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Loose Lugnuts

Here’s the situation: Sometime last spring my husband rotated my tires for me. In early June, I noticed that the car was really loose, so I checked the tires. One of the tires was tilting back and forth when I pushed it, and the lugnuts came off with very little force. I figured maybe my husband had forgotten to tighten it up and it just took a while to get that loose. So, he got me a new tire (the threads on the rim had been hollowed out, so we couldn’t just tighten them back) and this time he made sure that he tightened the lugnuts. (He used an impact wrench.) So yesterday I was doing some driving on the interstate and it started to feel loose again. So, when I got home I checked, and the same wheel was not only loose, but three of the lugnuts had fallen off. What’s going on here? Is someone loosening them on purpose, or could there be something wrong with the car itself that’s causing this problem?



To add, both times it took about three months after putting on the tire before it was loose. But, I put a lot more miles on it the second time because I went on vacation shortly after we changed the tire in June. So, the first time it happened we probably put about 300 miles on it before the lugnuts got loose, but the second time we put more like 1300 miles on it.

Lug nuts should NOT be tightened with an impact wrench, ever.
The problem may be because of techniques, and/or worn out lug nuts, and studs.
You need to replace the lug nuts and studs with quality parts. I see too many metal products, which come out of China, which are sub-standard in strength and hardness. Make sure the replacements are NOT made in China.
Get your replacement lug nuts and studs from a non-chain store (which is likely to have them made in China). Dorman is one good brand. The dealer should have quality ones, also.
Hubby needs to get, and use, a torque wrench on those lug nuts. You really don’t want one of your wheels to pass you when you are driving 70 mph (it has happened), because the lug nuts were over-tightened, and they broke off. Happy, and safe, motoring.

The lugnuts were overtighten and stripped the studs. You need to get the car to a professional mechanic (not Walmart, or Sears, etc) and get all the studs on all 4 wheels checked and replacing them all would be best. Then get a new set of lug nuts and remount the tires using the proper torque with a hand held torque wrench.

I told him I thought he overtightened them! He tried to tell me that wasn’t possible.

It is quite possible and more than likely in this case. Tell hubby to put the air gun away.

In the interest of speed it is acceptable to turn the air down and snug the lug nuts up. After snugging, then they should be properly tightened instead of butchering the threads with excessive force.

Overtorqueing will also warp the rotors.

When lug nuts are overtightened the studs are overstretched to the point where they no longer hold tension. The “spring” has gone out of them. This is not necessarily apparent by looking at them. Once they are overstretched they must be replaced as others have already mentioned.

This overtightening applies to any stud or bolt, not just lug studs. Use a torque wrench.

You have our permission to slap him…use the torque wrench you are about to buy him.

Buy him a torque wrench and call it his anniversary gift.

Then, there are times when the lug nuts are tightened when the holes aren’t perfectly lined up and the wheel shifts a week later leaving you with loose lug nuts. There’s always something that COULD go wrong. The studs were probably damaged the first time you found the lug nuts loose and could have caused them to loosen again. What is a lug? It’s the part of the wheel that touches the nut and the area surrounding the nut.

He already has a torque wrench. I don’t know why he refuses to use it.