Procedure for taking off broken, rusted hub stud?


I broke one of the wheel/hub studs on my 2006 Ford Focus, when I tried to take the wheel off. So, this car lived through 7 winters in Boston metropolitan area, and it has about 90,000 miles on it.

I bought the car used last summer, so I don’t know what the previous owner did, but I have always torqued my wheels since I bought it. But one of them broke off anyway, when I tried to take the wheel off. I took off the brake caliper and the disc to see the condition of the broken stud. The hub and the stud seemed to have rusted together. I recently moved from California via Oregon, so I am not used to seeing a lot of rust on anything. So, I can’t tell whether that is a lot of rust or just normal run-of-the-mill rust I shouldn’t have to worry too much about.

I checked online and found that if a bolt/stud is rusted, and if I cannot get it loose by banging it with a hammer, I should torch it and let it cool before trying to loosen it again.

I know that no one can advise me on how much trouble this would be, especially without seeing it. But I would like to hear some anecdotes about loosening wheel studs. I went to Harbor Freight today to get a hammer. One guy told me I should get the 8 pounder with a long handle (looked to be 3 feet or longer), so it will be easier to aim and provide steady force. He said it would be like putting a golf ball. I was also looking to get a torch, and he said that I need to heat it until it glowed, so small propane bottle torch would not be enough. But he said for a relatively newer car like mine, a few taps with an 8-pound sledge hammer should be enough.

I am also concerned that I might end up breaking more stuff and have to replace the entire hub, which would be a costly proposition. How much would it cost if I took it to a mechanic?

Also, seeing that some of the other nuts didn’t go in smoothly, would it do any good to replace all the lug nuts? A set of 16 costs about $15 on eBay.

Thank you.


Roger, from reading your post, I think you’d be money and time ahead to have a pro do this for you. This is probably going to require special tools and techniques. Banging it with a hammer will likely do more harm than good. Either contact a local inde shop for help, or an auto machine shop. They do this kind of thing every day. Some thing syou can do yourself, and some, well you might could, but you’re better off in the long run to let someone else do it, someone who does it all the time. I doubt it would cost much just for one stud. Are you able to get the car to a shop yourself, or would you have to have it towed? If towed, the towing fee will probably be the biggest expense.

I think I needed to hear from one of you experienced guys that I should take it to a shop. I will take it to a shop on Monday. As long as I drive slowly, I should be able to drive a couple of miles with only 3 of the 4 lug nuts.

How much do you think it would cost?

Also, do you think it’s a good preventative measure to change all the lug nuts?

Thank you.

Sometimes it takes a punch and a very heavy hammer to punch out the broken off rusted wheel stud.

But what you to look at if there’s enough room behind the hub flange to insert and draw in the new wheel stud. Remember, the broken stud is shorter, but the new stud will be longer.


I don’t know how much it would cost. But I wouldn’t expect it to cost very much. If they say more than $150, I’d look for another shop. I guess I’d expect it to be more like $75. Me, I’m on cheap side, so I wouldn’t replace any of the other ones unless there was visible damage. One thing you can do is spread a little grease on these studs which will offer them some protection from further rust problems. I always spread a little moly on the studs whenever I take a wheel off. It also helps prevent the lug nut from sticking so tight you can’t get it off with a lug nut wrench, and making it impossible to change a flat tire on the road. If you phoned a machine shop, I’ll bet they could give you an estimate for this over the phone. It’s a very common repair for them. Best of luck.


Wheel lug nuts/studs are a dry torque application. Notice how new cars don’t have any lubricants on the nuts/studs?

The reason is, the wheels are removed from a vehicle many times for different services. If you apply a lubricant to these dry torque fasteners it results to over torqing of the dry torque fasteners. Over time this over torquing will stretch the wheel studs to the point of failure.


Well, I learned something today. Thanks Tester. Maybe 20 and 40 year old cars aren’t as sensitive to this as newer cars. I’ve done it for 40 years and never had a problem myself. I always use a hand torque wrench. Maybe the air driven ones like they use in the tire shops are more problematic.

Hammering on a wheel stud in a hub in place is not good for wheel bearings if that was done; can Brinnell them that can precipitate a bearing failure. You might want to remove the hub and have the stud pressed out with something like a 10 or 20 ton hydraulic press. That can be used to press in a new stud as well. A little penetrating oil on the stud will help. If one is done, it’s little additional work to do all.

If someone comes into my shop with a lubricant on the nuts/studs that requires that I remove and reinstall the wheel, I won’t touch the vehicle. I don’t like getting sued if a wheel falls off after it leaves my shop.


