Well I can tell you that a local grocery store company who has thier warehouse in town here, used to run used oil in thier semi's thought it was a good idea ran approx 10-15% and only used thier own oil from doing oil changes on the truck and ran it through a proffesional cleaning system made just for this purpose. The max ever ran was 25% as a trial ended up they now pay someone to take thier used oil the $9000 cleaning system sits in a corner and they use nothing but B20 and regular diesel. the reason well simple thier fuel filter costs tripled, the onroad repair bills for fuel related problems doubled, the amount of injectors replaced on an anual bases quadrupled (and at over $200 each your really going to like replacing them every year) And they replaced fuel pumps on almost half the trucks and this was so rare until they started running used oil they didn't even keep fuel pumps in stock but afterwards well they kept several in stock. Well it took them 2 yrs after they quit using it to quit having injector problems and fuel pump problems but hey it's your truck hope it works out for you, but when it triples your operating costs don't come back and wonder why no one warned ya cause several have.