The hubs fail.

--Ian

 

The hub.

 

Crikey......

Glad you are still in one piece and perceivably the damage was not too extensive.

 

Glad you are all right Supersuckers!
That is just disturbing to watch!
Jeez!

 

Holy crap! Stock OEM? Original or have ​​​​you replaced at some point?

 

That's scary as hell. Can't believe you did not flip. I for sure would have needed new pants. How bad is the rest of the car?

 

Likely OEM.Car has 60k and ~120 hours track time.

 

Car is in surprisingly good shape. A little sheet metal damage in the wheel well, frame rail is a little deformed, busted CV boots, a slightly scuffed control arm, and the wheel and tire are toast.

I suspect one thing that helped me is that I had replaced the factory brace behind the diff with a 1x2" piece of steel for greater exhaust clearance. The custom brace is an inch lower than the factory brace and took the brunt of the impact and kept the car a little further up off the ground. Also a great jack point. (Diff pic is post repair)

 

Had you ever inspected it? I look at mine for cracks before every track day... not sure if that would catch it though.

 

I'd inspect them when I changed the pads. Moving forward I'll replace every season. The juice ain't worth the squeezing if you try and run them longer.

 

Reading back through. Do we have a part number for the ARP extended studs needed for use with the Doorman larger stud hubs.

And should wheel studs be replaced with hubs? I assume so, but figured I'd ask what the norm was.

 

According to Bundy, it appears to be 100-7717. looking through the specs of the stud they look right for the reported changes in the Dorman hub. I'll be purchasing both shortly and follow up.

Yes. worst case is you spent an extra couple bucks for no reason.

 

Ok, so I just bought a few of the Dorman 930-550 rear hubs from Rock Auto for around $15/ea.
They are made in China.


They are drilled with a ~0.552" hole for the wheel stud.
The closest 'murican drill sizes are:
35/64=0.5469
9/16=0.5625
The closest metric drill size:14mm=0.5512


I then measured the knurled diameter of the original stud to be 0.571"


These are the ARP wheel studs which are specified for the 94-05 rear.


ARP says they have a 0.579" knurl diameter, so that means I can measure good.


I really don't know what size stud they should be.
The ARP 100-7717 has a knurled diameter of 0.565", which is 0.006" smaller than the original studs. The 100-7720 is 0.008" oversize.
I had no issues installing the 100-7720 with my hazard fraught ball joint press. Either will fit in the end. I didn't see anything in the machinist's handbook about press fit with knurling, so I'm not sure if it functions the same as a standard interference fit joint or not. I don't know how to measure the inner diameter of the knurled stud, unless I cut a stud in half so I can get the calipers on it.
Anyone want to start cutting studs in half to measure for the good of the internets?

I looked on the ARP site and the only sizes are 0.565 or 0.579/0.580, so take your pick.

 

Meh. I just run whatever studs come with the hubs.

 

When I called ARP to ask about mis-sized holes on front hubs, they recommended that the major diameter of the knurl should be .005 bigger than the ID of a round hole. Not sure how that applies to a measurement taken off a hole that's been deformed from previous stud installation.

 

Once you add spacers and aluminum hats (which are a few mm thicker than stock steel rotors), there aren't many threads left on a stock stud.

--Ian

 

I'm not certain, but I would expect that properly-sized studs are sized to keep the hub in the elastic deformation zone (ie, will return to original shape when you pull it out). Once you get into plastic deformation, the strength drops.

--Ian

 

The (front) hubs I've seen have all had visible ridges from the knurls of the original studs after they were removed.

I'm not saying the hub is changing shape and stretching out, just an indentation, so the necking phenomenon past yield in a tensile strength test wouldn't apply.

 

I am interested to know how many rear hubs rock auto has sold in the last two weeks because of this video. I know I got a set.

 

Do you guys always replace the bearings at the same time?
That was scary indeed...