What do you think about this technique I use for lug nut tightening @Tester? I do all the work on my 20 year old car and 40 year old truck that I can, but I don’t have the equipment to mount tires. So I have to have that done at a tire shop when I buy new tires. But as soon as I get home with new tires installed, I park the car and loosen all the lug nuts. The first thing I notice is that there is a considerable difference in how tight one lug nut is to the next. And one wheel to another. I notice that some of the lug nuts are on much tighter than the others, even two on the same wheel. I don’t have an explanation, but I almost always experience this when a shop tightens the lug nuts with their air tool. Some are on so tight I can barely get them to loosen unless I get out a 1/2 inch drive breaker bar and socket. Sometimes I have to almost stand on the end of the breaker bar to get it to come loose. Anyway, once they are all loose, then I jack up the vehicle, and retighten the lug nuts with my hand held torque wrench (after putting a very thin layer of moly on the lug threads). I increase the torque incrementally, not all at once. I tighten to less torque than what I want to end up with, in a star pattern, alternating across the hub, first with the wheel off the ground, to insure the wheel is centered, and later with the wheel on the ground. It takes me about 10 minutes per wheel to tighten the lug nuts. Then I drive the car around the block, and recheck the torque and tighten as needed. I check the torque again after a week of my commuter driving.

Like I say, I’ve never had a problem when I do it this way. Never had a lug nut become stuck on so tight so I couldn’t change a flat. Never had a broken stud. Never had a lug nut fail to conform to the lug threads or strip the threads. Never had a tire come loose or fall off when I tighten the lug nuts this way. Never had a severely rusted stud. So that’s the upside. The downside is that it takes me the better part of an hour to tighten the lug nuts on all four wheels.

I can see your point of view too, since the lug nut torque is spec’d for a dry fastener, you can’t put lube on the stud threads of your customer cars. But what do you do if the stud is really rusty or dirty? Do you clean it off with a wire brush or something? I’d think the resulting torque you’d end up with would be wrong on the other side of the equation if the stud was dirty or rusty. It might measure the correct torque, but would actually not be on tight as it should be because the nut is experience so much friction on the stud threads.

It’s a fun interesting discussion anyway. I guess when actual practice grinds up against theory, that’s when things become interesting!


What you do with your vehicle is up to you. But if you were to bring your vehicle to me for service, and if I saw lube on the lug studs/nuts that required me to remove/reinstall the wheels I won’t do it. Because when I use my torque wrench to tighten the lug nuts I don’t know how many FT/LB’s to set the torque wrench at. Because with lube on the hardware it’s going to cause over-torquing. These are dry torque fasteners. If they weren’t, not only would you have a spare tire, jack, and lug wrench, but also a little bottle of oil to lube the lug studs in the trunk. So if your lug studs fail from over-torquing and you try to point your finger at someone, there’s going to be three fingers pointing back at you.

As to why the lug nuts are tighter than others I can’t say. I don’t know what method your shop is using the tighten the lug nuts.

When I install wheels/tires, I run the lug nuts down with a cheap 9 volt impact gun. This impact gun puts out only 50 FT/LBs max. Then I lower the vehicle and finish tightening the lug nuts to their spec with a clicker type torque wrench.

As to stubborn lug nuts? I have an impact gun that puts out 1,000 FT/LB’s. So either the lug nut is coming off or the stud is going to snap off. Better to find this out while the vehicle is in the shop, rather than trying to change a flat tire on the side of the freeway during a pouring rain while semi’s scream past your butt.


I am the original poster. It seems like the thread took a very interesting turn. I like this discussion. Never mind my problem. I am taking the car to a mechanic tomorrow.

About torque on the lug nuts, I was told it is a dry torque spec. This means, the given specification is for tightening it without any lubrication on the threads.

I agree with TESTER that lubricating the threads, then tightening it to the same spec would over tighten it. However, technically, it is not over-torquing it. What is really is over-tightening it. When the lug nuts are tightened, the threads on the nut and the threads on the studs rub against each other and create resistence along with the friction caused by the face of the lug nut and the wheel. However, if there is lubricant on the threads, there would be less resistance from the threads and the surfaces, so the lug nut would turn a little more than if the lug nut were tightened without lubrication. But in both cases, the nut would stop turning when it reaches the specified torque. Put it in another way, the lug nut would have pulled/stretched the stud more if there were lubrication. This would be dangerous, which could cause premature failure–meaning breaking the stud. So, TESTER would not want to deal with such a car.

Then, the next quesiton is what do you need to do, if you want to lubricate the threads. It is common sense that lubricated threads would require less torque to pull the same amount. So, you would need to reduce the torque, if you want to lubricate. I was told the dry torque spec would have to be reduced by 20% or more if it is lubricated. You would have to do research to find out exactly how much. But this could cause a serious problem. With less torque (or friction, depending on the perspective) between the lug nuts and the studs, the wheels could come off. Is it the right wheels or the left wheels that are tightened backwards in military vehicles? The reason one side of the vehicle is tightened backwards is to prevent the wheels from coming off due to normal driving. For example, my car Ford Focus calls for 100 ft-lb of torque, but if I lubricate the threads, I would need to tighten them to 80 ft-lb or even less, depending on what type of lubrication I used.

Reducing the torque spec would be perfectly fine for stationary application. For example, if I have an outdoor structure that is not subject to vibration (such as people stepping on it repeatedly, swaying in the winds, etc.) and I am worried about the bolts rusting, I would lubricate the threads and reduce the torque accordingly. This is perfectly fine, because reduced torque when lubricated would provide exactly the same amount of force that pulls the two pieces of material together. So, if you lubricate and reduce the torque on the wheel lug nuts, the force that pulls the wheel to the hub would remain the same, but the friction between the threads and the friction between the bolt sufrace and the wheel would decrease. This would increase the possibility of the wheel coming loose when subject to vibration–such as driving the car. So, I agree with TESTER that lug nuts and studs should not be lubricated.

