That is entirely up to you. When I purchased my truck I had my dealer swap out my stock 235/75/17's for 265/70/17's and did not recalibrate. I would call to find out what your particular dealer charges. By the way, the 255/70/17 tire is almost identical (less than a 1/4" diff.) in height to your stock 235/75/17, and your speedo would be almost dead on. Remember, you will lose at least 1/2" off the diameter of your tires before you replace them again.

 

LOL! You callin me a poser?

That was me that did the sticker, and yes, it's a 4x4.

The stock size I had before the change, were 255 70 17's, so going to a 275 70 17 only put my speedometer out roughly 3%. I have a calculator here to figure it out, but I'm lazy, and to the best of my recollection, that was what I figured out before buying that size. I didn't get the PCM flashed for the correction, but I can live with driving at 100 km's knowing I'm actually doing 103 km/h.
That was why I went with a 275, because it was close enough without having to worry about recalibration, it really won't hurt my gearing, and they're a good bit beefier than the stockers.

I'm not sure if they'd work with a 4x2, but I suspect they would work fine. You'd be jumping from a 235 to a 275 with the same sidewall, so the diameter would be jumping up quite a bit. You'd need a recalibration, unless you already have a tuner.

As for all those tire sizes, play with this calclator. It's fun.

http://www.discounttire.com/dtcs/infoTireMath.dos

 

Wreckin Crew; further to my post above, I don't know if you've seen this review yet, but it's good for a read. These are all AT tires. Notice the Americraps at the very bottom? That was what I had from the factory:

http://www.tirerack.com/tires/surveyresults/surveydisplay.jsp?type=ORAT

 

Michelin was one of the OEM tires for an '04 F150.

My first new replacement set of tires were Cooper ATR.

Coopers are very good tires. I'm sure there are some that dislike Coopers like other brands.

Anything would have been better than the Continentals that were on it when I bought my '04 F150.

 

I have An 04 F-150 2-wd, and I'm running 265/70/17 Michelin Cross Country's and they are great. Long wearing ,quiet, good traction in heavy rain, I should get 60-k on them. 265/70/17s will fit your rims, as mine did.
1950-F-1
1996 Ranger
2004 F-150

 

Jesus Lastoh, those ameritrack ratings are dirt poor. Im surprised youre still alive lol. Thanks for all the input guys!

 

Ha!
You won't find many compliments from people that have those tires! I don't know why Ford puts P rated tires on a full sized pickup truck. LT tires should be standard IMO.