DPF reduces fuel mileage by 4-5 mpg. The DPF uses fuel every 350-400 miles to clean out the filter resulting in high EGTs.
Trucks with DEF have a high rate to reoccurring issues. It is a flawed system. Adding a 9th injector did little to help the emission issues.
If you want to talk about tuning, school us on EFIlive :-)
