Motorad 521-180 Engine Coolant Thermostat Housing Assembly

Integrated Housing Thermostat for Cadillac Cooling Systems

The Motorad 521-180 is an engine coolant thermostat housing assembly built for OE-style cooling system service. It uses a 180 Deg. F opening temperature and an integrated housing design to help regulate coolant flow in Cadillac applications with the correct seal and outlet configuration.

Compatible With 2004-2009 Cadillac SRX, 2004-2007 Cadillac CTS, and 2005-2007 Cadillac STS, this Motorad Integrated Housing Thermostat is built for direct replacement service in vehicles that require a 180F thermostat housing assembly.

Key Features

• Part number: 521-180
• Integrated housing thermostat assembly
• 180 Deg. F start-to-open temperature
• Bleeder hole and jiggle pin included
• Rubber gasket/seal included
• Two bolt holes and two outlet ports
• Aluminum, stainless steel, and copper construction
• Silver finish
• OE-style seals and offset design where applicable

Product Details

Motorad’s Integrated Housing Thermostat line focuses on OE-spec cooling system service parts built with OEM-quality materials and manufacturing processes. The 521-180 uses a copper case and wax compound for quick response to coolant temperature changes, while the housing design includes an air relief feature and OE-style sealing surfaces where applicable. This part cross-references Dorman - OE Solutions 521-180 for the same application.

What This Part Helps Address

• Engine running cooler or warmer than expected due to thermostat wear
• Coolant temperature fluctuation during normal driving
• Leaks at the thermostat housing seal or gasket area
• Slow thermostat response from aging internal components
• Service replacement needs on Cadillac SRX, CTS, and STS cooling systems

Installation Notes and Tips

Verify the 180 Deg. F temperature rating and outlet diameter before installation. Inspect the mating surfaces, replace damaged hoses or clamps as needed, and confirm the bleeder hole and jiggle pin are oriented correctly during assembly. Follow the vehicle service procedure for coolant refill and air bleeding to reduce trapped air in the system.

Quality Assurance

Manufactured to OEM specifications by an OE supplier using materials and processes intended to meet automotive cooling system requirements. The housing includes a gasket/seal and hardware is listed in the product attributes; bolts are not included.