Subaru field engineer says OEM wheel studs only good for 75 to 80 wheel changes
 

I was talking with a BRZ friend of mine recently that is a knowledgeable, experienced driver. He pays close attention to vehicle maintenance including wheel lug torque specs. He recently had a couple OEM wheels come loose on the track. Fortunately he was able to get the car slowed down in time to keep them from coming off. His wheels were damaged, so he spoke with his dealership about it. After giving him a hard time, he was finally able to speak with the field engineer about this issue. The engineer said the OEM studs and lug nuts are only designed to withstand 75 to 80 changes over the life of the vehicle. My friend actually had the failed studs tested and said the metallurgy is terrible. Here is an email I got from him about it:

re : the Subie engineer and my wheel studs and lug nuts, he was a pretty cagey dude. he would put nothing in writing for me despite several requests. Clearly, the design life of parts is not something they want to discuss openly. I felt pretty lucky that they replaced both ruined wheels as a "courtesy" rather than under warranty. He made it very clear however that our cars "arent designed for track use ". and "this car isnt a Porsche". of course I said they "why isnt all that in the owners manual ?" .
bottom line is the "design life" of the lug nuts and studs is 75-80 wheel changes, on average, in the lifetime of the car. "Kmart" parts used in quite a few places on a $25K car, I suspect.
In order for you to avoid my issues, I strongly recommend you go to ARP studs, kit # 100-7727 for FRS or BRZ. their tensile strength exceeds grade 10.9 steel so they are the best you can get.
For your information, I researched the stock studs and lug nuts. they are made from < grade 8.8 carbon steel. in short that means they are el-cheapo Kmart parts.
grade 10.9 alloy steel is generally the best steel other than "aircraft quality" . ARP has a tensile strength rating system and their's are better than grade 10.9.

Be careful out there, kids!

It happened also to me after removing different bolts. They were so soft that the head was deformed. I had to replace them with new ones. In fact the service manual suggests many times to replace the bolds. Does this mean that this car is cheap? No! Think about if all these bolts, studs and other parts of the car were made from high strength steel. Think about how much more the car would weight. Do you know the weight of a basic Porsche Cayman? :)

Mine didn't even last that long before cross threading.

Roughly 150lbs more than a BRZ Limited.

With build quality that is an order of Magnitude higher, much higher quality materials etc.

Go look up the video of Bill Caswell doing 50 straight, launch control starts in a 911 Turbo and the car never overheating, going into limp mode, etc. Try this in a GTR and watch the transmission puke on the ground after the 4-5th time straight you do it. You simply can't compare the build quality of Porsche to basically anything else.


They constantly rank number #1 in initial quality, quality of replacement parts, etc.


Sorry, it was 61 straight launches.

[ame="https://www.youtube.com/watch?v=A5DRCTW-Q7o"]THe 2014 Porsche 911 Turbo | Road and Track - YouTube[/ame]

High quality doesn't equate to high weight.
Aircraft aluminum
Carbon fiber
Forged wheels
etc.

Failed part lab testing? Access to a Subaru engineer? I must hang in the wrong circles.

Even Dorman's cheap aftermarket replacement stud specifically for our cars shows grade 10.9 on the head.

I'd be interested in hearing the science on what they found in the OE stud. I've heard of Subarus having these problems for years, but not so much on Nissans using 12x1.25 studs. I figured a finite number of subcontractors churned out the OE stuff.

I asked for more detail but that is all I was able to get, unfortunately.

@Pat did you do the metalurgical analysis done?
@JimR: R35 GTRs shear studs all the time.

Dorman's set of studs goes for $40. ARP's is maybe $200. Is there really much difference? As JimR noted, "Even Dorman's cheap aftermarket replacement stud specifically for our cars shows grade 10.9 on the head."
Generally you get what you pay for, but if the grades are the same, how much difference can there be?

What kind of tires was your friend using?

From my tracking experiences it is relatively common to break studs on many car platforms with sticky tires on track. 350z, 135i, mustang gt. They are basically a wear item.

Lol nice. I'll have to let Bill know that somebody used his video on this forum. :D

And ironically do you know who builds Boeing's wings? Subaru!

You guys, don't know what you buy. Do you know about their special ring-shaped structure? Firefighters are doing special training on the Subaru's because they could not cut their b-pillars. You can read more details here: http://www.firehouse.com/article/105...orcement-frame

If something really matters, then be sure that Subaru will do the best and use the best materials.

