Lug Nuts "Turning/Sticking/Turning"
 

A 2009 Z51 coupe, 59k miles today.
Stock painted split-spoke wheels.
Factory lug nuts, lugs and nuts look clean. Never given any oil or anti-seize, but used brake cleaner (no resideue) on them once last year to remove any dust or dirt.
High quality torque wrench, less than a year old and never dropped.

Last winter on a very humid day in the 40's, everything in the garage was literally dripping wet with condensation. I'd had the wheels off and when I was torquing the lug nuts back on (star pattern 40/80/100 lb-ft), at about 85 lb-ft some of the nuts started a move-stick-move action as I was torquing them, like the metal was sticking or galling. I figured this was because of the condensation and didn't worry about it.

Now, 5 months/8k miles later, and after having the wheels on-off twice (tires), I experienced the same thing. About half of the lugs nuts are doing that move-stick-move thing starting around 85 lb-ft, that makes it difficult to get an accurate torque value and makes me wonder what's going on.

EDIT:
Torque values corrected.

Suggestions?

I know you must be doing it in increments because it's a 100ft lb torque. Any one ever run them on with an air gun or remove?
z51vett

Sounds like your studs are about to break off. I know a lot of people are against this, but if used wisely, a little oil will smooth things out and stop any breakage. You may want to reduce your torque a little.

Might have small amount of surface rust in the threads. Might try a new lug and see what it does.

FWIW I have never had that problem with my Gorrilla lugs. GL

Oil or anti-seize may help with the sticking, but it changes the torque setting. If the torque setting is given as dry, don't oil it and torque it, regardless of whether it's a lug nut, head stud, or whatever. Why? Because what's happening when you torque a fastener is you're stretching the bolt/stud. The torque spec, while measuring rotational torque, is really to ensure you stretch the fastener the right amount. If you use oil or any lubricant on something with a dry torque spec, you'll stretch the fastener more when you torque to the same spec. Bad idea. Trying to guess at how much to reduce the torque spec to stretch the fastener the same amount is a worse idea. There's no way to use any kind of lubricant "wisely" on a fastener with a dry torque spec.

I don't think the sticking the OP describes is because the studs are "about to break off," I think it's because there's some small amount of galling in the threads, either on the studs or inside the lug nuts.

OP, is this happening on all studs, or just some? If just some, inspect those closely, both the stud and the threads in the lug nuts for any dirt, debris, galling, etc.

Try a wire brush? I have a wire brush that mounts in an electric drill. I'd run that rascal on all the lug nuts in case there's rust in the grooves. I'd also use a battery brush on the inside of the lugs if they were showing dark threads. Sounds like some rust is forming and needs to be polished out of there.

Elmer

Clean STUDS with WD-40 and wipe off completely. Do not spray
WD -40 into lugs nuts. :flag::cool:

Were your wheels still in the air or did you have weight on them ?

:iagree:

We had a guy who posted last year about using some WD40 on his lugs and promptly snapped off two of them before ever getting to 100 lb-ft.

Unless your torque specs list some kind of thread lubricant, using it is an invitation to serious over-torquing. If you're going to do something that out-of-spec, why bother to use a torque wrench at all? Just use a long cheater bar and jump on it a few times.

Some people use thread lubes and have no problems.
My mother smoked two packs a day for most of her adult life and never had a problem.
I don't smoke and I don't use thread lubes, unless specified in the torque value.

I always hand-torque. I tell the dealership and tire shop to do the same, I think they do because I re-check after getting home and usually get just a very slight movement on a couple.

Wheels were in the air. Rears wouldn't move because of the trans/parking brake, fronts I use a wood wedge to keep them from spinning.

I'll try the wire brush trick and see if that helps. I also have a spare set of almost-new factory nuts, was hoping to save them but maybe this is the time to use 'em rather than just cleaning the originals.

I use anti-sieze on all the lugnuts on my vehicles. Been doing it over 25 years never had a problem.

Some people smoke their entire life and never get lung cancer. Doesn't mean either one is a good idea.

From one source on this topic: Arbitrarily changing the torque value 15%-25% by adding lubricant when it's not supposed to be there (or vice versa) is a bad idea, no matter how many times you've gotten away with it in the past.

