[cmitchell17]

I posted this here, and not in the issues section, because I know a lot of people like to put in aftermarket colder thermostats.

I notice that if not on the gas and just cruising around and not stationary, my coolant temps will go below 165F sometimes and usually stay around 165F unless I get on it of course. I know all GEN III/IV engines I've had would run always at around 200F even when its 30F outside and you are going 50mph down the road. I think they have revised a lot of stuff as far as the cooling system on these GEN Vs but I know its not supposed to be that cool?

I can't really remember how it was in the summer, but it seems like my thermostat maybe stuck open a little or maybe leaking coolant by?

Not sure if its worth it to try to pull the housing and test the thermostat in some boiling water. I've heard you have to order a whole new housing you can't just buy a thermostat, unless I guess you could maybe by an aftermarket one.

I tend to think way to thermodynamically, and want the hottest coolant temp that still is safe for the materials, gaskets, fluids, etc. which is basically how its run from the factory. Yes I know people run aftermarket cooler ones in an attempt to reduce knock and try to get back to best timing. I think more along the lines of coolant robs torque the colder you let it get the more heat transfer and the more energy wasted out the radiator. It would be an interesting calculation to do the math to see if the cooler thermostat temps rob more energy than what is gained by restoring optimal timing, I run E85 all the time so I'm not concerned.