FlyYellow

i would check the drop links and see if they are in tact. i've heard of something like this happening with a snapped drop link.

Garth S

Does this car have LSD? If so, a broken or separated half shaft would cause a torque shift to the remaining driven wheel. Otherwise, with an open diff, the car would have lost all forward drive - and at modest speeds, that would not cause a spin.

Marv

Wheel-off light comes on!

Bull

A friend had what sounds like the same thing happen at Summit Point last year....in the paddock after having just completed a run in the Instructor group! The lower control arm snapped with a sound that could be heard across the Paddock. It was fun getting the car on the trailer.....

slapshot

Wow . . . this is really kind of scary. Multiple entries on similar accidents happening due to similar part failures. With all we do with our cars, it would seem there are situations - track/canyons/LAfreeway that such a failure would be absolutely catastrophic. Zero margin for error. Glad your friend was ok.

What did you find Edward?

Flying Finn

Yeah, sure.

I actually was in Weissach test center when Porsche tested the new 997's electornic nannies.

It was truly amazing to see the test where they blew off the whole rear suspension and electronics kicked in, created animated 3D suspension set-up (it came out from the sat nav screen which in itself was amazing) and saved Walter Rohl's ***, just like that!

Jeff,

Glad to hear your friend is ok. That really is scary when something like rear axle, suspension or similar breaks and you obviously have very slim chance to predict it happening and doing something to save it.

Maybe time to take a close look at all the stuff under the car.

TomF

Stock suspension or aftermarket? I have been wondering about the propensity for the lower control arm to break with stock sways and PSS-9s or Bilstein HDs. As I have discovered, there is very little room for error when lowering the 993 with this setup. The stock sways are really not designed for this kind of lowering. Under certain conditions, it appears possible for the rear bar to contact the control arm.

Get us pics, please! It really could be useful for the group.

simpateko

hi tom
suspension and ride height are completly stock.
i saw it last in a storage yard and the back end was sitting too close to the ground to see anything.
not sure if i will get a chance to see it up on a lift.
the insurance company has moved it now.
thanks for all of your comments!
jeff

Edward

Well FWIW, I poked my head underneath my 993. If the wheel was found facing skyward, complete with hub still mounted, I can only guess that it was one of the two lower control arms. But as I said before, these are beefy pieces. Moreover, Jeff had mentioned that his buddy was not flying around the corner, and so I'm guessing the stress was mild at best, especially considering what we do to these cars at the track.

I wonder if there was some previous damage, say, impact damage at that corner, where parts were replaced but a stress fracture in one of the lower control arms went unnoticed. Afterall, if an arm is not bent and the car aligns properly, it could easily go unnoticed until it finally gives way. What's the history of the car, Jeff? Any thoughts on possible previous collision? What the car needs is an actual expert to assess the carnage, not just an insurance adjuster, so who knows if we'll ever really know the cause.

To Tom's concerns, any swaybar/control arm contact would be readily heard/felt. And if there is sufficient clearance throughout the full range of motion at rest, there shouldn't be any contact in a mildly-stressed car under street conditions ...unless something else goes. And even then, a swaybar contacting the lower arm is a nuissance, not a catastrophe. ...unless I'm missing something here, of course

Edward

Bull

Stress from use and any off road excursions/impacts can build up over time. I have seen a lower control arm snap when a car was lowered on a jack after having a wheel changed. You know something big snapped if you ever hear the sound it makes.

simpateko

edward
thanks for taking a look.
my friend bought the car used about 3 years ago.
supposed to have been an accident free, 2 owner car when he got it.
he has put about 10,000 miles on it.
he had a lwfw put in about 2 years ago by a top quality shop.
they checked the car over for him and said it was very nice.

do you think a blowout of the right rear tire could have caused the spin and the left control arm broke when the rear hit the wall?
thanks again to all of you!
jeff

slider

haven't mastered how to cut/paste a link, but do a search on Dave Parker for 4/17/06 and there is a good thread and photo of a ball joint failure that sounds alot like you've described happened to your buddy

aam993

Here is the link to Dave Parker's thread mentioned above: https://rennlist.com/forums/993-forum/267369-97-lower-rear-ball-joint-failure.html

autobonrun

Could the position of the wheel be a result of the impact rather than the actual cause? Just another thought.

digdoug2001

I am glad your friend is OK...sounds like his was much worse than mine. I crashed my 96 993 C2 this morning. The other driver went north on a southbound street...ran me off the road and then the guy took off...gutless...