:thumbs:

After 30+ years of dealing with galled threads and broken screws in my machine shop, I've come to the conclusion a dry thread is an unhappy thread. And also, it's almost impossible to relate this experience to others.

is it possible they are slightly ouf of round due to overtorquing by someone?

is it possible they are galling on the wheel? check for signs of unevenness on the face.

I couldn't agree more, machinist myself over 30 years. I've machine screw threads from triple lead acme to buttress to whitworth,pipe threads,metric even square threads.

You and the OP are the only one making any sense. :thumbs:

The two guys that claimed to have 30+ years in the trade are giving machinist a bad name.

Back in my past life of "Keeping Ships Fit To Fight", changing "dry install" to "lube install" fasteners will literally take an act of congress along with exhaustive testing prior approval for use. It was not a subject taken lightly due to the facts already covered by Steve_R.

That said, OP, after detail wire brushed, degreased, cleaned and blown dry, you need to take a real close look at the mating hardwares for abnormality. After verified having normal fit and finish, try by hand, switching known good lug nut on suspected stud and vice versa to form a base line. Do not use Gorilla brand, it is made in Taiwan with a poor reputation. On the other hand McGard is a better product with lifetime warranty, if going for aftermarket.

Most importantly, have your torque wrench check and calibration verified. Some SnapOn trucks have rechecking tool. Personally, I only use calibrated SnapOn or CDI torque wrench. SnapOn was used exclusively in Nuclear Power works for a good reason.

GL

:flag:

I agree. The automotive industry typically uses a "Factor of Safety" of 3. The airline industry uses 1.2 to 3 depending on the part.

So automotive wheel fasteners have something like a 300% safety factor built in and probably more because of the critical nature of keeping the wheels on. Meaning a 100 ft-lb fastener can take 300 ft-lbs before the load approaches the fasteners actual strength. A 10 to 20% over torque means nothing to a wheel lug or nut. Put anti-seize on it. Your threads will like it. And your threads will last longer than you.

http://en.wikipedia.org/wiki/Safety_factor

I would clean the studs and try a new set of lug nuts. There could be some deformation to the conical section of some of the nuts. Also, if the lug nuts were every over torqued (due to lubricant or whatever), the aluminum alloy wheel section that carries the clamping load of the lug nut could be galled, or deformed.

Question: if you leave the wheel off, and screw on the lug nut(s) by hand does the nut go nearly all the way down just by hand? If not, something is wrong with the stud or the nut.

Since GM wheels are hub centric, the hub shoulder carries the verticle load, not the wheel studs. So torquing the lug nuts on the ground or off the ground, should not make a difference as long as the wheel is flush with the hub bearing flange.

[QUOTE=victorf;1583830103]You and the OP are the only one making any sense. :thumbs:

The two guys that claimed to have 30+ years in the trade are giving machinist a bad name.



LMFAO!!!

Um, wrong, they're lug centric. But that's a whole 'nother discussion.

That guy who used some WD40 on his lugs and twisted off two of them before ever getting to 100 lb-ft, might disagree.

If someone would like to stop by my place and let me torque his wheels to 300, I'll supply the wrench and the beer.

:cheers:

You guys have outlined my next move.
Torque wrench is a CDI only a few months old, and agrees with my other older wrench, so I'm confident it's accurate.

I knew there was a reason I bought that extra set of lug nuts six years ago...

The drive for me to come watch is a bit far, so take video. Post it here. The amusement value will be epic. :rock:

Here comes another opinion. You said it happens when you get them almost torqued. I take it the nut is running down smooth till that point. To me that indicates the threads are ok. Look at the tapered seat area of the nut and the wheel. Those surfaces should be smooth, but I believe that is where you will find your galling and it is causing the dragging feeling you are getting. Hopefully its just on the nuts and your extra set will cure your problem.

Thanks, I'll check that also!

:iagree: Same here and never a problem, I use a LITTLE dab of Never Seize on the studs. Based on a recent post on the Forum, I called the Never Seize company and was told to reduce the torque by 20% when using their product. If you use some kind of anti seize compound you might want to check with them as to torque specs. One other thing, I don't use the "step" torquing process, just snug everything up and then torque to 80 ft. lbs. in a star pattern, good luck! :cheers:

"triple lead acme"?? "square threads"?? :confused: I am impressed, but WTF is that stuff? -from a non-machinist also named Don. :lol:

40 years for me, too. I always use a slight smear.:thumbs: But, then I am just an amateur, shade tree mechanic.

