Well I installed a SCT tuner at the same time i did the intake so needless to say there was a huge performance increase combining the two. As far as mileage goes, it has gone down some but i contribute that to me not being able to keep my foot out of it!
Were you concerned about warranty implications with either of the above changes? (And change your sig file now - it's outta date!

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I took my truck to the main dealer for it's first service yesterday - decent guys, and (I think) sound advice: their take is: add a CAI if you want, if there are any potential warranty claim issues 'under the hood', then (since I bought the truck from them) be sure to have the OEM CAI in the bed of the truck at the time of all/any services, just in case they need to send pics for warranty claims to Ford (they'll change it out for any pics).
I didn't ask them about tuners, but they did suggest leaving cat-back exhausts until post-warranty, unless I wanted to change it before each service (or pay them to un/reinstall, again, in the event that pics for warranty purposes are required)
Just interested to hear your take, and that of any others in this regard. My personal take? You just can't put enough fresh cold air into a combustion engine , so I can't wait to add one - but I'd also be interested to hear whether anyone has had a dealer cause them warranty claim issues because of a CAI (sorry - not trying to thread-jack... if this should be a separate thread then just say!)