I bought a '99 F-350 that came on brand new 37's and aftermarket wheels, so of course they have the acorn lug nuts. I decided I don't want to put a lot of wear on these tires since I can re sell them to get some money back. I bought some stock tires / wheels, but they use a flat lug nut with the flange. Is it safe to drive this truck if I put the acorn lug nuts on the stock wheels?

I have them on right now but that was just to park it because where I park the 37's are too wide lol. This truck will pretty much just be taking things to the dumb or metal recycling, so maybe 50 miles or less a month.

 

No do not use the acorn style lug nuts on factory wheels. They will not properly clamp the wheel to the hub, risking a wheel off, and will eventually wallow out the hole for your stud to go through. You will need to get the flat torque retention lug nuts you mentioned.

 

Other than through Ford, where can I find factory lug nuts for 18" chrome XLT wheels? How do I know which lugs will work properly?