Mystery stud

[Mike Burch]

A bit of a mystery, this.

I found this broken stud lying on the road yesterday. My first thought was that some poor sod is going to discover (hopefully not the hard way) that one wheel of his vehicle is not as well attached as it should be. But then I realised that the broken bit of stud in my hand was very oily. And oil is not at all common on wheel studs. So—what's is it from?

The thread is metric fine, M12 x 1.25. The split tapered thingy suggests that the stud held something which required accurate centring, like a wheel. The broken end has the remains of an unidentifiable thread.

If you look carefully at the filthiest end of the thread in the picture of the bare stud, there is some wear evident on the peaks of the thread. This wear is on only one side of the stud, suggesting some sort of uneven stress.

How would that wear occur? And if this is not a wheel stud, what is it?

[NiftyNev]

That split tapered collar suggests it is from a front wheel hub cover of probably a 4WD of whatever make. The split tapered collar centres the hub cover so the splines of the drive shaft are centered.

Here's a link to what I am trying to explain -

https://www.onlineautoparts.com.au/p...CABEgKuuPD_BwE

[danlb]

It looks like the type of thing that you usually have to remove from the bottom of an engine. Maybe for bolting in the transmission.

I found a similar piece alongside the road, but it turned out to be a tungsten tooth from a Ditch-Witch. You know, the kind that has a 12 foot tall toothed wheel to dig trenches.

Dan

[NiftyNev]

The split item is usually called a Cone Washer. The stud size on my Toyota Surf are only M8 x 1.25.

[gambler]

12mm is pretty big for a 4x4 hub, that is what they look like on early toyotas, but way too big. probably off a piece of earth moving equipment, bobcat or small tractor.

[welderskelter]

Looks like someone has stolen the R model Mack truck I drive. It usually sheds a couple of them off the left rear drive axle in beet season each year. And thats how I spot them is the axle leaks oil and is very noticeable. Sure thats not a 3/4in.

[Rustybolt]

First of all. How bored do you have to be to be picking up random bits of metal in the road?
I'm retired and I'm not that bored, yet.
Secondly. I'll go out on a limb here. What was it used for? I'm gonna say some piece of power equipment that was being hauled on or used next to said road.
Finally. It is kinda interresting in that," I wonder what that was used for." kinda way.
Put it back in the road. Someone might be looking for it.

[Willy]

Looks like a stud that is used on larger full floating drive axles to fasten the axle to the hub.
They usually use the tapered seat cones to locate the drive axle to the hub. 12mm would indicate a larger truck drive axle.

[Tim Clarke]

Willy has got it. I've changed enough of these over 40 years of monkeywrenching to know all about them....

[Mike Burch]

Looks like someone has stolen the R model Mack truck I drive. It usually sheds a couple of them off the left rear drive axle in beet season each year. And thats how I spot them is the axle leaks oil and is very noticeable. Sure thats not a 3/4in.

Yes, I am sure. 11.9mm is nowhere near 3/4".

Willy and Tim—thanks. That could well be the case.

[Noitoen]

The stud goes into one of those axles made out of old ship anchor chains

[Doozer]

Looks like a stud that is used on larger full floating drive axles to fasten the axle to the hub.
They usually use the tapered seat cones to locate the drive axle to the hub. 12mm would indicate a larger truck drive axle.

Full floating axles have splines on both ends.
Semi-floating have splines on one end and a flange on the other.

-Doozer

[Willy]

Full floating axles have splines on both ends.
Semi-floating have splines on one end and a flange on the other.

-Doozer

It has nothing to do with splines on either end. A semi-floating axle is one in which the axle has a bearing pressed onto the flange or hub end. It not only transmits torque from the differential it is also required to carry the weight of the vehicle.

A full floating axle only transmits torque to the wheel hub, a hub which houses the bearings which in turn ride on a spindle that is part of axle housing assembly. The fact that it only transmits torque and is not required to carry vehicle weight is why it is called a full floating axle. Versus the semi-floating axle that only floats on the inboard splines and is under the stress of the vehicle's weight on the outboard end.

Edited to add illustration: