I know the 2007.5s through 2009s had some problems, but I never had emissions problems in the 2 years out of 9 that I ran emissions on my 2009 4500.
I had my 2010 3500 for 8 years towing my 5th wheel without a single emissions problem.
I know the 2007.5s through 2009s had some problems, but I never had emissions problems in the 2 years out of 9 that I ran emissions on my 2009 4500.