid flow.

• Fits 2007-2010 Toyota Sienna, pipe to cooler
• CSM hose material for return-line service
• Rated for a maximum working pressure of 250 psi
• Built for low-pressure, high-temperature operation
• End 1: beaded tube fitting, 11.6 mm
• End 2: ID hose fitting, 9.6 mm
• Part number 3405187 for easy identification

Built for Return-Line Performance

This Sunsong power steering return line hose assembly is engineered to match the original routing and connection style used on the Toyota Sienna power steering system. The hose uses CSM construction and is intended for the return side of the system, where fluid moves back from the cooler under lower pressure but elevated temperature. Sunsong 3405187 is a practical replacement when the original hose shows age-related wear, seepage, or heat damage.

The assembly is specified for 2007-2010 Toyota Sienna applications at the pipe-to-cooler position. It cross-references Four Seasons 55570 for the same application.

Common Problems This Part Can Address

• Power steering fluid seepage at the return hose
• Cracking or hardening from heat exposure
• Restricted fluid return caused by hose deterioration
• Noise or uneven steering feel related to fluid loss
• Corrosion-related failure in the steering hose routing

Installation Notes and Tips

Confirm the pipe-to-cooler routing before installation and compare the end fittings to the removed hose. Inspect nearby clamps, cooler connections, and mounting points for wear or contamination before reassembly. Properly route the hose away from heat sources and moving components, and verify there are no leaks after refilling and bleeding the power steering system.

Quality Assurance

Sunsong manufactures this return hose assembly to exceed original equipment performance standards for return-line service, with a 250 psi maximum working pressure and construction suited to demanding temperature conditions. The hose is built for accurate fitment on the specified Toyota Sienna applications.