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We Know Quality

For helping to maintain optimal engine temperatures, NAPA Thermostats are an aftermarket alternative that meets OE specifications to ensure a long-lasting installation for your engine cooling system.

We Know Our Products

Using a reactive expanding wax, NAPA Thermostats adapt to changing temperatures to control the flow of engine coolant, redirecting coolant to the radiator to help reduce heat and keep your engine performing as intended.

The Rules of Cool

NAPA tests all its thermostats to rigorous standards to guarantee we meet every possible quality assurance checkpoint with expert precision. These tests include:

  • Visual & Dimensional Analysis – Using 3D imaging to measure and compare against OE samples.
  • Hardness Tests – Measuring and controlling the hardness of metals and rubbers to ensure they are identical to OE samples.
  • Spectrometry Test – Controlling the chemical composition of rubber and plastic materials to meet OE standards of deviation.
  • Thermogravimetric Analysis – Detailing the composition of rubber using controlled temperature and atmospheric conditions.
  • Temperature Checks – Measuring opening temperature and functionality between NAPA parts and their OE counterparts.
  • Tightness and Leak Value Tests – Checking for potential leaks using compressed air immersed in water to ensure a margin of 40ml/h or less.

We Know How

At NAPA, Know How is everything. All NAPA Thermostats come with a 3 year/36,000-mile guarantee and are manufactured at ISO 9001:2015 approved standards to guarantee quality or protection against unexpected faults.

Our team of technical experts are on hand to provide support and guidance on our range of thermostats. This can cover anything from installation best practices to regular content releases addressing frequently asked questions regarding our product ranges. Quality may begin with the product, but there is never an end to our Know How.

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