My guess is that those crappy studs were over torqued when installed causing cracks. The loosing just caused them to break off at the cracks. The closeup photo of the stud shows some discoloration towards the right of center making me think it has been cracked prior to just snapping off while trying to loosen. I'd never use spacers on anything like a SD. (or anything else for that matter).

 

looks like torsional shear to me https://www.onallcylinders.com/2014/...ener-failures/

 

It's interesting that none of the broken studs in the Bora spacers appear to have stretched.

Instead, they appear to be full diameter all the way up to the breaking point, where they twisted apart.

Over torquing an OEM wheel stud will cause it to stretch before tensile failure.



This stretching, or necking down, did not happen with the Bora studs.

 

if you are happy with the spacers, this seems to be the most reasonable and cost effective way to go.

 

There have been many references to "over torquing" these studs. My question is, what constitutes over torquing? At what point would one reasonably expect a stud to twist into two pieces? I am certain that the employees at this particular Discount Tire did not make a concerted effort to break the studs. They go through the same process dozens of times a day, six days a week. I watched the kid doing the final torque on the wheel that eventually had six broken studs. He weighed maybe 130 pounds. It took a little effort on his part, but while I was watching, he got a partial turn on the nuts before the torque wrench clicked. I find it impossible to believe that they did anything extraordinary enough to result in a total of eight broken studs.

It looks like this might be a open and shut case of inferior material. I expected better. Each one of these spacers cost more than a full set on eBay. I still find it hard to believe based on all of the glowing reviews on the internet. It took a lot of convincing for me to install spacers, and after a couple years of research, it was clear that this was the way to go. Well, maybe not so clear.

 

After reading all the "glowing reviews" on the internet, how could it not be true?

 

What do you gain from having these wheel spacers?

 

I know, right? The bubble has been burst.

But seriously, these are not commercial reviews that I'm talking about. I read a lot of forum posts. Forums are full of people complaining about products (look no further than this post) and I literally saw none of that in regards to BORA.

 

Looks. That's it. In many cases, spacers are used to clear aftermarket suspension parts or bigger brakes. At least a practical case can be made in that scenario. Mine is pure vanity.

I also run "high quality" hub centric spacers (and longer lug bolts) on my BMW 4 Series. Those are 15 mm in the rear and 12 mm in the front. I have no concerns about spacers in that application. Guys run drift cars with spacers and generally have no issues. That is not an 8000 pound truck hitched to a 12,000 pound trailer.

 

I just realized that the replacement studs they sent me are completely different. Based on the stamp, these are rated, correct?

 

Unless you can verify the manufacturer, you have to assume the new studs are made of Chinesium. I would see if ARP has that stud in their catalog.

 

Yes that's one of the common grades used, the other is 8.8. 10.9 will snap easier rather than deform before failure. This could lead to a "what's the best oil" type argument.
No more metallurgy from me today there's a tropical storm keeping me on youtube...

 

I'll take safety over vanity everyday. A wheel coming off a 4 ton truck towing a 4 ton trailer at 65 mph is not a pretty sight.

 

Stock torque is 165 ft-lbs. If he used that spec, aftermarket stuff would probably twist like noodles.

 

Yes, those are very good. Those will serve you well