Gearhead, based on all your former postings, I am confident that you will use good tools to tackle this intelligently.

As member 42Chevy stated the possibility might be on the mating surface, that can be easily verify using very light blueing, or apply permanent marker on the taper sitting surface of the lug, sent it home, remove, then visual check the seating surface on the wheel.

Case in point, last Xmas, I took advantage of the discount w/free shipping from McGard, bought the McGard wheel lugs for my C6, noticed seating angle was a little different. Compared with stock lug with an Starrett Protractor, there was a 2* differential angle. So I blue checked stock and Mcgard lugs, they both share a contact band vary between 1/8" - 3/16". Further, both C6 and Honda shares the same wheel lock stock number and I am using wheel locks on my Honda. McGard wheel lock seating surface is conical instead of straight taper. So...evidently, contact for the torque draw is focused on very narrow contacting surface on each of the 5 lugs. Very interesting.

Please let us know how yours turned out.

:flag:

Just an FYI for those are interested, multiple leads used on screw thread is for fast engagement, Example: on fire hydrant cap, multiple lead is used to facilitate fireman's quick removal of the cap during fire rescues. To further improve multiple lead, simply milled off concentrically 180* from the beginning of the imperfect thread to ended up with an square corner for the start of the perfect thread - in essence, the combination will provide an bur free quick engagement without tiddies lining up of mating parts to avoid misalignment - as in the case during an fire rescue.

:flag:

I am an aerospace engineer who works on manned space flight hardware. I work with fasteners and torque specs all the time. While lug nuts and studs on a car are probably fairly forgiving, there is NO WAY that I would put lubricant, even WD40, on wheel lugs or studs.

Bad idea, I don't care how long you have been doing it.

Impressive resume, thanks for your post. Curious, can you tell me why you wouldn't use anything, thanks.

What's making the cracking is the seating surface, not the threads. Put a very small ammount of anti seize there if you wish. It's probably due to irregularities.

If it's the thread making the cracking, there might be something wrong. Had that problem with the Ford and I had to get some studs replaced.

The debate on whether or not you should lube your threads on Internet forums has been and will go on forever. I work on my own vehicles. I never have to fight rusted or corroded nuts and bolts. Nuff said, have a nice day.

http://i67.photobucket.com/albums/h3...CgarSmoker.gif

:iagree: 100%

If the spare set of lugnuts exhibit the same issues, then try a different wheel. It's certainly not the threads that are the problem, so the mating surfaces are the issue.

Make sure that both the lugnuts and wheels are free from any crud or flaking paint (as in the case of painted wheels) before installing.

I've had my wheels on and off well over 50 times just changing to DRs at the track. I'm on the 3rd set of lugnuts, but the OEM ones were the worst for imbedding crap.

There really is no debate, there's technically correct and incorrect. That said, for non-critical fasteners it probably doesn't matter a lot. However, if you use your approach for some internal engine and trans fasteners, ring gear bolts, and the like and ignore whether they're supposed to be torqued wet or dry you will learn a very expensive lesson the hard way. The more critical the fastener and components the more important it is. I've worked in the military and nuclear power fields, and if anyone ignored the wet or dry part of torque specs they'd be in huge trouble and probably unemployed. Same with working in aviation.

Feel free to keep posting that you know better and ignore the specs, but that just makes you look silly.

The reasons have already been stated. The loading of the fastener is totally different if the threads have been lubricated. As the owner's manual states, do not lubricate the threads.

That is not to say that thread lubricants are always bad. But in the case of lug studs and nuts, just say no.

Come on Steve, I agree to disagree. I'll keep anti-seize on my wheel studs and you keep them dry. This must be the only car forum you have ever been on if you say there is no debate on the subject.

It's kinda like debating whether my VY Vette is yellow. It can be debated, but there's only one right answer. :lol:

I think this guy knows what he's talking about. My vote: no lube. :thumbs:

Well said, another Nuke. :thumbs:

In my past life and back in the days, there were 700 strong well schooled machinist in the machine shop. Out of these 700 +s, will be 2 dz skimmed off the top from the pool and ultimately become Nuclear Machinist after extensive training and frequent requailifications. Then, Nuclear Toolmaker shop of 12 will maintain their workforce by skimming from the primo Nuke Machinist - one at a time. Anyone works in a machine shop can call himself a machinist - but like everything, there is machinist and there is Machinist.

