Tight lug nuts on my car

Hi guys,

I went to perform a brake inspection (and possible pad replacement, perhaps), on my 2003 WRX this Saturday. I started at the rear and when I went to take the driver’s side wheel off, I had to stand and bounce on the lug wrench each time to break all 5 of the nuts free. So, I go to the other side of the car and find the same thing… they’re all tight as hell. However, one of them starts to move, gives me a tight turn or two out, then stops. I stand on the wrench again to try and remove it and it won’t budge now… it’s frozen. I even tried to tighten it back on there, but it won’t move. I went ahead and tackled the front wheels with equal great effort, but I was able to get them free. The brakes are fine, but I do need to get that rear lug nut/bolt in order.

The last one to take that wheel off was the mechanic at a national chain tire shop that sold me some tires, and has subsequently rotated them. I’m positive that no one has touched those wheels since that shop. I think they over-tightened all of the nuts and stripped/cross-threaded that one in-particular.

The question… are they going to laugh at me when I tell them that they are responsible for this, and I want them to fix it?

Follow-up, how will it be fixed?

Thanks.

They used an impact wrench to put them back on, which is normal. If one was stripped, they should make good on it. It happened to me once.

Explaining to them nicely that you think they overtightened the nuts shouldn’t cause much alarm. Tell them the about problem you are having with one of them and see what they say.

Replacing a stud is a fairly easy exercise. I’ve done this myself. Total parts and labour, if they want to charge you would be under a hundred bucks I bet. Maybe Rick or Gary can chime in.

I’d be willing to bet that they’ll do it for free if you don’t come across as a frothing maniac.

Tire shop should do it for you, if they serviced it recently. On the other hand, if it’s been a while since they touched the car, they might want to charge you. Not sure about a Subaru, but fixing broken wheel studs is a fairly easy job on the cars I’ve worked on so it shouldn’t cost much. If you can work on your brakes yourself, you can change the stud.

I agree that you should go for a polite approach instead of immediately starting with the “they’re responsible for this and I want them to fix it” confrontational, accusatory approach.

It’s a virtual certainty that the shop in question overtightened the wheel nuts, and I think they should take responsibility here. They may or may not agree, they may or may not laugh about it. Whether they fix it for you depends on how seriously they take customer service combined with how accurately they assess their hand in this.

It’s a pretty safe bet that they used an impact wrench on too high a setting, which is all too common (I would not say “normal”). Now, if the nuts had been properly tightened rather than overtightened, it’s essentially a given that the one would not have seized like it did. But – here’s the rub – they’ve overtightened a jillion nuts without seeing any consequences and are likely to reason that they did nothing wrong. My armchair assessment here is they did wrong but they don’t believe they did wrong, and it’s probably nigh on impossible to prove to them that they did wrong.

I can’t tell from my repair info just how much work and expense it will take to fix it. It may largely depend on whether the lug nuts are replaceable separately or only as part of a hub assembly. Could range from 50-400.

Ask them to fix it. They may. If they decline, take them to court (good chance you’d win) or pay someone else to fix it.

I think it would be wise to replace all the lug nuts, as the threads have almost certainly been compromised.

In my tire shop there are times when some lug nuts are so tight even the pneumatic impact wrench won’t undo them. In this case I use this: http://www.walmart.com/ip/Torin-Jacks-Extendable-Lug-Wrench/14560053

It extends to twice the length and even the most stubborn lug nuts cannot resist to it. No need to use feet. Needles to say, I keep one in all of my family’s cars.

Also it helps if you pull upwards when loosening a nut instead of pushing downwards, you can put more power that way.

First I agree with ask the shop politely technique.

I have struggled getting lug nuts loose that I had properly tightened by hand some time back. It isn’t always that they have been over tightened, just a little corrosion.

To avoid that, I put a dab of antisieze on each stud and then tighten them up to 80% of dry spec. I have been doing this for years and never hjad any trouble.

Real mechanics have ways of getting anything loose besides a longer wrench. An air wrench hammering away sets up vibrations that can loosen the corrosion. For those of us that lack an air wrench or if it doesn’t do the job, a little penetrating oil and hammering on it often will do the job. There is always the ‘‘heat wrench’’. Heat it up with a torch and quench it. It is nearly always easier to use good technique than replace twisted off stuff. You may as well work at loosing something before twisting it off. You can always throw away a broken wheel stud and nut, but the bleed screw in a caliper is another matter.

