A lug nut is a metal fastener that secures and positions a wheel on a vehicle. It can become swollen over time due to moisture and corrosion. Swollen lug nuts can become difficult to remove using standard tools. You might not be able to change a flat tire if you have a swollen lug nut, and that’s a situation you don’t ever want to find yourself in.
Find out about the dangers of swollen lug nuts and why you should replace them as soon as possible.
Two-piece lug nuts are nice and shiny because they’re made from two kinds of metal. Steel is used to make the lug nut. Then a chrome sheet metal covering is added to make it shine. Rust can form in between the two layers of dissimilar metals over time, causing them to expand and warp.
The lug nut on the left is an example of a normal lug nut, while the one on the right is an example of a swollen lug nut. Swollen lug nuts tend to look rusty, warped, or scuffed from being taken on and off.
Steel can corrode and push against the nut’s chrome cover, causing it to enlarge. This can happen naturally through galvanic corrosion. When two dissimilar metals are exposed to one common electrolyte, one of the metals can corrode. Force can also accelerate the swelling of a lug nut. Removing lug nuts with cheap impact sockets can cause the top chrome layer to loosen and create an opening for water, salt, and corrosion. This problem is prevalent in some Jeep, Toyota, Ford, Chrysler, and Dodge models.
As an example, a twenty-one-millimeter lug nut can grow to twenty-two millimeters when it swells. This becomes a problem when you have to change tires on the fly and your lug wrench doesn’t fit around the nut anymore. Severe corrosion can cause the chrome cover to fall off and expose the steel nut underneath. You can end up stranded on the side of the road if you can’t remove the lug nuts to change a flat tire.
A standard lug wrench might not be enough to remove a swollen lug nut. To avoid damaging the wheel, we recommend asking your mechanic to remove the lug nut for you. They have the tools and know-how to extract this part safely.
Lug nuts are designed to last the life of the vehicle, but they can fail prematurely due to rust and swelling. You’ll want to replace swollen or damaged lug nuts as soon as possible.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.
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My daughter encountered the 'swollen lug nut' issue when replacing the tires on her 2019 Pathfinder at Costco Another disappointing flaw from the auto industry. Nissan will ungraciously replace them for $13 each. Costco, has ordered them for her at about $1.50 each. Another good reason to avoid dealerships.
Ford don't care no more, just another reason to buy something else somewhere else. Fhat Jim Farley needs do get de boot 👢 as soon as possible. IMO.