By Heather Burlingame, Senior Production Editor | September 28, 2010

CumminsThe QSK23 diesel engine maintains speed on uphill climbs with its six cylinders. A 29,000-psi high-pressure injection system provides fuel economy and maintains low emissions. Sensors send information to the Electronic Control Module to optimize air/fuel mixture to operating conditions. The engine has fewer parts than competitive V12 products, which minimizes downtime.