[cboyfan2020]

probably a lot. in order to have the speedo work properly you have too "plus size the tires".Say your truck came stock with 265/70/16...then you want to change to 17" rims...tires would need to be 275/65/17 to acheice the same overall diameter.. Can affect speedo, abs, and handling....Not sure but some power chips will aloow you to reconfigure the ecm to accept the new size but not sure.