XB Engines

Cummins and Detroit DD13 engines are best-in-class for diesel commercial bus chassis. Integrated with the latest technology and boasting horsepower ratings up to 330 hp, these engines will deliver the performance you expect when you need it most and provide a lifetime of no-hassle maintenance. And all of the latest engines are proven to meet emissions standards required for the 2010 legislation.

Cummins® Engines

Cummins ISB 6.7 L

Cummins ISB and ISL engines deliver:

  • Exceptional fuel economy
  • Extended oil-change intervals
  • Up to 500,000-mile engine life
  • Lowered engine position to eliminate doghouse

Cummins Engines

Cummins® ISB 6.7L 200HP 520 lb.-ft. torque
Cummins ISB 6.7L 220HP 520 lb.-ft. torque
Cummins ISB 6.7L 240HP 560 lb.-ft. torque
Cummins ISB 6.7L 260HP 560 lb.-ft. torque
Cummins ISB 6.7L 280HP 660 lb.-ft. torque
Cummins ISB 6.7L 300HP 620 lb.-ft. torque
Cummins ISL 9L (XBR only) 330HP 1,000 lb.-ft. torque

To review specs and information on particular Cummins engines, visit their websiteFor warranty specifications, visit our downloads page.

DetroitTM DD13® Engine

XBP Only

Detroit DD13

With billions of dollars invested, the work of the world’s top engineers, and millions of miles of real-world experience, the DetroitTM DD13® engine has proven reliable when it really counts. The same powerful engine featured in many Freightliner trucks, the DD13 gives your commercial bus a balance of acceleration, climbing power and speed. Its flat torque curve delivers responsiveness on demand that will conquer even the steepest grades.

DD13 (XBP Only) 12.8L 450HP 1,550 lb.-ft. torque


Smart, fuel-efficient design makes the most of every gallon

  • Get up to 7% better fuel economy* compared to an EPA 2007 Series 60
  • Pulls strong down to 1100 RPM so drivers can spend more time in top gear
  • Amplified Common Rail System (ACRS™) optimizes each injection event to minimize fuel consumption
  • Advanced cooling system allows for decreased fan on-time, minimizing fuel consumption
  • Selective Catalytic Reduction (SCR) virtually eliminates excessive, fuel-consuming regenerations
*Compared to the Series 60 EPA 2007 engine with comparable engine ratings and load weights.


Lower your cost of ownership with easier serviceability

  • Longest scheduled maintenance intervals in its class
  • Maintenance-free crankcase breather
  • Unmatched parts availability at your local Detroit service location
  • Common serviceability with other Detroit engines ensures trained technicians are available when you need them
  • Overall robust design provides B50 life of 1 million miles

Virtual Technician

Virtual Technician is a factory-installed onboard diagnostic system that puts you in control of your business 24/7. When a coach’s check engine light illuminates, data is immediately collected, providing a technical snapshot of the engine’s status before, during and after a fault code event. This information is sent to you and the Detroit Customer Support Center, where a trained representative can diagnose the issue, recommend service and even contact the nearest authorized locations with parts in stock. Put simply, Virtual Technician takes the guesswork out of engine repair, helping you to manage your business more efficiently.

Diesel Design


The XB Chassis comes equipped with a 90-, 100-, or 150-gallon rectangular aluminized steel fuel tank mounted between the rails for increased safety and reduced fuel stops.


A lowered engine position creates a lower center of gravity, which increases the stability of the bus for a safer, more comfortable driving experience. It also allows for a flat floor in the rear of the bus, increasing usable space.