i own a 2007 for 6.0 f350 the truck is running like crap but the check engine light dosent come on what should i do

I'd blame the EGR valve~ seems to be the most common culprit because it's job is to divert exhaust gasses back into the intake, well after a while it does get clobbered up with carbon and won't shut off~ you can disassemble and clean it with a little brake cleaner and put in fresh gaskets and stick it back in, or buy a brand new one, they are usually under 40 bucks~ http://www.youtube.com/watch?v=f5ToASEao8U

Got any enemies? Maybe watery gas.

It could be the EGR as Judge said. How old are the plugs, filter, wires, etc?

I don't know I just got this truck bout 4 months ago and its already giving me problems ahh ima go get a diagnostic test ran on it ill keep you guys posted...

see your smog guy. Make him work for a living instead of standin' around with a clipboard~