I don't think some of the posters here came from that discipline. And if they did, they would've known better in regards to lubing on engineered dry install specimens.

Well, said.

Like there is a place and time for everything.

:flag:

---

Gearhead, if the culprit is the wheel side, you can easily make a simple jig with your stock lug nut by using two sided tape and emery to resurface the mating surface, using the wheel stud to maintain concentricity - like lapping a valve seat, just don't go hog wild with aggressive grits. Easy breezy after the root cause is found, that is. :thumbs:

:flag:

PROBLEM SOLVED

Combining several of the suggestions above, I did it this way:

Removed the nuts and wheels, then hand-spun each nut back onto the same stud it came off from. All 20 of them went on easily except for a few that got just a little sticky as they went into the "new" thread area that had never been used before, as they bottomed out. Even those ones took only a slight twist with my fingers. Threads on the studs looked clean and un-distorted with casual inspection.

Used a hand-held wire brush on the conical seating surface of each nut. Some of them had some some roughness or pitting. The brush didn't make them shiney-smooth, but they are better. I didn't have a brush for the inside of the nuts, but they looked very good.

Used a conical hand-held wire brush on the conical seating surfaces of each wheel hole. All of them looked slightly rough or scratched. The brush didn't make them shiney-smooth, but they are better.

Used a paint-safe brake cleaner on the wheel holes, studs, nuts, etc; then blew them thoroughly dry with the air gun.

After placing the wheels back on the studs, I used the air gun again to remove any flakes that might have been shaved off by the stud threads. Hand-installed the nuts, then torqued in a 40-80-100 star pattern.

All of the nuts went on smoothly, and all of them torqued smoothly to 100.

Thanks for all the help!

:cheers:

very interesting. I've read the whole thread. and clean but "dry.":cheers:

This fix will be temporary. Sorry.

Using steel wire brush on alloy conical seating surface is in reality, doing more harm than good. Aluminum alloy is soft by nature - existed condition was caused by original lug nut, probably mixed with foreign contaminants/or the alloy surface had bad finish, during torquing, dug into soft alloy seating surface and the sacrificial surface was the aluminum alloy, being the weakest link.

Certainly it will remove existing surface imperfections. However, under magnification, wire brushed area will certainly induced its own undesirable surface damages. Those damages will accelerate future problems with galling.

Long term fix should have been gradually restore seating surface, eliminate surface abnormality by using decreasing grade emery, then final polish to further reduce peaks and valleys, all the while maintaining seat mating angle. Further, ensuring all fastener mating surface are indeed positively free from contaminates prior to use.

Maybe some others following this can benefit from your experience. :thumbs:

:flag:

You could be correct. However-

I just looked at the seating surfaces for the nuts on my original factory wheels. They were installed when the car was made, never removed except about a year later they were taken off and stored in my indoors shop. The surfaces look about the same as the ones I just cleaned up.

If the problem returns, then I plan to use the method you suggested for resurfacing the seats. If it doesn't return, then I'll just keep motoring.

:cheers:

Jim, I'm sure it will be fine. It's a wheel and lugnut after all. Not precision machinery.

Running a die (like a tap) on the wheel stud threads every once in awhile will also help to keep them nice and clean.

Not sure off the top of my head what the correct size is though, sorry.

I don't know crap about this but it makes sense to me and I just removed all 4 wheels, cleaned them and wheel wells, brakes and anything else I could get to.
I used anti-seize when putting the wheels back on, I personally think its a good idea :yesnod:
NSF

:iagree: never had a problem.

:iagree: I cant agree more.

Same here....cept been doing it for about 40 years. And in all that time I have never heard the term "Dry Torque" and I have torqued a whole lot of nuts & bolts. Some of them probably had some kind of lube on them also. Considering the actual physics involved in torque, which is simply the amount of clamping and/or stretching force involved usually created by two angled surfaces (screws...etc.) twisting against each other, I would love to hear how lubrication changes these values ? I understand that lubrication makes it easier to extend/overrun the values....but how does lube change the actual torque ??