Has anyone tried a 200F thermostat on a 5.9 common rail? With winter here, I am hoping to get some more in cab heat when Idling around town. I was thinking of trying a 200f thermostat. I see some guys in the 2nd Gen forum are trying them, any experience on 3rd gens?

Unknown... :shrug:But I don't see too much issues with it. I did hear that AH64ID said something about the fan clutch?

If I understand the fan clutch could stay running due to water temp? is that the issue?

I think it would defeat the purpose of running a higher stat if it made the fan engage a majority of the time.JR

Unknown... But I don't see too much issues with it. I did hear that AH64ID said something about the fan clutch?

I read this in another thread as well, never heard of reprogramming the fan engagement, hopefully he sees this and can chime in. I am curious too.

Just seeing this thread. The programming is based on a 190 thermostat, meaning the fan operation is also based on that. Running a 200 and not towing shouldn't be an issue, but of you do any towing you will have a lot of fan on I time. 100% fan is commanded somewhere around 215, and a 200 thermostat is going to be full open around 215-217, and like 225 when very heavy. I would really like to run a 200, but the programming isn't there. I will add that if you have heat issues with a 190 then a 200 won't fix them, you have other issues like a plugged heater core. I get plenty of hot air in the cab at -25. I do highly recommend a winter front.