So I got a 1990 22re base model I have a 190 OEM thermostat the temperature range is between 190 and 215 degrees when the truck Idles for a few minutes the truck climbs up to 200° the idle goes down around 75 RPMs to about 215°. When the truck hits 215° The temperature goes down and the idle goes back up and the truck goes back to 190 for a few minutes then it cycles again through the same thing. So my question is is that normal? I Used temperature gun on top thermostat housing for my temp reading

PS the thermostat is brand new the fan clutch is Brand new .