I am actually still on deployment and about to get honorable discharge back into the civilian world. got married to my highschool sweetheart i meet when attending kingston highschool and we got married in virgina where i was station, had a baby and decided i want to be a full time family man and husband so moving back to washington state. Tempory live in redmond, wa to get my feet back in and adjusted to civilian world. My wife dad has to get all his vehicles emission test every 4 years since there gas, i did reaserch with what internet i have overseas on deployment and the website states diesels older then 2007 needs it every 4 years and those 07 and newer dont but then some people say county only so i was confuse. I am a addict for 6.0 powerstroke i love them so i was just curious but it seems im safe so thats good, thanks everyone for your input god bless!