Where do E4OD's normally run? I just put a temp gauge in mine... I put the sensor in the pressure line to the oil cooler in the radiator so I can see how hot the oil get's before it reaches the cooler. It runs about 150 once it gets warmed up (Takes about half an hour) and it'll get up to 180 if I'm pulling hard with a trailer until I get out on the highway and then it'll drop down to 140-160. I usually don't haul anything too heavy (I ran across the scales at the scrap yard at 15,980 lbs with a trailer). Should I look at additional coolers or is the factory one pretty good?