ACDelco Engine Coolant Thermostat 187°F with Gasket — GM Original Equipment 131-160 (89018168)

This ACDelco GM Original Equipment thermostat kit includes the temperature-controlled valve and the matching seal required for a correct installation in many GM vehicles. Built to original-equipment specifications, the thermostat fits like the factory part and is recommended by GM as a direct replacement. Designed to open at 187 degrees Fahrenheit, it manages coolant circulation between the engine and radiator so the engine warms up efficiently and maintains steady operating temperature.

How does this thermostat affect engine temperature control?

The thermostat is a temperature-sensitive valve that restricts or allows coolant flow based on coolant temperature. When the coolant is below its designated set point the valve stays closed to expedite warm-up; once the coolant reaches about 187°F the valve opens to let coolant flow to the radiator and stabilize temperature.

• Opens at approximately 187°F to begin radiator cooling
• Closes when coolant drops below set point to aid warm-up
• Works with OEM mounting and housing for accurate operation

What comes in the kit and why is the gasket included?

This kit supplies the thermostat assembly plus a new gasket/seal engineered for a tight, leak-free installation. Replacing the gasket whenever you change the thermostat helps avoid coolant leaks and ensures the thermostat sits correctly in the housing.

• Thermostat pre-calibrated to GM OE temperature specification
• New gasket included for a reliable seal at the housing flange
• Reduces risk of air pockets and coolant leakage after installation

Will this ACDelco part fit my GM vehicle and match original performance?

ACDelco GM Original Equipment parts are manufactured to match the fit, form, and function of the factory component. This thermostat is produced to GM OE tolerances and recommended as the direct replacement for the corresponding original thermostat part numbers in compatible models.

• Manufactured to GM OE specifications for consistent fit
• Designed to provide the same service life and durability as factory parts
• Check vehicle compatibility by part number or OEM cross-reference

How do I know when to replace the thermostat?

Signs the thermostat may need replacing include overheating, temperature gauge fluctuations, or coolant leaks around the thermostat housing. Because thermostats and seals can wear over time, replacing them as part of cooling system maintenance helps maintain engine performance.

• Visible coolant leaks at the housing or gasket area
• Engine temperature spikes or hard-to-reach normal temperature
• Routine cooling-system service or replacement during repairs

Who is this product for: The ACDelco GM Original Equipment 131-160 (89018168) 187° thermostat kit is intended for GM owners, independent mechanics, and technicians who want a direct-fit replacement built to factory standards. It suits anyone servicing the cooling system who requires an OE-quality thermostat and gasket to restore proper engine temperature control without modifying the factory setup. Use this kit when you need a reliable, specification-matching component for routine maintenance or to resolve thermostat-related temperature issues.