Most drivers don’t think about the lug nut until they have a flat tire. Considering that the lug nuts keeps the tires and rims on our vehicles during acceleration, braking, and turning, they are an important part of any vehicle. Pictured above on the right is an Original Equipment Manufacture (OEM) lug nut from my Toyota Tacoma. The one on the left is from a set of forged lug nut that I recently installed as a replacement. They may look the same on the surface but that is the only similarity. The image below is one of the OEM lug nuts that I cut in half.
The threaded part on the right is the actual lug nut. On the left is a sheet metal cap that is attached to the lug nut to improve the appearance. The problem is that over time the sheet metal cap will loosen and eventually fall off leaving you with a hex nut that is smaller than the lug wrench that came with your car. This damage is caused by over torquing the lug nut which stretches the sheet metal cap. Without the correct size socket wrench to match the hex head under the cap, there is a risk of stripping the OEM lug nut. Removing a stripped lug nut is very difficult and can easily cause damage to the rim.
Upgrading any vehicle with a set of good quality forged lug nuts, as well as torquing them to the vehicle manufacturer value, will help avoid problems down the road should you happen to experience a flat tire.