what should the average temperature be for the gmc denali while driving? on 2006 GMC Yukon Denali

The temp gauge is reading between 150 and 200 while driving. It normally is between 100 and 150. Do I need to have this checked?

Asked by for the 2006 GMC Yukon Denali
My book shows the stock thermostat (AC Delco) at 187 degrees, So it sounds like it was stuck in the open position, But maybe you should have it replaced before it sticks closed and causes the engine to overheat and you can find a shop here or check thermostat replacement cost here