ford had the best when they had the 7.3 after that there are just pos,as of 2010 ford will be making there own diesel engines or i heard they might be puting cats in there truck,if they do that they might have the best,as long as there are useing the international navistar engine they are crap,and international cant even come up with there own injecters they have to steal cats and they are paying for that,only thing i am saying is the 2003 1/2 and up diesel are pos they should have never went to the 6.0 and 6.4