The E30 guys have followed Bill since his crazy rally race in Mexico. :D

lol... this guy in the video is funny! I haven't seen more ridiculous car review :bellyroll:


And where did you found that Cayman weights 150 lbs more? Cayman is in the range of 3,000 lbs which is roughly +400 lbs. And don't forget, Cayman is a 2-seater. 911 Turbo S is a nice car, but it is far away from the category of BRZ. We should be reasonable when doing comparisons ...

Why is your BRZ so light?

Unfortunately not. I have provided as much detail as I have.

Perspective, >95% of 86's will never see track duty I'd wager. Seriously consider how often wheels come off say your mom's sedan, maybe once every 2-3 years for a brake job or tire replacement? Hell I bet I've driven cars that haven't had their wheels taken off in nearly 5 years.

75-80 wheel installations is not a ludicrous lifespan for a economy car, I'm just glad most people strip the threads before they shear the bolts. ARP studs went on my car about 9 months ago after I stripped the OE studs. Makes me feel better that it wasn't operator error, only wish I had kept track of wheel on/offs, I don't think I surpassed 50...

:burnrubber:

Full tank of gas and all equipment the 86 comes out to 2750 pretty consistently, strip the trunk and run it under a quarter tank and you'll be under 2,700 lbs. One of the few upsides to this car not many people talk about, it really is a lightweight while most cars come out heavier than advertised. I want to say that some manufacturers advertise dry weight, so no oil in the engine, coolant in the radiator, or fuel in the tank so the actual cars come in 100+ lbs heavier than the spec sheet.

http://www.ft86club.com/forums/showthread.php?p=845661
http://www.ft86club.com/forums/showthread.php?p=362020
http://www.vorshlag.com/forums/showthread.php?t=8275

I was just confused as to how 3000-2750=400+ lbs, But reading it again i see its +400 not 400+

The ARP studs are lengthened - if you need to run spacers, you have the room.

The ARP studs also have a little bit of dead area with no threads at the end of the stud. This little detail makes it almost impossible to cross thread the stud when putting it back on.

Above all realize that if you race your car, studs/lugs are a wear item and should be replaced regularly - even if you've upgraded.

If responsibly done, tire rotations count in there as well, which can be up to 2-3 times per year. Add in one extra for winter rubber (at least in the northern zones) and you have 4 tire changes per year. That means that we will wear out the studs after 18 years--Wait, nevermind, thats totally reasonable. :lol:

And he's adding 100lbs to the Cayman.......which also has 50% more HP.

And he completely ignored everything I said regarding build quality. Porsche is at the top of the heap when it comes to any mass-produced vehicle. And bests many of the boutique vehicles.

EDIT: Guess depends on if we are talking about the Cayman or the 718 Cayman. The new Turbo 718s are a touch heavier ~3000 lbs. The 6 cyl cars are ~2900 lbs.

But still 2764 (published base weight) to ~3000 is 236 lbs, not 400.

Exactly, this discussion was pretty much useless. Personally I replied because there was a suspicion in the topic that Subaru is a cheap company. For sure it does not have the glamor of Porsche or other big companies, but it is an earnest car manufacturer. In some cases much more earnest than the bigger guys.

If I got 80 changes, I'd be a super happy man. Instead, I'm waiting until I can install these ARP studs.

The 1st generation Cayman (987c) which was produced till 2013 was heavier. The base car with the 265PS weighted 3,100 lbs. The newer versions are lighter, but also newer designs.

For me quality is a relevant thing. If you mean the leather and the premium feel, then you are right. If you mean not to break, then I insist that Subarus are better.

Do you know who was the chief designer of Porsche all these years? Do you know who designed 911, Cayman, Cayenne? His name was Pinky Lai. He was a designer from China. Try google and you will find a lot about this guy. Do you still believe that Porsche is a real German company?


I will not say anything else because we are already off topic :)

Our STX car endured 2 full seasons of autocross, changing tires 2-3 times each weekend.

Stock studs, no issues.

-alex

I don't even know what to say.

Don't forget your meds in the morning.

ARP offers an OEM length option now.

IIRC RS3s.

Good for you.

My daily driver lasted one autocross and two wheel changes/removals before stripping two studs in the first couple months of ownership.

