Single wheel hop on fg

pugslyyy

Expedition Vehicle Engineer Guy
Ride on bitumen is smooth enough I eventually noticed the slight wobble and slight to/fro under load from three sheared wheel studs (out of five). Yup, I know, I now have wheel nut indicators. I just have to remember to look! lol:

I can't imagine driving with 3 sheared studs. I was sweating riding with 1 sheared - and I have the wheel nut indicators so I could see the lugs next to the sheared one slowly cranking around.

Guess I'm just a weenie.

Fuso SRW right rear sheared stud.jpg
 

mog

Kodiak Buckaroo
I was sweating riding with 1 sheared - and I have the wheel nut indicators so I could see the lugs next to the sheared one slowly cranking around.

Is there more to the story? Do you think the sheared stud was caused by a loose nut(s), or the loose nuts caused by the sheared stud (chicken or egg?).
 

pugslyyy

Expedition Vehicle Engineer Guy
Is there more to the story? Do you think the sheared stud was caused by a loose nut(s), or the loose nuts caused by the sheared stud (chicken or egg?).

The previous owner replaced the tires when he bought the truck (they were dry-rotted) and the installer used what must have been a "strong as the hands of God" impact wrench to attach them. This wheel was the absolute worst one to get off, and one lug in particular (the one that sheared after 5000+ miles on the trip). The sheared lug stretched/turned a few days before it sheared so I could tell something was happening with it. Since I know all the lugs got overtorqued when I lost one I was then concerned that there was going to be more failures on that corner.
 

Flys Lo

Adventurer
In response to the OP's question, wheel "hop" to me is axle wrapping, it sounds like that isn't what is happening to you.

That said, if this issue occurs at any speed, I would almost guarantee its not the tyres being out of balance.
It is possible that they are out of round. Is it definitely coming from the rear axle? If so, I would be checking your wheel bearings.
If you can't be sure if its coming from the front or the rear axle (it can be surprisingly hard to tell at times!), check the play in all your front end components.
 

gait

Explorer
in my case one loose nut, which caused the first broken stud. And so on.

The fracture face of the stud was partially ductile before the catastrophic brittle failure - classic fatigue prior to failure. The bevel seat in the wheel was "worked". The second and third had less working on the seat and less ductile (more brittle) fracture suggesting more movement (greater stress on other studs) once the first stud had failed.

The second and third stud failures were either side of the first.

An almost all brittle fracture face without working of the seat would have suggested a simple failure of the stud.

(Sorry to be technical, I was originally trained as a metallurgist and many years ago spent some time in laboratory investigating failures in steel (customer complaints!).)
 
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