When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My 98 Exp. has alum. wheels and the mating surfaces of the lugnuts are a flat washer, therefore they are not self centering. Why is different that the more common cone type lugnuts?
On cone type lug nuts, the lugnuts center the wheel. On later Fords the wheels are hub-centric where the hub centers the wheels, carries the weight, and the lugnuts just clamp it down and prevent it moving off the hub.
Aluminum wheels with steel cone/acron lugnuts tend to loosen up after a while. Also, hub-centric aluminum wheels with flat faced lug nuts do not need steel reinforcements around the stud area. Or something to that effect.