Dont sacrifice performance or efficiency by running an engine too hot or too cold A failed thermostat can cause an engine to run at outside of its optimum temperature adversely affect performance and efficiency. The fix can be as simple as replacing the thermostat. Sierra makes it easy by packaging the thermostat with all the necessary components for an easy out the box installation. Kit includes thermostat rated for 140F and gasket. Engineered for use with 1998 and older GM based MCM in-line 4 and 6 cylinder engines. For 50 years Sierra has been producing parts engineered to meet or exceed the specifications of marine engine manufacturers and has gained the confidence of engine manufacturers and boat builders. Boaters and technicians can be assured a Sierra part will fit right the first time and restore function to OEM specifications. Key Features Thermostat meets or exceeds manufacturer specifications Complete kit includes thermostat, and gasket to eliminate time spent sourcing individual parts Compatible with 4 and 6 cylinder in-line GM based MCM engines The Sierra Engine Parts Selector In addition to thermostats, we offer a wide variety of other engine parts manufactured by Sierra. To see if we have the part you need, see ourEngine Parts Selector, where you can search by engine make, serial number and model or year of manufacture.ApplicationOEM Part NumberGLM13370Mallory9-43153