Another important issue is that the threads on the nut and the stud need to be clean. This is common sense, because any dirt trapped in the threads would increase friction, which would provide less pulling force at a given torque. So, I would clean the threads without lubricating them.

How great is the danger from lubricating the threads and torquing the nut to the dry torque spec? I agree that there is danger, but I am not sure how dangerous it may be. From the automotive engineers point of view, these stuff must be designed to withstand fair amount of abuse. Until 10 or 20 years ago, not many people used torque wrenches to tighten wheel lugs. They just tightened them with impact wrenches. I am hesitant to guess what the possible torque that might be, but greater than 150 ft-lb is not unimaginable, when most cars call for 90 ft-lb to 120 ft-lb for the lug nuts. So, if GEORGESANJOSE lubricates the threads (lightly as he says) and torques them, the pulling force on the studs may be equivalent to dry torquing it to 120ft-lb to 130ft-lb, which would definitely too much according to the manual, but I would guess it probably is within the design spec of the manufacturer. I am not saying I agree with GEORGESANJOE in lubricating the threds. But what I am saying is that it probably is safe. Well, he hasn’t had any trouble so far. I guess the problem is in not knowing all the facts. Car manufacturer will not tell you that 100 ft-lb is the ideal torque for the wheels, but they are perfectly safe to torque to 150 ft-lb. They will only tell you what the specified torque is. So, GEORGESANJOSE is treading unknown territory when he lubricates the threads, then torques it to dry spec.

About rust on the wheel studs. I recently moved from the west coast where rust is unheard of. There, I had never experienced any stubborn lug nuts or rusted nuts. Only when I moved to Boston, I experienced rusted wheel studs. I bought a set of winter tires, so this is my second time taking all the wheels off and putting another set on. Like GEORGESANJOSE said, I torqued all the lug nuts, but when I tried to take them off a few months later, some of them were extremely tight… In fact, one of them broke off.

In conclusion, I agree with GEORGESANJOSE’s method of putting on the lug nuts, except lubricating them. I think the owner’s manual also calls for checking the torque after driving a few miles, especially for aluminum wheels. I recheck the wheel lug nut torque the next day (after a round trip commute). Last fall, a couple out of the 16 lug nuts tightened a little more the next day. So, I think it is extremely important to check the tightness of the lug nuts after the initial installation.

All of the discussion in this thread is ignoring a couple of things: Some of the tightening torque applied to a lug nut is not thread friction but is friction between the tapered surfaces on the lugnut and around the wheel stud holes. No comment about lubrication or lack of it on these surfaces was made. They also are intended to be dry as there is no lubricant on them that arrives with a new car. In addition, fears of snapping a stud due to excessive tension in the stud due to lubrication applied to the thread and the tapers can be alleviated by degreasing the parts.

Who knew lug nuts could be so complicated? I agree it’s an interestng discussion. Good on you all for contributing. I wonder if anyone out there has sat down, thought it out, done the experiment and measurements, and come up w/the optimum technique for re-installing wheels on used vehicles. It seems unlikely the best thing to do is to do nothing, just put the nuts on the studs as they are and torque them to spec. Dirt and rust would result in an imprecise holding force. And w/no anti-rust coating at all on the studs, you are looking at the possibility of the stud rusting to the point of being unusable and possibly breaking off.

I’m wondering if the optimum thing to do is to clean & degrease the studs and lug nut and threads as best you can, along with the mating surfaces on the wheel, dry torque them, and afterward apply anti-rust protection?

Re wha who’s comment, no, I don’t lubricate the wheel mating surface or the lug nuts. You may be right that the actual resulting torque value is more the result of the friction between the lug nut outer surface and the wheel more than the lug nut interior threads to the stud.

I find it hard to believe that manufacturers buy 1/2inch(?) lugs that can be over torgue by using a 10"-14" wrench. There is soft steel and then there is crystalize steel.

I used to spray a little WD-40 or similar on the threads when tightening the lug nuts on my first few cars. Not copious amounts, just enough to keep them turning smoothly. Keep in mind that these were cars that were old, rusty, and others had pretty much thrown away. This was simple insurance that the nuts wouldn’t seize and cause me problems. I also never used a torque wrench on them, but just guesstimated the torque when tightening them.

I also never cross-threaded one, never broke a stud, never had one loosen up and needed to be re-tightened, and if the studs stretched any, I never noticed it. They were also on cars that were 5-bolt rims, old, sturdy American iron too. Not sure if I could have gotten away with this on a 4-bolt CVCC or similar…

I’m thinking that oiling the threads has nothing to do with tightning or loosening of wheel nuts or any nuts off the tree. It’s the friction from of the nut against the wheel than insures the nut staying tight. The threads gives you leverage to tightened the nut,

Why is it you never place a lock washer on the headside of a bolt? If you can give a good answer to this, I think we have solved this riddle.