Shows about a 20% (using 9/16" as representative od a standard lug)difference in torque required to create bolt loads dry vs. lubed. There is a similar table in the Machinist Handbook.
I can't believe a 500% diference in the real world. Maybe in the lab with exotics...
BTW - if you have ever rebuilt a european engine, the torque specs call for an initial torque (ALWAYS Lubricated) and then using a bolt stretch guage to measure how much rotational stretch the head bolt has.
BTW2 - this is my opinion, derived from real world experience building BMWs and Toyota 4x4s.
And FYI - On my trucks I use anti-seize on EVERYTHING except special bolts like bleeders an banjo nuts. On cars, any suspension part and any external (not inside the oil lubricated spaces) that has steel bolts going into aluminum.
This thread has made for some real interesting reading! Most torque specs that I've come across are "dry torque" specs. This would suggest that in order for you to torque something to the correct spec, the threads must be dry. With this thought in mind and a couple of minutes on the Internet...
B) McGard does not recommend the use of oil, grease or anti-seize lubricants on threads. Spraying the threads with a greaseless lubricant (such as LPS-1) once a year is recommended.
How come they never lubricate the lug nuts on my wheels? Wouldn't that make them easier to take off when I change a tire?
Lug nuts or studs should never be lubricated. While it may make them easier to remove, they could come off while you're driving. If you can't remove them with the equipment in your vehicle, call the GM Roadside Assistance line provided in your Owner's Manual.
While I don't think Mr. Goodwrench is the last word on automotive info I do think that a lug nut manufacturer would have some valuable info. Now I wonder what LPS-1 is? Have to do another Internet search.
Try putting it through a piece of steel. Make sure it fits the hole quite well, use hard (grade 8) washers under the head and the nut, and make sure the mating surfaces are flat and burr-free. Make sure the bolt is only slightly longer than necessary, perhaps two threads or so.
Then, use a micrometer to measure the length of the bolt at a given tightening torque on the nut. Lubricate the threads and do it again. The additional stretch of the bolt with the lubricant on the threads is a sign of additional tensile stress on the bolt.
DJ,
Wouldn't a control group be better, one without antiseize and one with? I'm wondering that tightening the same bolt dry, then re-torquing with lube would be streaching the same bolt twice. Yes, no?
RE
__________________
Great Apes are not great......they're just big gay monkeys.
LPS-1 is a lot like WD-40. Does about the same thing but the recipe is a bit different.
While I still put some kind of lube or rust preventative on just about every fastener I put in (even it's just once over the life of the fastener), it's definitely true that if the faster DOES manage to come loose because you didn't tighten if enough it's going to go from loose to off a whole lot faster if the threats are "wet" vs dry.
When I put anti-seize on my lug nuts I'll pretty much wipe as much out of the male thread as I can so it's just a film and I'll often thin it down even more with WD-40 on the female side. I'd use just WD but the film strength isn't enough to last for, say, 5 years; so that's why I use a very light coat of anti-sieze to supplement.
I've personally never had an issue - ever - so I'll keep doing it until I see an actual result that contradicts my practice. I've way over a million miles I've driven on my vehicles and I'm working on the 2 million mark next.
I could be like the 90 year old guy that's still smoking cigarette's though: "well, if it's not killed me yet......". But most of the people I know that lube threads just keep on doing it forever.
To me there just isn't any reason to break a fastener no matter how long it's been in. (And I've got a van that's going on 32 years of driving and has been around the USA twice.)
Alan
Quote:
Originally Posted by mdbrjb
This thread has made for some real interesting reading! Most torque specs that I've come across are "dry torque" specs. This would suggest that in order for you to torque something to the correct spec, the threads must be dry. With this thought in mind and a couple of minutes on the Internet...
B) McGard does not recommend the use of oil, grease or anti-seize lubricants on threads. Spraying the threads with a greaseless lubricant (such as LPS-1) once a year is recommended.
How come they never lubricate the lug nuts on my wheels? Wouldn't that make them easier to take off when I change a tire?
Lug nuts or studs should never be lubricated. While it may make them easier to remove, they could come off while you're driving. If you can't remove them with the equipment in your vehicle, call the GM Roadside Assistance line provided in your Owner's Manual.
