Information provided below is based on the details provided by the manufacturer of this vehicle to NHTSA in the part 565 submittal Series:Trim: Gross Vehicle Weight Rating: Class 8: 33,001 lb and above (14,969 kg and above)Axles: Cab Type: MDHD: ConventionalAxle Configuration: Engine Displacement (L): 15Cylinders: 6 Drive Type: 6x4Engine Model: ISX Primary Fuel Type: Diesel Electrification Level: Secondary Fuel Type: Engine Manufacturer: Cummins Engine Brake (HP): 425Transmission Style: Transmission Speed: