Bad De-Mandate?

[fast69mopar]

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Hey guys. New member but a long time reader and lurker of the forums. My name is Michael and I am an O/O from Texas. I have a 2014 International 9900i that i bought back in December. The truck came from Canada too. Here are the specs:

ISX-15 CM2350 (Originally 550HP)
RTLO-18918B 18 speed
4.10 gears
13,220 Front Axle
46,000 Rear Axles
BD Exhaust Manifold
Borg Warner Turbo #171710 (S478)
Odometer Mileage: 504399
ECM Mileage appears to be just over 40,000 miles.

Quick edit: The truck sits on 11R/24.5 rubber and my cruise RPM at 65mph is 1500rpm. For this last 30 day average I ran the truck at 65mph at 1500rpm loaded and empty. I prefer to drive 57mph under normal time constraints and 62mph if I am in a hurry.
The truck had been De-Mandated before I made the purchase and I knew it was so it was not a surprise. I am a career mechanic from Chrysler that switched to trucking after 23 years of turning wrenches. I know the tune is way off in the ECM and my tuning experience with Cummins motors larger than the 5.9/6.7 is lacking.

This thing is a dog. As of right now my fuel economy 30 day average is 4.35mpg with a best of 5.12mph and a worst of 3.94mpg. I pull a 3-axle step deck and right now I weigh 68,000lbs and attempting to pull a 6% grade I see a maximum of 25psi of boost on the stock gauge and 26psi on my mechanical gauge. I also have very little black smoke if any. While pulling anything larger than a 3% grade I am having to drop down to 15th and sometimes 14th gear to maintain speed up the grade even at 68,000lbs. At 80,000-90,000lbs. I will be in 12th or 13th to maintain my speed uphill.

Is there any tuning guru's who would be willing to take a look at the current tune and provide some insight as to how bad it really is and what needs to be corrected?

Thanks for your time and glad to finally become a member of the forum.[/font]