While I don't think Mr. Goodwrench is the last word on automotive info I do think that a lug nut manufacturer would have some valuable info. Now I wonder what LPS-1 is? Have to do another Internet search.
Alan, it does sound like what you have been doing is a good compromise. If the threads are just about dry, then it should be possible to achieve the correct torque.
I think companies are afraid of the guy that would use a grease gun on the lugs!
DJ,
Wouldn't a control group be better, one without antiseize and one with? I'm wondering that tightening the same bolt dry, then re-torquing with lube would be streaching the same bolt twice. Yes, no?
RE
The intent was two-fold: 1) to remove the variable of one bolt vs. another bolt, and thereby find the additional elongation due only to the use of lube; and 2) to stress the bolt in its elastic range so no permanent deformation occurred. If you re-read my post concerning my test, you'll see that I re-checked the length of the bolt after slacking off the nut with dry threads, and the relaxed length didn't change, which means there was no measured deformation of the bolt.
The overall test should be repeatable with the same bolt using a degreaser (such as Birchwood Casey Gun Scrubber) to remove all traces of lube between tests. But, I've not attempted that.
i did wheels and tires for 7 years. used anti sieze and hand torqued all studs. tens of thousands later and i NEVER had one loosen, never warped a rotor! anti sieze reduces the amount of torque needed to obtain the correct fastener tension so if i was worried about a fastener being questionable i would reduced torque by 10%. they are much more likely to loosen if you torque to factory specs with rust on the threads and there is a good chance you will cross thread it going on or the poor sucker that takes it off will look like a jerk when it breaks! a 12mm toyota wheel stud wont break unless you apply well over 500lb/ft. it wont even stress or strech too much at 200lb/ft. dont worry about it and lube them up!
BTW - For those who say use silicone or other dry lubricants: some of the table I looked up had torque values for dry film - it also modifies torque required to create the clamping pressure. (and some tables show differences for plating too -CAD plating has a significant effect...)
And mods - lame to move the thread without posting the fact that you did so - but its your site....
I think I've drawn some conclusions based on this thread. TLCObsession's last message kind of sums it up. Clamping force.
The manufacturer specifies a certain required torque to achieve a specific clamping pressure. This torque specification is based on clean dry threads. Therefore, anything on the threads will change the clamping force based on the torque spec. Dirt, rust, oil, silicon, anti-seize will all change the clamping force at a specific torque.
Now I suppose that if you knew how much to modify the torque setting to compensate for the dirt, rust, oil, silicon, etc. you could achieve the correct clamping force.
So, I guess I'll try to keep the threads clean and dry so that the specified torque achieves, as close as possible, the correct amount of clamping force.
OUTSTANDING thread, one and all. Major appreciation to both DJ and akauth for presenting both sides of a clearly contentious topic.
I have no doubt that the wheel studs that Toyota uses are good ones but having broken several trying to remove wheels before (the local toyota place really screwed the pooch putting them on with an airgun), I'm pretty sure they'll break well before the 500ft-lb range...I was using a 100ft-lb torque wrench (S&K beam type so the cal isn't subject to unnoticed change) and they were popping at around the 95-100 ft-lb range.
If it's something you've done for ages with no issues, by all means continue to follow the practice...but I think we all agree that the manufacturer selects lubed torque values at a different level than unlubed and that a lubed bolt is much easier to break than an unlubed one.
I've talked to experienced mechanics that tell me a wheel stud shouldn't break at even 200ft-lbs, but based on how easily I was able to break a total of 3 studs I don't think I'll chance using up the margin built into the spec. (I gave up after that and took it back to the dealer that did the work...they never made any noise about trying to charge me for replacing ALL the wheelstuds...even the unbroken ones...after I mentioned the possiblity of Toyota wide defective studs)
I think I've drawn some conclusions based on this thread. TLCObsession's last message kind of sums it up. Clamping force.
The manufacturer specifies a certain required torque to achieve a specific clamping pressure. This torque specification is based on clean dry threads. Therefore, anything on the threads will change the clamping force based on the torque spec. Dirt, rust, oil, silicon, anti-seize will all change the clamping force at a specific torque.
