Rein CHE0523 Engine Coolant Hose - Expansion Tank (Upper) To Cylinder Heads

OE Quality Coolant Hose for BMW V8 Cooling Systems

Rein CHE0523 is an OE quality engine coolant hose built for European vehicle cooling systems that need an exact-fit replacement. It is designed for BMW 545i, 645Ci, 550i, and 650i applications with the correct branch shape and thermoplastic quick connect fitting layout for a direct service replacement.

• Direct replacement for OE hose and hose assembly applications
• Reduces installation time with application-specific fitment
• No cutting, refitting, or adjusting the hose during installation
• Helps prevent leaks and repeat repairs from reused quick connectors and O-rings
• EPDM hose construction resists heat, salt, road debris, oil, and other contaminants
• Single-hose design with one branch and one quick connect fitting
• Built to SAE J20R4D1 standards

Detailed Product Overview

Rein CHE0523 is a black EPDM engine coolant hose engineered as a direct OE-style replacement for the expansion tank upper to cylinder heads routing on select BMW models. The hose follows the original size, shape, and connector style used by the factory assembly, which helps maintain proper coolant routing and simplifies service on BMW 545i, 645Ci, 550i, and 650i cooling systems. This part cross-references Genuine 17127542540 for the same application.

What This Hose Helps Address

• Coolant leaks at aged or cracked hose sections
• Repeat seepage from worn quick connectors or O-rings
• Cooling system service delays caused by hose modification
• Poor fitment from universal hoses that do not match OE routing
• Heat and contamination-related hose deterioration

Installation Notes and Tips

Compatible With 2004 BMW 545i, Expansion Tank (Upper) To Cylinder Heads; 2004 BMW 645Ci, Expansion Tank (Upper) To Cylinder Heads; 2005 BMW 545i, Expansion Tank (Upper) To Cylinder Heads; 2005 BMW 645Ci, Expansion Tank (Upper) To Cylinder Heads; 2006-2010 BMW 550i, Expansion Tank (Upper) To Cylinder Heads; 2006-2010 BMW 650i, Expansion Tank (Upper) To Cylinder Heads. Verify the routing and connector style against the original hose before installation. Clean the mating surfaces and inspect the cooling system connection points for wear or contamination so the new hose seats correctly.

Quality Assurance

Rein Automotive focuses on OE quality replacement parts for European vehicles, with this hose built to match factory dimensions and connector design for consistent service results. CHE0523 is manufactured to support proper cooling system repair on the listed BMW applications.