We bought an 07 King Ranch F150 on Saturday. Very sweet truck! It has really nice 20" Pirelli's on it. I looked at the spare out of curiosity and noticed it is the original 18" Michelin. I called the sales guy and he said that's standard practice. They usually leave the smaller tire as a spare. Can anybody confirm that?

 

I bought my KR last week. It is the same, 20" on truck, 18" steel wheel as spare. I have also seen F150's on the road with a spare steel wheel in place of an aluminum wheel. Figured these guys had a flat recently.

 

My 06 FX4 has the same thing 20" Pirelli's with 18" spare

 

Same for my lariat

 

just picked up my fx4 today and saw the same thing.

 

It's cheaper for Ford. Most manufacturers do this. They have them same circumferance as the 20's.