Fuel mileage on USA Truck 09 Prostar, cummins, 455hp Eaton UltraShift, APU

As a former USA Driver I never drove the Navstar but did drive the automatics and was not impressed. Best I got was 6.2MPG With a 10 speed manual Freightshaker I was getting 6.9 to 7.2. Also USA Trucks are abused a lot.

 

I had an 09 Prostar for a couple of years. It ran good most of the time. The cummins is a great pulling engine. You should expect to get 6.8 or higher mpg. The engine should last longer than the same truck without an APU because of the idleing it did not have to do.
If it has not had the particulate filter changed recently it may be needing it soon. If it shows a lack of power or loss of it, that is a common problem area.
Since you most likely will not have it goverened at 63 like when we had it, this will be less of a problem for you. Running them slower shortened the DPF life cycle.

 

http://www.thetruckersreport.com/tr...3-cummins-isx-cm871-technical-discussion.html
Might want to keep this thread handy all but if you follow the routines in this thread you can almost guarantee trouble free performance out of a Cummins.