oil in radiator coolant tank

Not at all, I haul transmission poles.
My runs average 650-700 miles always m/t back where I usually must travel through 2 or 3 major cities each way and fuel saving mode wouldn't get me back. I always leave out 3 or 4 am and always make better time going out loaded than returning m/t.The D13 is really and awesome motor,I never seen nothing like it as far as pulling power.