I'd imagine they have quite a few of the 5.7 powerplants that still need
to be installed.  And do yoiu think that while Cummins is releasing it in
'07 Dodge may need a year or 2 to work it into their truck line?

Ken,

from:
http://www.turbodieselregister.com/06ntea/

We were however told that the Ram 2500 and 3500 models for 2007 will be
rolled out with the existing 5.9 liter engine.

end quote.

Whether they'll continue to build the current 5.9 or have enough 5.9's
stockpiled, I don't know.  Mebbe the 6.7 will be rolled out as an '07.5?   I
recall that the Diesel engine builders were busted by the EPA for "cheating"
their ECM calibrations and had to implement the new regs on an advanced
schedule.  That accelerated schedule was 2007, however there are differences
in how the things are rated by the EPA.  Like this:

Under the federal light-duty Tier 2 regulation (phased-in beginning 2004)
vehicles of GVWR up to 10,000 lbs used for personal transportation have been
re-classified as "medium-duty passenger vehicles" (MDPV - primarily larger
SUVs and passenger vans) and are subject to the light-duty vehicle
legislation. Therefore, the same diesel engine model used for the 8,500 -
10,000 lbs vehicle category may be classified as either light- or heavy-duty
and certified to different standards, depending on the application.

Clear as mud?  Yeah, it makes my head hurt too!

 Robert