The bold style of the quantum provides a low engine tunnel creating a large open cab with greater visibility. Automatic stairs steps provide safe forward entry and exit form the cab Chassis Quantum® Engine Detroit Diesel DD13, Cummins ISX 12, L9 Engine Horsepower 400 - 525 hp Transmission Allison 3000 EVS, 4000 EVS or 4500 EVS Front Axle Suspension Leaf or TAK-4® Independent Front Suspension Rear Axle Suspensio Leaf, Rubber, Air, TAK-4®, or TAK-4® T3; Single or Tandem.