Looking at an 05 and it has failed the emissions test. What does that mean

Also is there a DPF on an 05

 

does it have a catalytic converter? if they removed that, it would most likely fail an emissions test.

i believe the dpf came about when they released the new 6.7 engine in the 2nd half of 2007

 

it could have failed the visual test, no cat, modded valve cover, stupid things. or it could have failed because of a tuner that was left in during the electronic sniffer

the DPF was used on 07.5 (6.7 only) and newer

 

No DPF, just a cat. Next chance you get, look underneath and see if there is a big can coming off the down pipe. If there isn't, that's the reason for the failed emissions test.