News Releases

Oder Books Open for New Class 8 Diesel, as MaxxForce™ 11/13 Engines Launch
Class 8 buyers now have integrated powertrain choice
The new MaxxForce™ 11 and 13 big bore engines will power the International® ProStar, TranStar™ and WorkStar™ Class 8 vehicles.

LAS VEGAS (Jan. 24, 2008) – Order books opened this week for the most advanced Class 8 integrated diesel powertrain at International dealerships across North America. The new MaxxForce™ 11 and MaxxForce 13 big bore engines now offer heavy commercial truck buyers a fuel-efficient, powerful, durable and startlingly quiet powerplant in an integrated truck-engine package backed by the largest channel of commercial truck service locations in the United States and Canada.

Designed and engineered specifically for International® brand Class 8 trucks, the MaxxForce big bore engines are offered as an option exclusively in models of the International® ProStar™ line-haul tractors, TranStar™ regional-haul tractors and WorkStar™ severe service vehicles. Six MaxxForce big bore models offer ratings in the ranges of 330 to 475 horsepower and 1,250 to 1,700 lb.-ft. torque (see chart).

“Anticipation has been high since we announced our strategy nearly three years ago,” International Engine Group President Jack Allen said at a media ride-and-drive event here, “and this world-class product will exceed expectations. But its true impact can’t fully be realized until you hear it, drive it and learn about its advanced systems.”

Built on a compacted graphite iron block – the first for the North American Class 8 market – the MaxxForce 11 and MaxxForce 13 feature fuel system electronics, air-management system, EGR, and aftertreatment technologies developed by International specifically for high performance at low emissions levels. These advanced features yield four primary benefits for International vehicle owners: Outstanding fuel economy, excellent power and torque, quiet operation with low noise, vibration and harshness, and high strength without added weight.

The outstanding efficiency and power characteristics of the MaxxForce 11 and MaxxForce 13 – made possible by innovative technologies including a high-pressure common-rail fuel system, twin-series turbochargers with interstage cooler and Eco-Therm™ heat-management system – set new industry standards for heavy-duty diesel performance, drivability and fuel efficiency.

The advanced fuel- and air-management systems provide instant response to reach peak torque at 1,000 rpm. This means earlier acceleration upshifts and fewer grade-climb downshifts. This keeps MaxxForce big bore engines operating more often in the lower speed range – where fuel economy is inherently best. Other 11- and 13-liter engines do not achieve peak torque until higher engine speeds.

The new MaxxForce 11 and MaxxForce 13 are the first outcomes of the collaboration between International and MAN Nutzfahrzeuge, announced in early 2005. Both global companies contributed to the design, development, engineering, sourcing, testing and manufacturing of the technologies, systems and components. The MaxxForce 11 and MaxxForce 13 engines will be manufactured at a new International plant in Huntsville, Ala.

For more information on MaxxForce 11 and MaxxForce 13, visit For details about the entire line of MaxxForce commercial diesel engines, visit

A wholly owned subsidiary of Navistar International Corporation (Other OTC: NAVZ), International Truck and Engine Corporation is a leading producer of medium trucks, heavy trucks, severe service vehicles, MaxxForce diesel engines, parts and service. International and its affiliates sell their products, parts and services through a network of nearly 1,000 retail outlets in the United States, Canada, and Mexico and from 139 dealer locations in 52 countries throughout the world. Additional information is available at:

Media Contacts:

Bob Carso                                                 Patrick McAuley
(708) 865-3484                                        (312) 422-5942 


Horsepower                  Peak Torque                 Gov. Speed (rpm)                      Clutch Engagement Torque
    (bhp)                             (lb.-ft.)                     On-hwy / Severe Service                        @ 800 rpm
     410                               1,450                           1,900 / 2,100                          830
     430                               1,550                           1,900 / 2,100                          830
     475                               1,700                           1,900 / 2,100                          960
Horsepower                  Peak Torque                 Gov. Speed (rpm)                      Clutch Engagement Torque
    (bhp)                             (lb.-ft.)                     On-hwy / Severe Service                         @ 800 rpm
     330                               1,250                           1,900 / 2,100                          660
     370                               1,350                           1,900 / 2,100                          760
     390                               1,400                          1,900 / 2,100                           830