Truck maker Peterbilt Motors Co. of Dentoon, TX, is now offering the Cummins ISX engine in a 530-hp rating for its model 387, 379, 378 and 357 trucks. "This new Cummins ISX engine option is ideal for customers engaged in both on-highway and high GVW applications, such as tanker and heavy hauls," said Dan Sobic, Peterbilt’s assistant general manager. He added that this particular Cummins ISX rated engine can be upgraded to 600 hp with no hardware changes, which can enhance the resale value of the vehicle.