How does the collective we feel about 6061 lug nuts? I ordered ARP studs for the Miata and clicked to buy new lug nuts along with the studs. They showed up (a month late) yesterday and to my surprise they are aluminum. Since they just came in an unmarked package, I called the company who sold them to me to see what they are and they told me they're made of 6061.
So. Run them? Run them but keep a close eye on them? Run away from them?
I run them, but keep a very close eye. I worry about the threads, as theyre not a steel threaded insert. Just aluminum.
If they can't be returned, I'd run them until if/when they start causing issues then replace with steel.
Porsche has used them since the 60's. Jensen used 'em on those heavy old 440 powered Interceptor tanks. Looks like Honda uses them too.
Lube them, torque them to spec and revel in the mind bending performance increase of reducing 0.005% of unsprung rotating mass. 
Trent said:Porsche has used them since the 60's. Jensen used 'em on those heavy old 440 powered Interceptor tanks. Looks like Honda uses them too.
Lube them, torque them to spec and revel in the mind bending performance increase of reducing 0.005% of unsprung rotating mass.
I can't find any evidence of honda using aluminum lug nuts. Considering most of the japanese manufacturers like to use steel inserts in their wheels for the lug seating surface, I can't imagine they'd use aluminum lug nuts.
Porsche did use aluminum (I think some of them might have actually been magnesium?) lug nuts for a long time. But the first thing that pretty much anyone does with them is toss them on a shelf and replace them with steel nuts. With the 996/986 generation they switched to lug bolts which are obviously steel.
Does it matter if you have steel or alloy rims ?
Porsche used aluminum lug nuts with the Fuchs alloys , but used steel lug nuts with the standard steel rims ,
Just wondering if the expansion is the same for steel vs alloy when they heat up ?
I had some 949 racing aluminum lug nuts on my first Miata (way to focus on the important things, right?)
Don't use an impact gun on them, and make sure the studs are long enough for full engagement.
Copper anti-seize and go. I used them on my NA track rat with ARP studs.
Many guys run the 949 Alumnium lugs without issue.
Typically aluminum lug nuts would be made from 7075 alloy.
Personally I would not trust 6061 in this application.
https://www.kloecknermetals.com/blog/7075-aluminum-vs-6061-aluminum/
How Strong Are They?
When looking at both alloys in the “T6 condition” (meaning that the material is heat-treated with a solution, then it is aged), it’s noticeable that 7075 T6 aluminum properties feature a tensile strength that is nearly double that of 6061 T6 aluminum properties. The shear strength of 7075-T6 is estimated to be 1.5 times that of 6061-T6. 7075 T6 aluminum is substantially harder as well.
z31maniac said:Copper anti-seize and go. I used them on my NA track rat with ARP studs.
Many guys run the 949 Alumnium lugs without issue.
https://949racing.com/product/949-racing-7075-forged-alloy-lugs-12x1-5-thread/
These are in fact 7075
Aluminum can be made strong enough, but it doesn't like to take a thread and has a finite fatigue life. I might race with them after testing and checking and disposing of after a race or two, but I would never run them on the street.
I've run aluminum lugnuts on my Miata for the past 3 or 4 years, both autocrossing and street usage. I've never had an issue.
I've been using my FM version of them for two seasons now. Other than the anodization coming/scratching off, they appear to be in good working order still.
My Miata came with a set of 949 Racing aluminum lug nuts when I bought it in 2019. The car was trailered, used exclusively for autocross with multiple events, including Nationals.
I replaced them with a set of Al nuts from Flyin Miata. It's still only used for autocross, but I do drive it to the events.
I don't use any antiseize, the wheels are swapped every event. One of the first questions I posted on this forum was asking about lubricating wheel studs. I think I remember that the consensus was that doing so would change the torque values since the torque requirements were for a non lubricated nut and stud.
I'd like to hear opinions on that again.
I'll rattle them off with my impact. When installing them, I'll set the impact at the lowest setting, which just barely gets them snug, then torque to 85 ft/lbs after lowering the car.
I had never heard of aluminum lug nuts, before the Bentley thread with its dull golden colored lug nuts!
I've personally never seen or heard of a lug nut problem that was actually caused by anti-seize, and not a different problem, blamed on lube (yes, it changes torque spec, but that's easy)
So, I may not be the best source. That being said, I would NEVER consider using dissimilar metals without anti seize.
I wouldn't have imagined aluminum nuts was a good plan, but trust the info presented, so with the right alloy, guess so!
Personally I would not use them. I'm sure it can be done safely if you pay enough attention to getting the right ones, treating them properly expiring them after an appropriate lifetime, etc. I just don't see the point -- the miniscule weight savings are not worth the hassle.
In reply to Floating Doc (Forum Supporter) :
In my experience with actual torque tests (sub construction and such, not lugs) a dry torque is less consistent than a lubed one.
Yes, the lubed torque value would be slightly lower, but no where near enough different to matter on steel lug/studs/wheels. If anyone blames breaking a stud on lube, they just don't know (or won't admit) what they did wrong.
If aluminum lugs will take the 85 ft/lbs., at all, and obviously will, torquing them lubed, ain't a problem. Torque 'em to 84 if it makes someone feel better 
I thought the Porsche lug nuts were titanium?
They're aluminum as far as I can tell.
For the record, I wouldn't be concerned about outright strength. For me it's the risk of galling the threads and the annoyance of the extra care needed, with basically zero upside to them. But if I already had them on hand, I'd probably use them until they started causing trouble. If it's a car that sees 1-2 tire swaps per year, they might be just fine. For a car that gets tires swapped every weekend I just wouldn't want to deal with the extra annoyance or risk of damage. But they're not unsafe or anything.
In reply to MiniDave :
No the connecting rods in the 70s were for the S motor I think. My 79 924S had aluminum lug nuts which I may still have somewhere. Switched them to steel, I think it might have been a requirement for Drivers Ed events.
In reply to 03Panther :
According to
https://www.antiseize.com/PDFs/torque_specifications.pdf
torque should be reduced by 25% when using anti-seize.
A little more feedback on using 6061 aluminum in this application:
At work we make a lot of parts from 6061-T6. One of our high volume components is made from this, and has 3/8-16 tapped holes. It's anodized, assembled with 3/8-16 SHCS’s, and torqued to ~40 ft lbs.
3/16-16 threads are pretty close to M10-1.5, so a bit smaller than the most common M12-1.5 lug studs, but with the lower torque it should be fairly comparable.
Anyway, after re-using one of these assemblies a few times, the threads in the aluminum inevitably begin to gall and/or strip… YMMV...
I really appreciate all the feedback everyone. This is a race car so the wheels are going on and off all the time. The plus side of that is I would always have them under close watch. The negative is that they'll constantly be getting torqued and removed meaning more chances for the threads to get screwy.
It was such a pain to even get these from the company that I don't really want to bother trying to return them. Maybe to get my money's worth I'll plan to run them for a weekend under close watch and then pitch them.
To me a better way to reduce lug nut weight is to simply get a smaller steel nut. 17mm socket versions are available that won't weigh much more than the physically much bigger aluminum ones.
In reply to therieldeal :
Yep, totally understand. To be clear, I did not and would not have ordered these intentionally. I just assumed since there was no specific detail given that they were just normal open lug nuts.
In reply to RX8driver:
Agreed although these are the size of a 17mm steel nut.
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