I've run heated wvo in my '02 Ford 7.3 Powerstroke since 2004. It does work but it does require attention.
I strongly suggest using a centrifuge to filter the oil.
PA Biodiesel Supply : Waste Vegetable Oil Cleaning : Biodiesel Centrifuge : Motor Oil : Water Removal : WVO Filtering : Dewatering Centrifuge : WMO Filtration Units has some good units at much better prices than I paid back in the day.
By the way, I've gotten as much as 367 miles to a gallon of diesel using heated wvo. That means I started and stopped the day driving on "store bought" diesel and spent most of the time running on free, filtered and heated veg oil.
I'm glad to help in any way I can... including the mistakes I've made. Oh, and I'm in the chemical business so this is right up my alley.