The water outlet connects the engine to the upper radiator hose. When the
cooling system thermostat is located at the outlet it is sometimes called the
thermostat housing. Most water outlets are aluminum but can also be made of
cast iron, steel or nylon.
Many outlets come with plugs for when a vehicle requires a temperature switch
for one model but no switch for a second model.
Which Thermostat Is Right For You?
Type
Lifespan
Flow Rate
Precise Temperature Control
Fail-Safe Engine Protection
Economy
★
★
★
Standard Replacement
★★
★
★★
Performance
★★
★★
★★
Heavy Duty
★★★
★★
★★★
Premium
★★
★
★★
★
What Temperature Thermostat Do I Need?
Thermostats have a “rated” temperature (such as 180F or 195F). This is the temperature the thermostat will start to open, releasing heated coolant from the engine into the radiator. The thermostat will fully open once the coolant gets another ten or fifteen degrees warmer.
OE TEMPERATURE
These thermostats match the OEM-specified temperature rating for the vehicle. Manufacturers recommend an OE temperature thermostat for most engines, especially for:
Modern engines with computers that use the coolant temperature to help control the fuel, emissions and other important systems
ALTERNATE TEMPERATURE
These thermostats have a temperature rating below (cooler than) the OEM-specified temperature rating for the vehicle. This option may make sense for use in:
Modified Engines
Performance Applications
Older / Classic Vehicles
Cooling System Maintenance | Tips & Tools
Without regular maintenance, cooling system components will degrade and fail prematurely, which can lead to costly engine damage. Protect your engine with simple preventative maintenance:
Completely drain and flush the system using Cooling System Flush prior to installation. Flushing the system is critical to prevent system contamination and failure.
Consider replacing the Radiator Hoses (and Hose Clamps) and Radiator Cap as part of routine preventative maintenance. System contamination can cause these parts to degrade and fail over time, which can lead to severe engine damage from overheating.
Refill radiator with fresh Coolant / Antifreeze according to the volume and formula specified in your Owner's Manual. Inspect levels and condition every year.