the rims run different profiles. Aka the height of a tire. so if you re looking at tire sizes you will see: 265/35/19. The 265 refers to the width of the tire, the 35 refers to profile, and the 19 refers to inches of the rim. The 19 inch wheels have lower profiles. Therefor, they are close in size but the 18 inch has extra tire instead of the extra inch of rim. Let me know if you have any other questions. I was like you when I first joined this forum. Search around and you will learn A LOT!
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