Hey everyone,

So I'm looking for lug nuts, and I'm seeing a bunch of Aluminum ones, some Titanium, but no Stainless steel...I'm just curious as to why? Or maybe it's just me and people do make it but I didnt see any.

Any help is appreciated!

 

Weight, typically. Aluminum and Titanium are much lighter materials. Stainless steel is pretty heavy, and given the fact that its in constant contact with steel lug studs, it can still rust. This makes it no better than a standard steel lug nut that has been chromed.

 

^Thanks for your input. The weight factor is negligible, but the second point you brought up may be true...

 

Actually, the weight factor is pretty significant, seeing as it is unsprung weight. Saving even a pound at each corner is significant, when it is unsprung.

 

We're talking 4-5 grams per corner...not a pound

 

Factory lug nuts are about 45grams each. I've seen aluminum ones as light as 22grams, and a titanium set was 20grams. So there is some weight savings there.

 

if you don't have the cool titanium or aluminum ones...you won't be considered cool on this site.

of course you'd never, ever, ever see/feel/benefit from the negligible weight difference.....but it's just not cool to have lugs made of stainless

 

bump

 

stainless would probably seize up with the heat overtime.

 

Gorilla Automotive made them

http://www.amazon.com/Gorilla-Automo.../dp/B000CMJ3JU

 

Most lug nuts are made of plated steel. Perhaps some are made of titanium, but few are made of aluminum; it's not nearly as strong as steel.

The Gorilla lug nuts are not fully stainless; they are two-part units. A full stainless steel unit would be more expensive as stainless steel is worth many times what alloy steel costs by weight, not to mention the added cost in tooling and production since stainless steel is more difficult to cut.

As far as weight goes, though, stainless steel weighs about the same as alloy steel (and again, almost all lug nuts are alloy steel).

 

Yes, steel lug nuts dominate the OEM market but Aluminum lugs dominate the current aftermarket lug nut trend. Inch for inch aluminum is the same strength as steel or stronger. This has been proven more than a few times so please post your source(s) of information or test(s) that prove steel is outright stronger than aluminum. Fatigue is the weak point for Aluminum but the main reason why aluminum lugs were not mass produced until recently is because of the cost of manufacturing. Ti is even more expensive to manufacture and has a tendency to gall dissimilar metals which can lead to premature failure. This makes aluminum the clear winner even though it has a finite life. People will take the loss of unsprung weight with extra cost over the weight and lower costs of steel lugs. They just will not be able to use the lugs for 50 years.

Here's a little more of my silly input. Wheels (let it be steel, aluminum, magnesium, unobtanium or whatever) should get lugs of a similar metal. In a perfect world without cost constraints and ridiculous markups, Everybody would be running ultra light wheels made of some type of hyper alloy with, Ti alloy lugs and nuts

 

Weight, strength, and cost are definitely not the death of steel lug nuts.
I guess they're considerable variables, but the big reason has already been mentioned ...

BINGO!

We do not suggest stainless steel lugs because of the potential to rust. If any of the finish deteriorates, the stud and lug become susceptible to moisture. Any moisture which makes contact will eventually rust and seize. So you get the tiniest chip on the inside of your lug nut, and install your wheels ... Then 6 months later ... They're stuck on!
Removing a seized lug nut isn't impossible, but it's an unnecessary hassle.

I can think of 10 good reasons NOT to use steel lugs, but why would anyone want them? OP?

 

Anti-seize is your friend with any lugnut. I have anti-seize on damn near every thread on my car and it makes removing and re-installing all parts much easier including wheel nuts....

 

The only way you could be correct in saying that aluminum is stronger than steel is if you qualified that statement by restricting the two materials to having the same mass in any given system. Matweb.com is pretty handy; if you do a search there you'll note that the strongest conventional aluminum alloy, which happens to be 7075 with T6 heat treat, has an MOE of 72 GPa (a measure of "stiffness" in the tensile orientation while behaving elastically, or "safely") and a yield tensile strength of up to 475 MPa (a measure of how much stretching a material can take without permanent deformation). 4340 steel, which is a rather commonplace alloy steel, has an MOE about 3 times higher, at 205 GPa, and a YTS of approx 1000 MPa, which is more than twice as high. So, like I said, unless you're comparing with equal weight, steel will always be stronger than aluminum.

I agree that titanium is expensive both in material cost and in fabrication, and is excellent for high-stress, low-mass applications. Last I heard, though, it galled strongly only to itself.

You have to be careful with torquing the nuts if you really anti-seize the whole nut. Generally, the bolt stretch (and therefore, clamping force) doesn't change too much per given tightening torque if only the threads are lubricated. However, if you lubricate the nut bearing surface as well, bolt stretch can skyrocket even with the same tightening torque. YMMV as there are no readily available studies that show actual changes in bolt stretch vs torque with different lubrication states.

FWIW, I torque at 80 ft-lbs while my manual calls for 100 ft-lbs, after having lubed all the threads while keeping the nut bearing surfaces dry. Torquing at 100 ft-bs now causes my rotors to warp and make brushing noises.

Pitting corrosion is definitely a phenomenon common to metals that use an oxide layer for protection, e.g. aluminum, stainless steel, etc, and so what you describe could definitely happen. Pitting corrosion happens when the oxide layer is compromised in a specific area, allowing rapid galvanic corrosion to happen "through" the hole.

However, if you think about it, the same thing happens in a significant fraction of wheel installs. Nearly all aluminum wheels are installed with chrome- or zinc-plated steel lug nuts or lug bolts, and yet, even though the aluminum oxide protective layer gets ground off every time the lug nuts are installed, there is no significant corrosion after removal. Perhaps it's because after tightening, the metals actually form a hermetic seal, keeping corrosion-causing oxygen out?