Should i change my 01 L Thermostat? What are the pros and cons if any. If it matters i did put a 4lb pulley on.

 

ttt

 

Pro: truck runs cooler CON: truck doesnt want to warm up when its 25 degrees outside lol!!!

 

I am getting ready to put the stock thermostat back in the truck because my truck keeps throwing a code with the 160* hypertech stat in it. It tells me I have insufficient coolant temperature for closed fuel system loop. What a crock

 

I'v been running a 170 deg thermostat since before summer, no problems...depends on the weather where you live....JR