Rein CTN0025 Engine Coolant Thermostat

OE Thermostat Insert for Cooling System Control

Rein CTN0025 is an OE quality engine coolant thermostat insert built for direct replacement service. It is calibrated to open at 80 degrees Celsius to help maintain proper operating temperature in the cooling system, with fitment coverage for select Audi, Porsche, and Volkswagen applications.

Compatible With 2006-2010 Volkswagen Passat, 2007-2010 Audi Q7, 2007-2010 Volkswagen Touareg, and 2008-2010 Porsche Cayenne applications, this thermostat insert is designed around original equipment specifications for a precise fit and consistent cooling performance.

Key Features

• Matches original equipment design specifications
• Thermostat set to 80 degrees Celsius for stable engine temperature control
• Manufactured to strict engineering standards for materials and tolerances
• Supplied with all gaskets or seals needed for installation
• OE quality construction using durable metal and plastic components
• Direct replacement thermostat insert for select VW, Audi, and Porsche cooling systems

Detailed Description

The Rein CTN0025 thermostat insert is engineered as a direct OE-style replacement for the original thermostat insert used in select 3.6L-era cooling system applications. Rein builds these inserts to meet or exceed OE material requirements, with temperature calibration and component quality chosen to support consistent coolant flow regulation. For drivers and technicians servicing a Volkswagen Passat, Audi Q7, Volkswagen Touareg, or Porsche Cayenne, this part number provides a focused replacement solution for cooling system maintenance.

This part cross-references 03H121113 and 95510612600 for the same application.

Common Issues This Part May Address

• Engine running too cool or too warm due to thermostat control issues
• Delayed warm-up after cold starts
• Temperature fluctuation from a worn thermostat insert
• Cooling system service needs on select Audi, Porsche, and Volkswagen models
• Replacement of a thermostat insert with degraded seals or housing interface wear

Installation Notes and Tips

Verify the part number and vehicle application before installation. This thermostat insert is application-specific and should be matched to the cooling system design used on the listed vehicles. Inspect the mating surfaces, replace any worn coolant seals as needed, and refill the system with the correct coolant mixture after service. Bleed air from the cooling system according to factory procedure to help prevent temperature irregularities.

Quality Assurance

Rein manufactures this thermostat insert to OE quality standards using durable materials and calibrated temperature response for dependable cooling system operation. The design focus is direct fit, proper sealing, and consistent performance for professional repair and maintenance work.