Lug Nut size?
 

I recently bought new wheels for my 1997 F-250. It is a standard cab, standard trim, 8' bed, 460 gas V8 model. The OEM steel wheels were starting to rust through and several wouldn't hold air.


The original lug nuts were flat bottomed. The new wheels need 60 degree conical ends. The wheel has 7 lugs.


According to just about all of the web sites I checked, I need 9/16" threads. However, when I purchased this size, the hole in them is way too large.


Any idea on what the size is supposed to be?


I plan on taking one of the nuts to a hardware store to see if I can find a bolt to match in order to discover the size, but if someone knows, that would save me a trip.


Thanks in advance!

My source says they are 12mm x 1.75

Yes, I took the lug nut to an auto parts store. They tried it on different sized studs till the found the correct size. It was 12mm x 1.75.