Interesting Failure

[89SHOMAN666]

Any of you other forced induction guys had this happen?

I guess this is what happens when you run 24 PSI. :laugh_ti: This was the outcome of my Sunday.

 

[jon93]

Carnage!

 

[Off Road SHO]

CV damage! Big Time. 24 PSI eh? And that's all you did? I'm impressed.

Tom

 

[SuperchargedSHOguy]

24 psi in the tires?!? LOL
I don't miss having to worry about CV's or transmissions anymore.

 

[89SHOMAN666]

Yeah I don't know what went first the bearing or the Half-Shaft. All I know is the only thing that held on the wheel was the Wilwood's. I'll take a picture of the caliper damage tomorrow. As soon as I removed the caliper the rotor and hub fell on my lap.

 

[SuperchargedSHOguy]

Thats a scary situation. New hubs are fairly cheap though and I am sure you have some spare axles lying around.

 

[Sho Amo]

is that thing powdercoated? thats a good looking hub.

 

[89SHOMAN666]

Yes its P/C'ed, thanks! Yup she's almost up and running again but I decided to do the other side for safe measure. Somethings telling me this is my sign to not only do HD H-Shafts but a Gen-3 SF-Swap.

 

[gmorrell]

I'm troubled by that failure, and I tend to think it would have happened if you'd been running 24 psi or 0.24psi. If the failure was simply too much torque through the half shaft, I'd expect that the splined shaft would have broken at the base of the splines, IOW, the half shaft would have separated at the back of the hub, not the front, leaving the splined stub inside the hub.

Your failure is not at the base of the splines, but rather at the base of the threaded stub on the shaft. I'd be suspicious of hub flex that may have put bending forces on the end of the threaded stub. Are there any witness marks from the rotor contacting the caliper in the fire path?

Where and how did this failure occur? Road course? Sticky track tires?

 

[89SHOMAN666]

It was a road course failure and the car wasn't even being abused to terribly. There were significant rotor marks from it impacting the caliper but that was post failure. The rotor was clean 2 miles prior to the failure, so I am trying to figure out if the wheel bearing failed causing the shaft failure or whether it was the other way around. I'll post some pictures later this afternoon of the caliper and rotor damage. Either way thank goodness the caliper retained the wheel!

 

[gmorrell]

How about the other (unbroken) side? Any evidence of hub flex over there?

I agree that it could have been induced by failure of the outer bearing, and unfortunately, the ensuing carnage probably covered up any evidence of the initial failure.

Don't rule out hub flex as a problem on these cars. You take a heavy street car, bolt on fat, sticky tires, double (or more...) the engine horsepower, throw in some extra heat from a big brake package, and stuff starts moving around way more than anyone ever intended it to.

The other thing that seems to be at play is that aftermarket hub metallurgy isn't what Ford put into the OEM parts. Some of the aftermarket hubs just seem to be (Chinese?) junk.

Somebody needs to look into making a good billet or forged hub for these cars: Something with thicker sections, larger fillets and radius', lug bore sizes for proper ARP wheel studs, and maybe even a different (5 X 4.5") lug pattern. It would be a bit spendy, but it might just solve the bearing life issues these cars are having when they're used hard, like on a road course.

 

[rubydist]

It would be worth pulling other side apart, and having the end of the half-shaft magna-fluxed to see if there is any fatigue crack on that side.

I agree with the assessment that the break is not due to torque overload, but something else - like the hub flexing or the bearing going bad or some combination thereof.

Since wheels falling off are very bad in the best of situations, and potentially fatal in the situation where one is cornering at or near the limit, its worth doing the homework to figure out the cause....

 

[SHO NUT]

Yup she's almost up and running again but I decided to do the other side for safe measure. Somethings telling me this is my sign to not only do HD H-Shafts but a Gen-3 SF-Swap.

I just finished the Gen III subframe conversion on my blower car. If nothing else, it makes the required maintenance wheel bearing replacements just a bolt-in job, and not require a press, which is a real PITA when you have a bearing failure at a track.




from:

http://www.shoforum.com/showthread.php?p=1065404

 

[AREA 91]

Any of you other forced induction guys had this happen?

I guess this is what happens when you run 24 PSI. :laugh_ti: This was the outcome of my Sunday.

I have done that N/A. It's fun when parts literally "fly" off the car.

 

[89SHOMAN666]

Well hear is a picture of the caliper damage, sorry for it being blurry, I hate auto focus cameras.


Just to clarify both sides are getting all new hardware (spindles, bearings, H-shafts), as I do not feel like having a repeat anytime soon. However after this summer the car is going into my shop for a g3 SF-Swap.

As soon as Tony's GB finishes I'll also have HD-Gears, and with them I plan on having Josh get me some HD-H-Shafts. Hopefully that will be a semi-permanent solution to the problem.

I really appreciate everyone expertise regarding the issue.

 

[drivinhard]

The other thing that seems to be at play is that aftermarket hub metallurgy isn't what Ford put into the OEM parts. Some of the aftermarket hubs just seem to be (Chinese?) junk.

Seen a lot of aftermarket (read, chinese junk) C5 wheel bearing failures at the track recently to. Between these, and rotors, and knock off repro wheels (which I'd never use), when they come to take us over after we can't make good on our debts, they will have already killed all of us at track days/time trials/racing.

 

[89SHOMAN666]

Well I was able to get it together and make it to my local car show this weekend! Looking forward removing some of these weak links in the drive line so hopefully these types of failures don't occur in the future.





Got the award for most interesting car!

 

[1995SHO9]

Pink floyd, fuc yah!

 

[Sho Amo]

is that kurt metros' old car.

 

[89SHOMAN666]

is that kurt metros' old car.

Yes minus the engine and trans they've been upgraded. :woo-hoo: