Extended wheel lug failure after less than two years

[Pklauser]

Just had a Bimmerworld 37mm extended lug bolt fail on me after originally being installed at the beginning of 2022. Went to torque my lugs after a project, and only a few pounds into it, one totally let go.

Car is tracked several times a month, had ~15 events in this time span, but I never torque hot lugs. I do use my impact when putting the wheels on, but just to zip down until the impact hits one time, then I torque to spec once on the ground.

Looking to figure out if this is related to something I'm doing, I had a bad lug, or what. Is using my impact to even that one click excessive? Anything else I'm missing? I understand folks replace lug bolts or studs every two years, which was my plan, but I'm guessing I should up that to every one year. For some reason I thought lug bolts would be more reliable than studs, but this seems on par with the stud game, removing "reliability" from the "pros" column of bolts for me.

[maupineda]

How thick of a spacer are you running? And what wheel specs?

[Pklauser]

17x9.5 ET35 Apex ARC8 wheels with an Apex 12mm hubcentric spacer

[eacmen]

Have you done the wheel spacer test (video below)? I would also contact bimmerworld to see what they say.

Be thankful you didn't have a moment on track!

https://youtu.be/lK0bzjInqWU

[Pklauser]

I have on one set of wheels, but I'll double check with these.

Bimmerworld's own product page goes as far as suggesting replacing the bolts with every brake change, though it also says to replace them "every few years". The brake job interval must be assuming street use. https://www.bimmerworld.com/Wheels-T...Bolts-M12.html

I'll reach out and report back.

[Slideways]

Either it is a bad bolt or the spacer is not sitting flush. The inner rear hub can contact those 12mm spacers at the hub centric portion and cause the spacer to not sit flush.

[Nate047]

Check the mounting surface on the wheels too, make sure they are still true to shape.

[Pklauser]

Paper test is passing on the spacer to wheel interface on all wheels as well as the spacer to hub (well brake disc). I'm leaning towards bad bolt but don't have any real way to confirm that suspicion.

Yee haw I'm real glad I found this before getting out to the track, or worse, on track like eacmen suggested.

Still have yet to extract the remnants. It broke below the brake disc, so I'm going to pull that off and see if there's something I can grab onto before I resort to drilling. If I was smart I would've grabbed a left handed bit when I was just at HF.

[eacmen]

Please do report this to Bimmerworld. If there is a known bad batch of bolts I'm sure they would want to know.

[Estoril]

What does a close-up of the failed lug face look like?

I don't use an impact on my track car studs/bolts. Impact wrenches torque to an unknown spec. What does your maintenance shop use? Tire shop? The only way I'd use a torque wrench is with a torque stick rated at 80 ft lbs. Then torque up to target value.

[eacmen]

What does a close-up of the failed lug face look like?

I don't use an impact on my track car studs/bolts. Impact wrenches torque to an unknown spec. What does your maintenance shop use? Tire shop? The only way I'd use a torque wrench is with a torque stick rated at 80 ft lbs. Then torque up to target value.

I use an impact wrench to remove the lug nuts and studs. To tighten I use an impact wrench on the lowest torque setting then follow up with a torque wrench. With a battery operates torque wrench this is safe. This same method with an air impact may result in over torque as the air impact spins so much faster than the battery driven ones.

Using the method above I still end up needing to do a couple full rotations of the torque wrench.

[Estoril]

I use an impact wrench to remove the lug nuts and studs. To tighten I use an impact wrench on the lowest torque setting then follow up with a torque wrench. With a battery operates torque wrench this is safe. This same method with an air impact may result in over torque as the air impact spins so much faster than the battery driven ones.

Using the method above I still end up needing to do a couple full rotations of the torque wrench.

I personally wouldn't use an impact to remove them either - but thats just me. An M4 driven by a friend paddocked next to me had his right-rear studs fail approaching apex. The wall impact repair cost him a lot of money.



I like my wheel hardware simple and rock-solid. Its one less thing to think about. Again - thats just me.

[Estoril]

BTW - I would replace all bolts on all wheels.

[eacmen]

I personally wouldn't use an impact to remove them either - but thats just me. An M4 driven by a friend paddocked next to me had his right-rear studs fail approaching apex. The wall impact repair cost him a lot of money.



I like my wheel hardware simple and rock-solid. Its one less thing to think about. Again - thats just me.

From my understanding most studs fail due to repeated over torque, hot pit changes, bad wheel spacers, or running with undertorque'd nuts.

As I see it the only risk of using an impact to remove lug nuts is loosening the stud itself. The same risk exists using a breaker bar. As long as you are inspecting the studs each wheel change to make sure they aren't loose I feel the risk of using of an impact is mitigated.

Not trying to dismiss your concern just giving my $0.02. Everyone needs to perform their own risk calculus.

[eacmen]

BTW - I would replace all bolts on all wheels.

Concur. 100 percent. All those bolts need to be changed.