You will see from my signature that we own a 2006 Ford 6.0 L diesel. This truck has runs and pulls like a dream. We have not had one single issue with it since day one. I prefer Ford over Chevy for several reasons, mostly personal, but feel up until 2011, Ford has made a superior product. If looking at a 2011, though, would now have to strongly consider Chevy also. That being said, we also had a 2003 6.0 that was nothing but problems from day on until we traded it on the 2006. The Ford 6.0 L diesel was a very problematic engine between 2003 - 2005. I have heard and read that if a 6.0 runs good up to 30,000 then it is probably a good engine. Our 2006, has not had a single issue and is still running strong, but only has 36,000 on it. However 90% of the miles are towing, so appears that the second time we got a good 6.0. I would recommend you request a service report on both trucks and compare. If the ford has had any major warranty work performed, it could very well be one of the problem engines built between 2003-2005. Good luck with your choice.