I'm not sure but I think it has an aftermarket exhaust, I haven't really bothered to look.
It is fully loaded and has pretty much mint leather seats and all that jazz. We picked it up for 10g (as said before) and had about 89,000 on it when we picked it up. Now has 95,000 on it.
I do not know if it screams (for apparent reasons) and I've been forbidden from driving it.
EDIT: well, my mom did tell me that when she was towing her camper with her cousin (drives a Ford Powerstroke with a camper as well), the powerstroke could not keep up with mom when going up a steep incline.