Here is whats going on. At 40k miles OEM thermostat fail, stuck open wiith cel P0128 so i decide to buy Katech 174f thermo because all other aftermarket brand had issues. Right after install this thermostat at hwy speed higher than 30mph it starts to overcool, and a lot. I seen 125f. At idle and around town traffic it will heat up to 185f. I did change fan setting in HP tuners for 174 thermostat and im sure fans dont cool it down to 126f. I set them up % at 185 and up, disabled P0128. I installed Katech thermo in brand new OEM housing with new spring so thats not issues. I pulled it out and it wasnt stuck open like OEM was. I had extra new OEM thermostat with housing and springs so i went back to stock one. It runs fine now and heats up in 200s lol. Katech never had anyone complaing about their thermostat. I dont know whats deal.
I know someone is gonna say why do yoi need lower thermostat, well i had lower thermostats in my other vehicles and OEM thermo in Gen V LT will gets up to 215. Yeah it may help lover emissions and gets better mpg, but i didnt buy 6k lbs SUV to save on MPG and save planet lol
I know someone is gonna say why do yoi need lower thermostat, well i had lower thermostats in my other vehicles and OEM thermo in Gen V LT will gets up to 215. Yeah it may help lover emissions and gets better mpg, but i didnt buy 6k lbs SUV to save on MPG and save planet lol
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