Cummins engines, especially the newer ones like the ISX, generally have a wider powerband than DD15 engines, allowing them to operate better at a range of operating speeds. The ISX line of Cummins ...

This particular Class 8 Peterbilt 587 uses a high-efficiency Cummins ISX15 engine and managed to average 9.9 miles per gallon over 11 runs over the 312-mile route between Fort Worth and Vernon ...

The X15 debuted in 2017 as an updated version of the ISX15. The X15 is also used in ... Two other Peterbilt models that use both PACCAR and Cummins engines are the 537 and 548, which can be ...