While on this topic... I have to vent a little...
One of the things that I have discovered at my new dealership is that the previous diesel tech was a huge advocate of tuners, DPF removals (I hate the word "delete", as it is merely and attempt to make it sound like a factory option)... I have people coming in left, right and center with the stooopidest complaints. I had a guy with no DPF and a tuner complaining of a lack of power, to which I replied I won't even attempt to look at it unless you reinstall the pollution control devices and the factory tune. I did drive the truck, and it just about gave me whiplash when I took off. I'm working on a 2008 6.4 right now, with DieselCare ESP. We all know DieselCare for a 6.4 isn't cheap. I believe it's over $5000. The engine is dusted AND has a burnt piston. It also has a tuner, no DPF and a shitty AFE intake. We told the customer straight up that he is on the hook for all the diagnosis and tear down unless Ford authorizes the claim. The guy was pissed. As it turns out, this engine was already replaced once in 2011, and the "tech" who replaced the engine actually took it to a performance shop just up the road from us and had the tuner installed on the post repair roadtest! The customer told us that said "tech" said not to worry about warranty implications, because nobody will ever know if he keeps coming to us... THEN I CAME ALONG!
FWIW, the authorization for the engine repair is still under review, as Ford is reviewing IDS files AND sending an inspector.