The 5.9L H.O. Cummins debuted in mid-2004 and continued through to mid-2007. To easily identify the 04.5-07 motor there is a white label on the driver side of the valve cover that has engine specs, there is a line that states engine horsepower and it will read 325hp (if it reads 305hp, it is a 03-04 Cummins motor). The 04.5-07 Common Rail Cummins is the 2nd generation of common rail B series motor. Like the 03-04 motor, the H.O. utilizes a high pressure common rail injection system backed by a CP3 capable of 24,000psi which feeds into a common rail, distributed amongst 6 Bosch injectors. The 04.5-07 H.O. has a slightly more advanced CAN bus system with a multi-pulse injection system that communicates to the individual injector solenoids. The ECM is more advanced as well which opens doors for fine tuning stock or modified builds. The turbo was upgraded on the 04.5-07 Dodge Cummins trucks from a standard 4” HX40 style flange to a 4-3/8” “wide mouth” Holset HE351CW Turbo (it is crucial to know if the truck is a 04 or a 04.5 for proper fitment of turbos, exhausts, Tuning, etc. The 03-09 Dodge Diesels are considered as a third generation body style, but there was a defined front end change between 2005 and 2006, the grille, front bumper, front fenders, and headlights all changed to a new style. Like in earlier years, the 04.5-07 Dodge truck still had front suspension/steering issues with the Y-style steering linkage which can create death wobble under load or acceleration. The 04.5-07 Cummins is equipped with a 48re transmission which are great transmissions, they are just built weak from the factory. An upgraded transmission rebuild kit or crate transmission and torque converter will make these transmissions near bulletproof. Also the 04.5-07 Dodge could have been equipped with a NV5600 or G56 manual transmission.