Shock tower failure on 718 Spyder
#106
Rennlist Member
I don't have photos to post, but a guy on the Facebook Spyder group experienced complete shock tower failure on his 12 day old Spyder - in street driving! I don't know much more than that, but this issue had of course previously occurred with 981 GT4s; I had not previously heard of this issue occurring with the 718 chassis.
#107
As the towers on the 718 seem to be the same as 981 I was only inquiring if anyone has heard of the failure on the current models since this thread started.
#108
His theory is just that, stiffer suspension can weaken towers over time, this is why there have been no cases of failures in the other 718 variants (S, GTS) since they came out (to his knowledge).
Assuming they are also tracked and abused you'd imagine there would be just as many documented in the different variants.
#109
RL Community Team
Rennlist Member
Rennlist Member
Huh? Suspension stiffness and travel length are independent. You could have really soft (bouncy, floaty) suspension but still have very long travel or really firm suspension and very short (or long) travel. And are you sure you can claim that tower failure on the 981 was due to bottoming out? It could have been, but it certainly could occur without any bottoming. Really stiff suspension can transmit a lot of force without ever bottoming.
Also remember that any significant impact can be at fault including deep potholes or running up over a curb to mention only a couple, simply driving along a regular road as reported by some does not contribute to this type of failure.
#110
Rennlist Member
This is what the tech at my dealer said. He has not seen any failures on 718s or 981s for that matter but has heard of them.
His theory is just that, stiffer suspension can weaken towers over time, this is why there have been no cases of failures in the other 718 variants (S, GTS) since they came out (to his knowledge).
Assuming they are also tracked and abused you'd imagine there would be just as many documented in the different variants.
His theory is just that, stiffer suspension can weaken towers over time, this is why there have been no cases of failures in the other 718 variants (S, GTS) since they came out (to his knowledge).
Assuming they are also tracked and abused you'd imagine there would be just as many documented in the different variants.
#111
Every report front strut tower failure that I could find followed a significant impact or off road incident. Determining this was time consuming due to the lack of disclosure by many of the individuals involved.
Also remember that any significant impact can be at fault including deep potholes or running up over a curb to mention only a couple, simply driving along a regular road as reported by some does not contribute to this type of failure.
Also remember that any significant impact can be at fault including deep potholes or running up over a curb to mention only a couple, simply driving along a regular road as reported by some does not contribute to this type of failure.
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2XIPA (12-21-2020)
#112
Rennlist Member
Every report front strut tower failure that I could find followed a significant impact or off road incident. Determining this was time consuming due to the lack of disclosure by many of the individuals involved.
Also remember that any significant impact can be at fault including deep potholes or running up over a curb to mention only a couple, simply driving along a regular road as reported by some does not contribute to this type of failure.
Also remember that any significant impact can be at fault including deep potholes or running up over a curb to mention only a couple, simply driving along a regular road as reported by some does not contribute to this type of failure.
#113
Drifting
My education on aluminum is old and my brain is pretty much useless thanks to this year so take this as opinion instead of fact:
I'm not too worried about the strut tower failure problem happening on the 718s. The 981 strut tower problem looks like an cast aluminum problem (I'm not 100% sure the towers are cast aluminum, but the sheers on the 981 GT4s look like they are cast, and I'm not sure how they'd give that portion of the car the strength it needs in aluminum without using castings), with it being too brittle, probably from manufacturing it improperly (heat treating it or something else) when the bends are formed. I would definitely call that a design flaw, but it's not uncommon for strut towers to take massive forces from impacts. I inspected an Acura MDX that hit a chunk of cement on the highway; it inverted the strut tower on the impact side of the vehicle and put a diagonal buckle in the roof from the body flexing so much. Aluminum is far more brittle than steel so what may only bend steel, may split aluminum. It's pretty common for cast aluminum suspension components to completely sheer in half under any sort of decent impact. Sheered strut tower tops are rare probably only because so few vehicles are built with inner structures of aluminum.
Change ups are pretty common on vehicles and some manufacturers can have multiple of the same part within a year (seen dodge do that). So it would be very weird if Porsche did not look into this problem and quietly do a change up on the part with a different process of manufacturing, increased thickness, or different heat treating or whatever so that the 718s do not suffer from the same problem as the 981. It also could be a bad run where there never was a design flaw and it was just a month or 2 their production of the aprons were out of tolerances for heat treating or whatever that caused them to be more brittle and less tolerant of impacts.
The only thing I do not like is if this is purely from impacts, something else should have been engineered to bend or sheer before this happened. Generally on a suspension hit you should see components closest to the wheel fail or get compromised first. Example: You don't have a bent sub frame unless you have a bent control arm.