That was after 9 years of owning an Impreza with the same bolt pattern on stock studs with dozens of wheel changes/removals and NEVER a stripped stud...

I'm just gonna keep using my torque stick when I zip them on after hand threading to start, and checking afterwards with the torque wrench.

Then again I only have my wheels off 5 or 6 times a year.

If I strip or break a single one I'm upgrading the full set.

I previously owned and autocrossed a 2010 WRX and currently do the same with a 2014 BRZ. I cross-threaded a couple of studs on the WRX after two years of autox using the stock hardware; however, once I retired the lug nuts and started using some copper grease a couple of times a year I had no more issues.

I haven't had any issues yet with the BRZ by avoiding the stock lug nuts (my autox buddies mostly switched to extended studs as a prophylactic measure). Studs aren't hard to do on our cars and are often necessary for wheel and spacer combinations anyway, needing to take extra care with the studs or lug nuts is a little disappointing but is a common Subaru "quirk".

Does it help at all if anti seize is used?

Just remember a lubricated lug/nut needs a lower tq spec than a "dry" one.

I've only ever used anti-seize when using Al lugs on ARP studs.

Depends on why the studs are failing.

I'm of the opinion that most of the studs are failing (the stripped ones anyway) because of debris getting into the threads and people just muscle through the resistance deforming and weakening the threads. If you're using anti-seize to prevent the lug and stud from grinding and creating little metal shavings you might get some extra life out of them. If you let the anti-seize become a dirt magnet and don't keep the studs clean you'll accelerate the wear.

As mentioned above, anti-seize means that if you torque a lubricated bolt vs. an un-lubricated bolt to the same value you will put more force and stress on the lubricated bolt. Less friction in the threads = more force being applied to tighten it down.

There is endless debate on this, and I've never been arsed enough to care, the basic and intuitive answer is that yes, you should torque to a lower value. But practically speaking, torquing lugs in your driveway you'll almost never hit precisely 89 ft-lbs. Auto manufacturers know this, and this is one of those areas where the proper precautions have almost assuredly been made.

Give it a google:
https://www.google.com/webhp?sourcei...0bolt%20torque
This one looked good to me, the linked chart roughly gives us that ~90 ft-lbs dry = ~70 ft-lbs lubed, I wouldn't trust it though.
http://www.busconversions.com/bbs/in...?topic=15160.0

Yup, Subaru decided to save themselves a couple bucks per stud and they won't last forever for the guys who swap wheels two or three times per month. $1/stud * 5 * 4 * 200,000 = $4 million, I certainly don't blame them.

Have there been many cases of studs snapping on track? If there are I missed them. Like with every other affordable car, the 86 is built 'well enough'. Most of the studs fail on track because they see extreme heat cycles that the average commuter car will never see.

tl;dr keep it simple, keep the studs clean and dry
I lubed up my ARP+Al lugs like above, it was ok, didn't make me feel any better about it, I'm going to let it dry out and flake away and just do my best to keep the studs clean this time. I torqued to 89 ft-lbs because I'm acting on faith that all the important margins of safety have been calculated and it doesn't matter if I torque it to 70 or 110 ft-lbs.

I consider upgraded studs and nuts to be like upgraded brake fluid, pads, and lines - just something necessary to do to the car before ever putting a wheel on the track.

The CSG BRZ has never stripped or damaged a stock stud. No exact count, but I can confidently say it has had 400+ wheel changes done.

Anti-sieze is ALWAYS used, and refreshed regularly, and torqued to 80 lb/ft by hand, every change. Lugs are almost always impacted off, and impacted on, before hand torquing.

A lot of this is because of careful technique and strict adherence to be best practices.

I had two studs / lugs get screwed up the second time my wheels were removed to go on the dyno. And I was present both times - and the lugs were hand threaded back on, always. So this is no surprise to me. Car only had 5000 miles on it at the time.

This is what I've always heard as well. Is there a recommendation as to how frequently to replace studs/lugs?

No anti seize, torqued to 90, changed wheels many times, tracked heavily, no issues ...

This thread feels like a typical internet overblown horror story. Yeah, sh@t happens sometimes, but 99% of the time all is good. I'd worry about something else personally... Like the upcoming prez elections!

Per Alleged Subaru tech: after 90is wheel changes

Per CSG: after 400+ changes