Now I suppose that if you knew how much to modify the torque setting to compensate for the dirt, rust, oil, silicon, etc. you could achieve the correct clamping force.
So, I guess I'll try to keep the threads clean and dry so that the specified torque achieves, as close as possible, the correct amount of clamping force.
OUTSTANDING thread, one and all. Major appreciation to both DJ and akauth for presenting both sides of a clearly contentious topic.
I have no doubt that the wheel studs that Toyota uses are good ones but having broken several trying to remove wheels before (the local toyota place really screwed the pooch putting them on with an airgun), I'm pretty sure they'll break well before the 500ft-lb range...I was using a 100ft-lb torque wrench (S&K beam type so the cal isn't subject to unnoticed change) and they were popping at around the 95-100 ft-lb range.
If it's something you've done for ages with no issues, by all means continue to follow the practice...but I think we all agree that the manufacturer selects lubed torque values at a different level than unlubed and that a lubed bolt is much easier to break than an unlubed one.
I've talked to experienced mechanics that tell me a wheel stud shouldn't break at even 200ft-lbs, but based on how easily I was able to break a total of 3 studs I don't think I'll chance using up the margin built into the spec. (I gave up after that and took it back to the dealer that did the work...they never made any noise about trying to charge me for replacing ALL the wheelstuds...even the unbroken ones...after I mentioned the possiblity of Toyota wide defective studs)
if they have been overtorqued in the past they have been permanantly streched, dramatically weakened and will break much easier. 100lb/ft sure isnt going to do any harm, its the guys that hammer then on with an impact at 200lb/ft+ that are doing the damage!
Alan, it does sound like what you have been doing is a good compromise. If the threads are just about dry, then it should be possible to achieve the correct torque.
I think companies are afraid of the guy that would use a grease gun on the lugs!
Actually, you've hit the nail on the head (sorry to use the old cliche but it applies). If you're an idiot about it and you goop the stuff on then put the lugs on then I rather suspect you'll be pretty sorry with what may happen.
And I categorically and emphatically AM NOT recommending that anyone goop a lot on!!
It's going to take a lot of pressure just to squeeze the excess out due to the high fluid viscosity if you put too much on. Also an engineer has to specify for complete boneheads to be doing things. I mean, there are lawsuits where people lift running lawn mowers to trim bushes - what kind of an idiot?????
It's actually been a couple of years since I pulled my wheels off this time. I just did my brakes. I had the retrofit calipers put on at something like 27,000 miles and I pretty much ran them down to to something you can barely measure at 90,000 miles. I think the toyota tech left air in the lines and that's why they lasted so long. I always thought the replacement brakes were softer than the OEM brakes, but I think they didn't bleed them right. I had a surprising amount of air in both front line. In fact, I thought I was screwing up there was so much air.
I bought all new hardware front and back so the brakes will be back to factory spec without turning since the rotors and drums will be brand new. I've been so busy the past two years that I've been really bad about even rotating the tires. I'll have an oil analysis coming on my redine oil with 17,000 miles on it. Curious on what the TBN is - I didn't freshen it up or change the filter even. That's pushing it, but it's great oil. I just took it to the edge. I'll see how close I got.
I was quite surprised at the condition of the wheel studs. Of course, they were like new and I measured the torque to loosen the bolts and it was still exactly at the 83 ft lbs that I put them on with. That's after at least 20,000 mile and I'm embarrassed to say, probably a whole lot more on top of that.
But to be honest, other than being in great condition, you couldn't really tell that they had ever been lubed. They were just perfectly clean and in fact they even looked pretty dry but with zero oxidation. I just filled/sprayed the lugs with some liquid wrench, dumped the excess out on a paper towel and put the lugs back on a couple of times to spread the lube. I'm pretty satisfied that they came off 20,000 mile later in exactly the same condition and torque that they went on.
I don't go crazy with lube though. I put the bare minimum on to cover the threads and will even wipe off excess with a paper towel so that lube only remains in the valleys and spread once you've put it on a couple of times with a little WD40 to thin it out. The WD40 does dry out of the joint over time due to the heat.
On one hand, I understand the thought behind no lube - then you have to specify what KIND of lube in specing your fasteners - what a headache!!! If you don't spec lube you totally avoid that issue.
