I have a 2011 FF150xlt 4x4 super crew with the ecoboost. ..what is the largest tire I can put on the stock wheels without leveling or rub issues...looking to fill the fender gap and get a bit wider of a stance...and of course taller is always better...

 

Keep in mind that the speedometer and odemeter will be off unless your PCM is reprogrammed.

 

Around a 33x11.50. Your not going to be going much wider without leveling at a minimum.

 

What exact size did it come with from the factory?

 

Stock tires are 275x65x18...not really looking to get into a whole lot of re-programming...just want a bit taller of a stance with more rubber on the road...

 

Please look on your door jamb sticker for the width of the stock wheels - the info I'm finding says they are either 7.5" or 8". This is going to be a limiting factor.

 

18x7.5J

 

You really can't go any larger - the design spec for the stock size is an 8" wide wheel, so it's already a bit oversize. You would have to get different wheels to do anything that's going to make a noticeable difference.

 

If you don't want a leveling kit or anything, 275/70/18 will add another inch, but the same width. 285/65/18 is a tad wider and 0.5" taller. Anything bigger than that and I can't guarantee they'll fit.

I agree with GLC that I wouldn't put a tire any wider than 285 or so on such a narrow wheel, though people do it all the time.