Probably because I got sick of working on them....Hahaha
It's pretty fun though!

Yeah we have 2, a 95 with a 7.3 powerstroke and a 94 with a 7.3 idi. I love them haha.

7.3 was a Great engine

Simple, the EPA, that communist organization has stopped many diesel ventures in the US, I know a guy who works on the diesels being designed for the future, 98% of the prototypes he tests and tunes are going to Europe, not only will they blow the doors off of anything here, they get over 40 MPG. He was testing out a Dodge Nitro diesel, brought it home, wicked sounding engine, there are single and dual over head cams available.

My understanding was that Navistar was built in Mexico and Ford has shifted production back to the US.

But then again....I don't know much about 'em...