I'm not too worried about the strut tower failure problem happening on the 718s. The 981 strut tower problem looks like an cast aluminum problem (I'm not 100% sure the towers are cast aluminum, but the sheers on the 981 GT4s look like they are cast, and I'm not sure how they'd give that portion of the car the strength it needs in aluminum without using castings), with it being too brittle, probably from manufacturing it improperly (heat treating it or something else) when the bends are formed. I would definitely call that a design flaw, but it's not uncommon for strut towers to take massive forces from impacts. I inspected an Acura MDX that hit a chunk of cement on the highway; it inverted the strut tower on the impact side of the vehicle and put a diagonal buckle in the roof from the body flexing so much. Aluminum is far more brittle than steel so what may only bend steel, may split aluminum. It's pretty common for cast aluminum suspension components to completely sheer in half under any sort of decent impact. Sheered strut tower tops are rare probably only because so few vehicles are built with inner structures of aluminum.
Change ups are pretty common on vehicles and some manufacturers can have multiple of the same part within a year (seen dodge do that). So it would be very weird if Porsche did not look into this problem and quietly do a change up on the part with a different process of manufacturing, increased thickness, or different heat treating or whatever so that the 718s do not suffer from the same problem as the 981. It also could be a bad run where there never was a design flaw and it was just a month or 2 their production of the aprons were out of tolerances for heat treating or whatever that caused them to be more brittle and less tolerant of impacts.
The only thing I do not like is if this is purely from impacts, something else should have been engineered to bend or sheer before this happened. Generally on a suspension hit you should see components closest to the wheel fail or get compromised first. Example: You don't have a bent sub frame unless you have a bent control arm.
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wizee (12-22-2020)
#114
#116
Need strut tower mount right front 718 base
Hi all. Good reason. I bought this car wrecked and need some structure parts. One is the passenger side mount. No dealer as of yet will sell to me as they want cert shop. Has anyone produced after market? Anyone help me get one ? Thanks
#117
Instructor
Porsche supplies them to certified repairers only. Certified repairers have the expertise and tools (esp. the celette) to effect a safe restoration. Do you?
#118
Drifting
Going to be brutally honest here. You're in over your head.
If you were in the industry you'd know Porsche only releases that to a certified shop and you'd know there is zero chance of aftermarket strut towers. No one makes aftermarket strut towers for a toyota corolla let alone a Porsche.
Whoever is fixing the car for you is also in over their head as they should have answered those questions to you instantly.
It will also be next to impossible for you to find a certified shop that will sell you those parts. Knowing the types of owners and people that run a shop of that caliber having worked at a high end shop before, I think most of them quite literally would rather cancel their insurance and then burn their shop down rather than sell you structural parts. Sell the car back through copart or wherever you got it from, or have a certified shop change the strut tower which frankly is not a crazy expensive repair compared to doing some other body repairs on Porsches.
If you were in the industry you'd know Porsche only releases that to a certified shop and you'd know there is zero chance of aftermarket strut towers. No one makes aftermarket strut towers for a toyota corolla let alone a Porsche.
Whoever is fixing the car for you is also in over their head as they should have answered those questions to you instantly.
It will also be next to impossible for you to find a certified shop that will sell you those parts. Knowing the types of owners and people that run a shop of that caliber having worked at a high end shop before, I think most of them quite literally would rather cancel their insurance and then burn their shop down rather than sell you structural parts. Sell the car back through copart or wherever you got it from, or have a certified shop change the strut tower which frankly is not a crazy expensive repair compared to doing some other body repairs on Porsches.
#119
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I’ve read that thread before. Not everyone admitted hitting something, because they don’t want to pay for it. But they all hit something at some point. There is no way the strut towers just failed driving down the road. People lie about damage to their cars all the time.
Recall @Joe Weinstein never "hit something" but he had lowered his car and was a serious autocross competitor. His shock tower failed after hitting a typical dip on a highway like we all hit, i.e. bridge transitions, pavement transitions. Not a pothole, not a curb, typical highway crappy roads. His (I'll conjecture "defective") shock tower was likely weakened by autocross at lowered ride heights, and then upon a bit of road driving, the final stress occurred that caused fracture.
strut tower failure - Page 5 - Rennlist - Porsche Discussion Forums
Last edited by okie981; 07-24-2021 at 12:19 PM.
#120
Rennlist Member
This. This was not a common problem on the 981 and every instance was due to hitting something. Shame it's not more durable, but it's not a design or manufacturing defect. Don't hit stuff.
That said, I cringe every time I watch a 718 track video where the driver is just pummeling the car over the curbing.
That said, I cringe every time I watch a 718 track video where the driver is just pummeling the car over the curbing.
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Zhao (07-24-2021)