Hello,
I have the 18" wheels that came stock with my 2014 FX4.
I would like to swap them out for the 20" that were also available for this trim.
Will I need to re-configure the computer so it knows the wheels are now 20"?
Thanks,
Zuper

 

Not if the tires have the same diameter.

The 18's came with 275-65's which are 32's.
The 20's came with 275-55's, which are also 32's.

If you go with a different size, a correction should be done.

 

Ok, but the overall wheel size (rim and tire) seems bigger.
When equipped with 20s the wheel well just seems more filled.
Maybe just an optical illusion.

 

That's all it is because the wheel is larger - assuming I'm correct on your before and after tire sizes.

 

Like glc said, there is no change in the diameter.

 

The diameter of the wheel (rim+tire) will be the ~same. IF any difference is discerned, it is an optical delusion. The variances between 18" > 20" are slight. *.attachment
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