Sheared lug studs are caused by bad studs or bad lug nuts?
 

Would replacing the lug nuts with some premium brand like McGuard help to avoid the lug nut binding issue? I've only had one, and now use anti-seize, but don't want another one. Prefer not to replace the OEM studs, especially if they are not the cause.

Caused by user error or contaminated studs.

I have never stripped or broken a wheel stud when doing it right, i.e. hand thread on first turn or two then gun/wrench if needed. I always use cloth to clean threads, and if open ended lugs I take extra care to clean them up when wheels come off.

Studs get some dirt/grime on them and any extra resistance causes it to cross thread and break.

My experience is 20 years of DIY work on all my cars, plus about 200 track days on/off over that period. Lots of wheel changes, sometimes 3-5 times a day, never broke a stud.

Key is to not rush the work. Don't swap wheels like you're a NASCAR mechanic. Aftermarket studs like ARP only give you a false sense of security, you can still break those studs... just a lot harder and a lot messier when you do.

I don't think BRZ is known for stripping threads (user error) The studs are known to be weak, I thought. I've had a nut seize onto a stud, and I head to shear it off with a breaker. No way it was user error. I hand tighten all lugs, and then use a torque wrench. Never an impact.

I have had zero issues with the studs. Hand tighten, and torque with hand tools.

I've had aluminum lug nuts cause corrosion and ended up stripping.

I've never experienced this; using an impact to install the nut. Wheel nut into a socket and spinning it on. Easy way to cross thread the stud.

Are the OEM BRZ lug nuts made of aluminum?
If they are, then I want to replace them.

Are the OEM lug nuts inferior?
Like the 2-piece kind that get stripped on the outer cap?

I prefer the OEM look, what should I buy?
I want zero tuner flash, just quality that is more reliable and not likely to get stuck.
What brand ? Gorilla? McGard?

There's definitely something about Subaru's tin foil lugs.. i've taken my cars (Hondas, Benzes, Volvos, Toyotas) to the same tire shop for years..i've watched them use torque wrenches. and have never had a problem before my FR-S. Every time i've changed tires there's been a problem. Not sure though since this is my only Subaru.

I have some McGard lugs and am gonna change to ARP studs soon.

User error.

I had my wheels on and off more times than I care to remember.

Some points from an old guy:
1. Use a torque wrench (if you don't own a couple of torque wrenches your not doing it right)
2. Always wind the nut in by hand, never start with the impact driver, ugga dugga will kill em quick if the thread hasn't been started correctly.
3. I personally use the tiniest dab of anti-seize (50% of the internet will explode from this statement)
4. Always use closed nuts, open ended nuts will let contamination into the threads.
5. Cheap aluminium nuts are rubbish, use steel, or, if you need bling, Ti or Chromium-molybdenium steel like project Mu with floating seats.

Or, break them because monkey fisted, and then blame the product.

Or, just say they are rubbish in order to justify the purchase of some "brand name" studs in order to gain more "Bro" points to impress all the teenage boys.......

Different issue I've had:


>Lug nut tin caps from OEM lugnuts popped off on three of mine while torquing them during wheel rotation.< I previously had no idea the these lug nuts are a cheapo two piece design.

(Had I known in advance that this would be an issue, I'd have used a much deeper socket than the one I've used for years on many other vehicles).


I'd like to replace these lug nuts with something which looks stock, yet is a better quality product.

I'll say I agree with the "user error" thing, but since most cars are fine with the abuse of cross threading and impact torquing, it does cast the Twins' wheel studs in a bad light.

I disagree with the "user error" thing.
Because this is the only car I have ever had where I broke a stud by hand. And I have had a lot of cars. I always screw the nuts on and off by hand so as not to cross thread them. A couple years ago a stud just snapped off when I removed it. I think it was one of the very few times I brought the car to the tire place to have them replaced. So they were probably over torqued. I usually remove the wheels and bring them with the new tires to be replaced. It was easy enough to replace the stud but WTF?
I just had my tires changed the other day and I noticed when I was putting the wheels back on the car, the nuts were really "crunchy" going on the studs. I should have anti-seized them but it was hot as hell out and sweat was in my eyes.
They'll probably snap next time I remove them.

Short answer: Just going with a premium reputable brand (I'm looking at Muteki, McGard, Gorilla, and others right now) *might* be sufficient to avoid the nut/stud galling/stripping problem. Maybe... It's pretty inexpensive and of course super-easy installation, so I say give it a shot!

After my experience I think better studs by themselves are not sufficient, if you get aftermarket premium studs, also get known good lug nuts. This may seem obvious to some but for whatever reason it wasn't for me!

I got ARP studs before I did my first track day with the BRZ in Spring of 2017 and have just used the factory lug nuts. Getting ready for track event last month, when swapping brake pads out I had trouble removing one lug nut on the right rear :o Late afternoon before the event of course! Couldn't source an M12x1.25 tap for external threads, but borrowed a "clean-up" nut from local shop and bought new lug nuts (forget the brand but definitely not premium name-brand) from local PepBoys. No real problem with swapping race tires on/off a couple of times at the track, I think I caught it before significant damage to the stud.

Now with an event coming up in a week, I think it's time to order some "real" lug nuts though!

I always use a torque wrench, but the car does sometimes have wheels removed/replaced by trusted local shop.

But this has happened enough with these cars that "user error" doesn't cut it. Stock lug nuts and/or studs are marginal at best. I had thought known-good aftermarket studs would prevent issues, but clearly not in my case. It *could* be that premium lug nuts by themselves are sufficient.

I've never had an issue on any car. I always thread by hand until they are tight. Then I weld them on with my air impact. I change my wheels multiple times a year on multiple vehicles.

I think years of owning BMWs with lug studs helped reinforce my patience

All OEM studs are weak. They're cast iron...

Here's a list of studs I've broken by hand, via breaker bar:

OE Nissan
OE Toyota
OE Subaru
Nismo
ARP

The question of how it breaks/shears is a question of what caused you to put so much torque on it that it breaks. Keep in mind that you're supposed to tighten the lugs to around 80-90 ft-lb of torque, so if it stops moving and you're still applying torque, it will break. 80-90 isn't a lot of force if you're doing it right, especially if you are using a longer breaker bar or torque wrench.

Nobody has time to look up torque specs until after the failure.