Found on another site, all correct??

In developing the new “600,” Cummins and Dodge made numerous other improvements or changes to the engine:

• Air inlet redesigned to block hot engine air from entering, reducing the intake charge by 30 to 40 degrees.
• Intake resonator re-engineered for increased airflow
• Larger compressor on Holset turbocharger
• Engine cooling improved with new fan assembly and mounting fan shroud to engine for more efficient airflow through radiator
• Upgraded intercooler
• Upgraded exhaust valves
• Tailpipe increased to 4-inch diameter
• Improved sealing and gasket materials
• Oil-change intervals are now 15,000 miles (vs. 7,500 for competition).
• Holset turbocharger gets bigger compression side
• Switch to electronic control of wastegate
• Upgrades to exhaust manifold
• Revised intake ports in cylinder head
• New piston bowl geometry
• Different spray pattern from injectors

 

In driving these new the 04.5 got less mileage, but had more pick up and quicker response when going from light throttle to half or full throttle. Electronic wastegate and different compressor were a big difference in stock configurations. But what fun is that? Most on here have not kept this anyway. Some later 04.5-05's got plastic ends on their i/coolers. Later switched back to metal.

Chris

 

catalytic convertor added to 600 models as well.

 

quick, where did you find this info, could you send links

 

http://www.pickuptruck.com/html/2004...ive/page3.html

 

thanks much

 

Along with about 4 mpg less...

 

I remember reading about better exhaust valve seats, higher boost, and a third injection event. As far as mileage, my '99 got 18.7mpg over 34K miles, my '02 ETH/DTT got 19.4mpg over 28K miles, and my '04.5 has managed 18.8mpg over 46K miles, 99% of it at altitudes over 6000ft, and including a cross-country trip with a 5Klb trailer. I did notice the '04.5 got the worst pre-break in mileage of the three, averaging less than 12mpg prior to the cross-country trip.