[therockhound]

2002 f350, 7.3 turbo. dually, cc. Used to get 17mpg for past 350,000 miles now all of the sudden getting 14mpg. Checked tires, used additives to clean, same driving habits. Thoughts?

 

[RT]

Fuel pressure, a bad sensor (like the ICP sensor), blocked EBP tube, boost leak (most likely), dragging brakes, and probably a half dozen other zebras we can explore when you've checked the more common issues.

Do you have any gauges? I highly recommend you have a fuel pressure gauge on top of the trans temp/boost/pyro that should be on everyone's truck already.