We have a 04 with just over a million miles 3rd turbo 2nd water pump and various egr issues  a 1 head gasket original injectors and bearings. The 07 and the 01 have less than 500,000 and are basically all orginal and get between 6and 7 mpg in T-600 KWs pulling hoppers, all are 475 or 450 hp.I really want to delete the emmissons stuff on the 07 and make it like the 01 engine, it seems like the egr engines run hotter. I really do not like the turbo on the egr engines very expensive and short lives.