I talked to a trusted 7.3 mechanic in my area. He told me 2 or 3 things my problem could be off the start. He said that the service engine light coming on over a grade with a stock truck is not overboost, it is a clogged exhaust back pressure sensor. So, I pulled it off yesterday, and the sensor and the tube were filed with soot. I doubt it has been off since new. The tube also had a hole in it. I'm going to buy the tube from the dealer but if anyone on here knows of a cheaper place to get the sensor it would be greatly appreciated.