Mishimoto high Performance intercooler, watercooler, oilcooler and oil-catch cans Low-Temperature Thermostat Mishimoto Chevrolet/GMC 6.5L Diesel / 97-99 MMTS-WRA-87L Mishimoto high Performance intercooler, watercooler, oilcooler and oil-catch cans Category: Racing Thermostats OEM Activation Temp C: 90°C Mishimoto Activation Temp C: 82°C Mishimoto is proud to release a racing thermostat engineered to improve the cooling efficiency of your 6.5L diesel. Whether you are cruising down the highway or hauling a heavy load, an effective cooling system is critical to the life of your engine. Mishimoto racing thermostats promote greater cooling efficiency by significantly decreasing high engine temperatures. Once the engine is fully warmed up, the Mishimoto low-temperature racing thermostat will open at a lower temperature (82°C) compared to standard thermostats (90,5°C). This allows coolant to flow through the engine sooner, thus reducing and maintaining cooler engine temperatures. Decreased temperatures will result in reduced engine wear and improved reliability. See for specific vehicle fitment information or contact us.