It's easier than you think: how to convert to lug studs

 why not swap to lug studs?

Reasons.  

If one is careful with the lug nuts, not overtorquing and not using lug nuts that are threaded all the way to the base, they are perfectly fine, but bolts are a lot more hamfist-tolerant.

Shanked lug nuts eliminate the thread damage issues but they introduce their own problems.

Installing wheels onto my E30 sucked so much less when I changed to studs.

Nice video. I'm putting some spacers on and really prefer studs over bolts. No worry for having the right length bolts and easy to swap different wheel configurations.

I converted the M3 to studs. So much easier. 

So last August at the Glen a number of cars broke studs that needed to be extracted and replaced. This was a BMW CCA event so lots of wheel bolts in the pits. I asked our group who had ever broke a wheel bolt and nobody had but breaking studs seemed almost commonplace. I'm sure part of that is more cars on the racier end of things are running studs and being pushed harder but there were still lots of heavy M3/4's rolling around on stock hardware with sticky tires not having any problems.

So other than it is slightly easier to mount a tire (which matters for a race car where super quick tires changes are important) why would I actually want to spend the money to convert to studs for my track/autocross only car? Seems like an expensive way to make an important system less reliable

In reply to adam525i :

I'm curious how many of them went to studs because they were using spacers? That could be a contributing factor for breakage.

I plan to change my son's audi tt to studs. It has different width spacers front and rear with the appropriate length bolts. Some day either he, or someone else besides me is going to change the wheels and put the bolts in the wrong place.  Then, the wheels are going to fall off one end, and the bolts are going to go right into the abs ring on the other

https://www.core4motorsports.com/gallery-of-broken-bmw-wheel-studs
 

My E46 is getting switched back to bolts this season. 

I've converted all my BMWs and Benzes to lug studs. The only thing I would add is I run an ARP thread cleaning chaser bit through each hole before installing the new studs. With 30+ year-old cars, there's always some corrosion/dirt/junk in there. I feel better starting with clean threads.

As for broken lug studs...here are some thoughts.

• There's a huge quality differential. MSI studs have proven to be bulletproof. Good enough for NASCAR, IMSA, Pirelli World Challenge, etc. etc. anyway.
• People tend to over-torque them when installing, which stretches them out and weakens them. You need to torque them to something like 18-20 lbs/ft. Barely more than hand-tight. The fact that broken studs always break right in the hub suggests this is the primary issue.
• People tend to do stupid E36 M3 like slathering wheel/hub mating surfaces in anti-seize, which makes it harder to keep the wheel clamped in place.

adam525i said:

So other than it is slightly easier to mount a tire (which matters for a race car where super quick tires changes are important) why would I actually want to spend the money to convert to studs for my track/autocross only car? Seems like an expensive way to make an important system less reliable

It's a lot more than "slightly easier", IME.

200 track hours on my E46 M3 race car with studs and so far so good.  They do get replaced on the same interval as the wheel bearings, though.  Buy the good ones, install them properly, and then don't drive around with either overtorqued or (even worse) loose lug nuts.

I suspect that they break at the hub because that is where the stress is.

I am not pointing fingers, but I also do wonder about wheel torquing habits.  Any wheel that has tapered or ball seat lug nuts is lugcentric, to some small degree.  If you zip the first lug nut down tight, the wheel is clamped THERE, even though the other four lugs are off center relative to the wheel.  Tightening the other lug nuts isn't going to center the wheel, there is now too much friction because of that first one.

Then you drive it, and braking and cornering forces are enough to shift the wheel.  Now you have four loose lugs and one tight one.  The wheel will continue to shift around, and will eventually break the tight lug's stud from bending it back and forth.

It has been a hot minute since I paid attention to BMW lug bolts, but teh Volvo has two piece bolts, probably for this exact reason.

I started retorquing lug nuts after a short drive, on anything I have had the wheels off of.  What I find is that if one lug nut has loosened up, all but one will have loosened up...

It's good to hear some different experiences with them and opinions. I'm betting user/installation error is a factor in the things breaking, just because someone has a cool track toy it doesn't mean they're fully qualified to work on it.

My car runs 16 x 8 wheels and they pretty much hang off the hub centres so they are pretty easy to swap around, if I'm in a tight space I grab the tool out of the trunklid toolkit that lines everything up. I am running spacers on the front with longer bolts, I've picked up a new set and retired the old set to backup duty, maybe next time I'll buy studs so I can fit in with the cool kids :) 

repoman said:

https://www.core4motorsports.com/gallery-of-broken-bmw-wheel-studs
 

My E46 is getting switched back to bolts this season. 

Yeah, I'll stick with bolts lol.

I converted to studs by selling the last of my German cars. 

BMW's studs are 16mm which make them even more prone to failure versus an 18mm stud (eg Porsche). There is likely to never be a failure if you run lug bolts, and likely never to be a failure if you swap studs every 2 years. Your call if the convenience is worth the $$$.

Honestly, I prefer bolts. I never had much of a problem with wheel changes either, especially with most new cars being hubcentric.