Thermostats

Thermostats: the valve that decides how hot your engine runs

A coolant thermostat is a temperature-controlled valve sitting between the engine and the radiator. Cold, it stays shut so the engine warms up quickly; once it hits its rated opening temperature it lets coolant flow to the radiator to shed heat. People replace thermostats because the original stuck, ran erratic temps, or because they want a lower opening temperature to keep intake and cylinder temps down under boost or hard track use. A low-temp unit opens sooner, so the cooling system starts working earlier - useful on a modified engine that makes more heat than stock.

What ThreePiece stocks

This category holds 94 thermostats across 6 brands, with current pricing from $22 to $186 for what is in stock. That range reflects the mix: simple stock-replacement valves at the low end, and housing-integrated or in-line oil units at the top. Mishimoto is the largest presence at 81 products, followed by Gates with 5, Granatelli Motor Sports and ISR Performance with 3 each, and single listings from All Balls Racing and Vibrant.

Concrete examples: the Mishimoto In-Line Oil Thermostat (MMOP-EXTFC) at $185.67 controls oil rather than coolant flow; the Mishimoto 6.0L Powerstroke Low-Temperature Thermostat with CNC housing at $166.67 targets diesel trucks; and the Granatelli 180-degree thermostat for Dodge 5.7L/6.1L/6.4L and Hellcat runs $72.18.

How to choose

Two decisions matter. First, opening temperature. A lower-temp unit like the ISR 68-degree thermostat for the Nissan VQ35DE or the 68-degree unit for the VQ35HR and VQ37VHR opens sooner to hold coolant cooler; the Granatelli 160-degree thermostat for 98-17 GM LS does the same on LS engines. A lower opening temp can hurt warm-up time and daily driveability, so pick to match how the car is used. Second, whether you want a bare valve or a housing-integrated part - the CNC-housing Mishimoto units cost more but bundle the housing, while a plain replacement keeps price near the bottom of the range.

Fitment coverage

64 of these products carry fitment data, spanning years 1975 to 2030. Top makes include Ford, Chevrolet, Nissan, Toyota, Mazda, Jeep, Honda, BMW, Hyundai and Dodge, with named vehicles such as the Chevrolet Corvette, Ford Mustang, Ford F-250, Nissan 350Z, Mazda Miata, Jeep Wrangler and Toyota Supra. Always confirm against your exact year, engine and trim.

What else you need

When a thermostat is out, it is the right time to check the rest of the cooling and sealing system. Look at radiators if the old one is tired, and grab any gasket kits or head gaskets the job exposes. Plumbing changes often need fittings and adapters. Browse everything in the Engine Components section for the wider picture.

Fitment help and ordering

Not sure which unit fits? Call fitment help at 813-535-5801 or reach us through contact us. All orders ship free, and Affirm and Katapult financing is available at checkout - see financing for details.

Thermostats: the valve that decides how hot your engine runs

A coolant thermostat is a temperature-controlled valve sitting between the engine and the radiator. Cold, it stays shut so the engine warms up quickly; once it hits its rated opening temperature it lets coolant flow to the radiator to shed heat. People replace thermostats because the original stuck, ran erratic temps, or because they want a lower opening temperature to keep intake and cylinder temps down under boost or hard track use. A low-temp unit opens sooner, so the cooling system starts working earlier - useful on a modified engine that makes more heat than stock.

What ThreePiece stocks

This category holds 94 thermostats across 6 brands, with current pricing from $22 to $186 for what is in stock. That range reflects the mix: simple stock-replacement valves at the low end, and housing-integrated or in-line oil units at the top. Mishimoto is the largest presence at 81 products, followed by Gates with 5, Granatelli Motor Sports and ISR Performance with 3 each, and single listings from All Balls Racing and Vibrant.

Concrete examples: the Mishimoto In-Line Oil Thermostat (MMOP-EXTFC) at $185.67 controls oil rather than coolant flow; the Mishimoto 6.0L Powerstroke Low-Temperature Thermostat with CNC housing at $166.67 targets diesel trucks; and the Granatelli 180-degree thermostat for Dodge 5.7L/6.1L/6.4L and Hellcat runs $72.18.

How to choose

Two decisions matter. First, opening temperature. A lower-temp unit like the ISR 68-degree thermostat for the Nissan VQ35DE or the 68-degree unit for the VQ35HR and VQ37VHR opens sooner to hold coolant cooler; the Granatelli 160-degree thermostat for 98-17 GM LS does the same on LS engines. A lower opening temp can hurt warm-up time and daily driveability, so pick to match how the car is used. Second, whether you want a bare valve or a housing-integrated part - the CNC-housing Mishimoto units cost more but bundle the housing, while a plain replacement keeps price near the bottom of the range.

Fitment coverage

64 of these products carry fitment data, spanning years 1975 to 2030. Top makes include Ford, Chevrolet, Nissan, Toyota, Mazda, Jeep, Honda, BMW, Hyundai and Dodge, with named vehicles such as the Chevrolet Corvette, Ford Mustang, Ford F-250, Nissan 350Z, Mazda Miata, Jeep Wrangler and Toyota Supra. Always confirm against your exact year, engine and trim.

What else you need

When a thermostat is out, it is the right time to check the rest of the cooling and sealing system. Look at radiators if the old one is tired, and grab any gasket kits or head gaskets the job exposes. Plumbing changes often need fittings and adapters. Browse everything in the Engine Components section for the wider picture.

Fitment help and ordering

Not sure which unit fits? Call fitment help at 813-535-5801 or reach us through contact us. All orders ship free, and Affirm and Katapult financing is available at checkout - see financing for details.