Long wrench extensions aren’t so good, if you go over 3 feet or so, the risk of snapping off a stud is pretty high. One “soft” way is :

  • plenty of penetrating oil the day before
  • another good shot with the oil, then use a domestic vapor cleaner to heat the stud/nut (the floor/window cleaning kind), let it dry out and start over
    The 40-50° C differencial will often/sometimes be enough, and very little damage can be done. Hard steel has a dilataion of about 1mm/m/10°C, if you can access the assembly you can easily attain at least half a thread. It works best if you heat alternately the nut and the stud.
    If you do come down to whacking your tire iron, put it under tension, and hit it with fast “dry” hits, like an air wrench, using huge heavy sledghammer bangs will either break the stud or bend the wrench. Keep on with the oil, over and over, get it to penetrate, even a hairdryer works sometimes, don’t lose patience.

Tire garages are a pain, most of the time they have to undo their own nuts, air wrenches are set to max, and generally used both ways. Putting a bead of ordinary grease on any thread will always benifit correct torque but may dirty fingers, etc, pity. Also, pneumatic wrenches don’t look by themselves to see if a thread is fouled, but if set high enough they will certainly shoot the nut “home”

Be very polite and pleasant when asking at the shop.

If you’re nice about it, they’ll help you. If you’re rude, they’ll follow policy to the letter.

I’ve been in retail for over fifteen years. I (and most employees) bend over backwards to make pleasant customers happy–and if we can’t solve the problem, we’ll find a manager who can. If you make a fuss, 9 times out of 10, we’ll just say, “Sorry.” If you make a big pest of yourself, we’ll call management beforehand, and explain the situation, so you can’t even go over our head.

In the future I’d recommend not to “jump” on whatever wrench you’re using. A much better choice would be applying even/increasing pressure on a longer wrench, such as a breaker bar. You’ll lessen the chances of breaking the stud. Echoing previous comments I always use a lubricant of some type on each stud and then use a torque wrench to tighten the lugs at factory specs. A good shop will always do this vs. using an impact wrench. It never hurts to re-torque after a few miles.

Because I really don’t know, not because I’m being snarky…
But if you put oil on a stud and then tighten down the lug nut, isn’t the torque you’re reading incorrect?

The torque value you’re reading is the actual torque you’re applying to the bolt; that doesn’t change. What does change is the amount of preload (tension) that is developed in the stud as a result of that torque. This is why some folks, if lubing the threads, torque to a value below that spec’d in the manual.

The problem is that it’s difficult to know exactly how much you should reduce the torque; the relationship between preload (the tension established in the stud) and the tightening torque varies widely depending on exactly what sort of lubricant is used. Maybe you’ve nailed it, maybe you’re really close to the nuts backing themselves out, maybe you’re really close to overstretching a stud; you’ll never really be sure you’ve got a comfortable margin of safety since you’re no longer following a spec that’s been subjected to a whole lot of testing by the manufacturer.

It’s very rare that I let a shop remove/install wheels for me. When that happens I make it a point (the next time I get home) to loosen the lugnuts and tighten them myself to the proper torque with my torque wrench. If they’ve been overtightened by the shop, it’s easier to loosen them immediately afterwards rather than waiting 6 months or longer for corrosion to set in and make it even harder to break them loose.

It’s been my experience that lug nuts should be torqued to between 80 to 90 lbs. This varies with vehicle, but it sounds like yours were much tighter than that. Over torquing the lug nuts can lead to stripped threads that need to be replaced. Fortunately, this isn’t a major repair. I’d definitely mention it to the shop and see what they recommended.

So the bottom line is that it shouldn’t be done?

I, too, go home and re-do the lug nuts anytime someone else has my wheels off. And then I drive it for a day or so and re-torque before I bother to put the hubcaps back on.

Yes, the 80% I mention is likely something somebody pulled out of their butt. It does work for me and many others. Has it been tested? Not that I know of.

If you own a car, you get to set your own policy, but knowing what I know about engineering, screw threads, and product testing, I’m gonna stick with what the manual says.

W/regard to a lubricant on the studs, comments are noted. When required, I apply just a very thin coat of whatever I have handy, matbe just a drop or two at the end of each stud. It gets distributed as the lug is tightened. I don’t believe it’s enough to make that much of a difference. It’s more to just keep the stud from rusting.

The real bottom line is that in the real world, dry threads freeze up.

I’m a believer in cleaning them. I just clean up the threads with WD40 and a wire brush for the studs and a stiff bottle brush for the nuts. I clean off the excess with a rag, let 'em dry for a bit and then torque to spec. This has eliminated all of my nut-related problems, including on my stupid Isuzu which used to break at least one stud every time I so much as thought about taking the wheels off.