Sheared Clean Off

[Dub_James]

Possible vandalism or theft?

[Highspeed]

Had the studs been previously overtorqued by tire shop?

That's very common. For every single mechanic who does the job right, there are ten more half trained chimps who just zip the things up as tight as their impact gun will go.

[Yogimus]

Meanwhile, 200 miles back, there is a minivan of dead nuns upside down in a ditch after avoiding an on-coming wheel.

[Highspeed]

Meanwhile, 200 miles back, there is a minivan of dead nuns upside down in a ditch after avoiding an on-coming wheel.

On their way to distribute toys to an orphanage for dying kids

I once let a friend of mine shoot my Remy 700 PSS, and he put a round into the air due to a booger hook and bang switch malfunction ( he was ex-military and therefore unsafe around guns ) - fuck knows where it landed.
The UK is population dense, I did shit myself for a while wondering if it had brained some fucking kid a mile away or something.

[308Mike]

The UK is population dense, I did shit myself for a while wondering if it had brained some fucking kid a mile away or something.

Who knows, it might have knocked some sense into him to value FREEDOM over state power!!

[Netpackrat]

Had the studs been previously overtorqued by tire shop?

That's very common. For every single mechanic who does the job right, there are ten more half trained chimps who just zip the things up as tight as their impact gun will go.

Especially if the vehicle in question is "just a trailer." Though in my experience, that attitude is most prevalent among trailer owners. When I had a customer who wanted something done as cheaply as possible, or the unsalvageable salvaged, as often as not it was for his (but never her) trailer. Turned plenty of those guys away... A few of them would come back and buy new tires/wheels from me, after examining their options elsewhere, but I didn't really give a shit.

Some of the cheapest bastards were always the commercial fishermen... They'd have many tens of thousands tied up in their fishing vessel, which they relied upon to make their living. And then they would put it on a crappy old trailer made from steel tubing that was on the verge of rusting out, sitting on re-purposed mobile home axles, no brakes, paper-thin saltwater rusted rims, and cracking tires. Saw more than one of those guys pulled over between the harbor and their house, boat loaded and leaning towards the side with one or more flat tires, mangled rims, etc. Desperately trying to jack all of that weight up, so they could bring me the remnants of their tire(s), because not one of those guys owned a spare for their POS trailer.

[evan price]

Trailers have a lot of side loading on the wheels. Especially tandem axles like that. I've seen studs snap off but it was usually from being hella overloaded and then doing a lot of twisting and turning.
I would first suspect someone overtorqued those lugs to beyond the stress point then they eventually failed. If you were heavy loaded, one or two failing would overload the remaining ones and they will snap right off.
I have seen on trailers that have not had the wheels off often they will get moisture trapped in the cavity formed around the lug stud between the lug nut and the hub face, inside the wheel hole. This will rust the stud in that one spot and cause failure.
Another thought (and I've seen this in other parts) is counterfeit hardware supplied by the vendor to the hub/axle supplier. The studs were cheap counterfeit parts and they were not heat treated. Believe it or not, faking hardware is a huge industry.
If it were my trailer, I would inspect ALL the rest of the wheels and invest in a new set of 24 lug studs and nuts. Sure it will cost a little bit but do you want to take a chance on this happening again? The other wheel on that side of the trailer has now had to support all of the load for that side by itself and anything that was questionable is now surely strained. Should be under $100 in hardware, you can do it yourself. Need a heavy hammer to pound out the old studs (if pressed in which most are). You grease the threads of the new stud and then use one of the old lug nuts turned backwards along with a big wrench or preferably an impact gun to draw the stud into the hub casting.

[Netpackrat]

If it were my trailer, I would inspect ALL the rest of the wheels and invest in a new set of 24 lug studs and nuts.

I endorse this message. Bonus points for cleaning, inspecting, and re-packing the wheel bearings while you are at it.

[Rich Jordan]

Do trailer wheels index on the hub center itself or only on the studs? I know that using Ford steel wheels on a Chrysler is possible but because the wheel center hole is larger you lose the support you would have with a tighter fitting Chrysler wheel. The only sheer-off like that I ever saw was a big block Mopar running Mustang styled steel wheels; afterwards they figured that the wheel hadn't been torqued down in sequence, one lug tightened all the way 'trapped' it slightly off center, then the others also tightened down without seating properly. The wheel was then free to move across the hub face because of the lack of center index (and of course was loose on the lugs once it 'popped' out of the trapped position), and eventually sheared off the lugs.

[Wrenchbender1]

Yikes! I'm going to do the same here in a few weeks. Hopefully without the drama. What hitch are you using? I was thinking about an Equal-i-zer hitch.