What size wheels?
 

Looking at the new 2013 Expedition specs, it can be had with either 17, 18 or 20 inch wheels. It seems the 20" tire is bound to be less compliant due to lower sidewall height, but if I have my choice, which rim size do I want? Criteria I look for in tires would be: Resistance to damage/ability to absorb impacts of bad roads; Serious tread; Load rating; and availability (is it a size that is widely used?) Anybody have any pointers while this still hasn't cost me anything yet?

I'd go with 17s, 18s if a must and try to avoid the 20s.

After 18, the "value" of the bigger wheel starts to become no value at all. The increase in unsprung weight negates any handling advantage. The tires are really expensive. Rim damage is certain when the potholes bloom.

IIRC, certain desirable option packages "require" the 20s, so good luck on that front.

tire size continued
 

Yeah, the 20s are one reason to not order the King Ranch pkg. And the split spoke on the 18s looks less robust than the solid one on the 17s. So since the 17 also gives the tallest sidewall height, it is the theoretical winner. But my '88 T-Bird has 14s, and they no longer make H rated 225/65-14 tires. So I have to run 112mph rubber on a 130mph car. Will the future bring another surprise like no cleated tread 17s? I hate to get stung on a new truck, now where's my crystal ball?