I've been using light lube (WD-40 or the equivalent) on threads for so long and they come off in exactly the same condition and torque I put them on with. I've even applied anti-sieze to "semi-dry" levels and I've never seen an issue. Bolts have always "cracked" off the same, it's just that nothing ever breaks and the threads are like the day they were made.
One of my vans is 35 years old and has been around the US twice camping and I highly doubt that many of the bolts would not be frozen solid if I had not applied lube to them 20 years ago. It makes a difference!!!!
The only thing I've never applies lube to is brake bleeders since you can't contaminate the fluid.
If you're not going to be in it for the long haul, it probably doesn't matter. Someone else is going to be breaking those bolts/screws and having to fix them.
But if you are in it for the long run, then it makes a difference. You don't break stuff merely getting it loose - not even 20 years later. If you don't go to the high end of the torque range but stay within it, you should have the same success I've had over the year both in time and hundreds of thousands of mile. Fortunately, a little lube goes a long way.
And I'd rather have my fasteners be a little overly tight due to lube (I've *never* broken one) than rusted since rust (if it's bad enough) is going to weaken fastener material also. While a rusted bolt might meet torque specs, it's not truly as tight as it should be if the rust on the threads is causing the readings to be higher than they really are.
But again, you use minimum amounts - just enough coat threads and no more. When you pull them apart years later, you can't really tell other than they're whistle clean.
It would actually make more sense to spec faster tighness the same way you do as you do on heads these days and you wouldn't have this problem. But until then, torque is the best (only?) way.
I have been changing tires for 20+ years and have had more trouble with dry studs than with greased ones, just like bolts anywhere else on a car. I don't think that changing tires is rocket science. I have always tightened lugs by hand, no torque wrench. You get a feel for it over time. I have never had bent rotors, or anything else bent by tightening lugs too tight, and I have never had a lug nut come off from not tightening them enough. Friction changes with the conditions. Lubed would be less, dry would be more. If you need to use strain gauges to figure out if you are tightening your lug nuts properly, I believe that you are overthinking the issue. If you are in the engineering department of a auto manufacturer, then you need to to the engineering studies, but if you don't know how to tighten a lug nut without pulling out a calculator, then buy Billy-Bob a beer and let him do it. I use my micrometers to measure critical dimensions, not to change my tires.
NOPE i do not use it, Toyota manual says Torque to 83 ft Lb says nothing about adding anti-sleeze! does mention use no oil or lubricant on studs under a yellow caution stating wheels going to fall of if ya use it! if the nuts do not go on i would use a wire brush or a thread chaser maybe and clean up the threads! I think everyone has a couple that are hard to hand tighten but NO ANTI-SLEEZE needed just use the socket and ratchet or tire iron! addition of anti-sleeze or wd40 aka spray gasoline not needed! Just about all the dealerships i have been to have no clue to what a torque value is for tire rotations or a torque stick, they just zap them on with HIGH PSI air ratchets and some of them go way above 350Ft Lb. That can't be good for any wheel stud since some of the higher torqued ones are like only 150 ft Lb. So i would strongly suggest running a torque wrench across all lug nuts unless ya did them yourself! manufacturer gives a spec for a reason and that reason is not to ignore torque specs! Section 8 Owners Manual http://www.tirerack.com/wheels/tech/...jsp?techid=107
re: Anti-seize on lug nut studs, why or why not?
if the nuts do not go on i would use a wire brush or a thread chaser maybe and clean up the threads! I think everyone has a couple that are hard to hand tighten but NO ANTI-SLEEZE needed
just use the socket and ratchet or tire iron! addition of anti-sleeze or wd40 aka spray gasoline not needed!
Just about all the dealerships i have been to have no clue to what a torque value is for tire rotations or a torque stick, they just zap them on with HIGH PSI air ratchets and some of them go way above 350Ft Lb. That can't be good for any wheel stud since some of the higher torqued ones are like only 150 ft Lb. So i would strongly suggest running a torque wrench across all lug nuts unless ya did them yourself! manufacturer gives a spec for a reason and that reason is not to ignore torque specs!
Section 8 Owners Manual
Linear Mode
