---

[solidONE]

Looking at the picture it looks like at least there was no frame damage from the incident, just some scrapes in the fender well. Good luck with everything.

[Gixxersixxerman]

Originally Posted by fooddude

Do they still use those "exposed bearings"? ...I believe I read that they use some sort of plastic/poly bearings currently as Standard (ie: when not choosing the optional radial bearing).

In any case...I wonder if it's just a rare occurrence and/or a faulty part (maybe metal quality failure).

I have seen other brands (with a google search) with the same problem - top thread area and nut sheared off on the shaft. It seems like it happens to all brands and is sort of common probability; but, more of a rare type failure. It even happens to "top tier" super high quality and expensive brands - Penske, Tein, Koni and Bilstein...as follows:

The "top tier" brands:
http://www.fitfreak.net/forums/2nd-g...hing-else.html

http://www.axiom1.com/racing/2013091...n_Coilover.php

http://forums.240sxone.com/showthread.php?t=9159

http://forums.swedespeed.com/showthr...ded-tip-broken


And some of the cheaper "generic" brands:
http://www.rx8club.com/series-i-whee...et-use-208381/

http://forums.nasioc.com/forums/show....php?t=2076690

http://g35nyc.com/forums/showthread....e-broken-again

I'm glad you posted these, I was going to find some of these, I've seen the Penske and Tein and Bilstine before, also seen a few BC, and many Stance but I think mainly because they are so cheap(budget) that tons are out there.. I've seen KW and a Ohlins, but the Ohlins happend after a accident, so that can't be put into the same category really.. Just as expensive wheels can break next to knockoffs, a shock can break as well no matter the brand..

[Poodles]

TEIN one looks like the mechanic used a an impact on it, going by the rounded edges on the nut.


Penske setup was from a bad design.


Konis I have no idea on. Given that he had a broken front bumper that was stitched together I'm thinking drift car that hit something...


Bilstein looks like a rattle gun failure as well...


The main failure from the OP definitely looks like a bearing failure caused binding that sheared the bolt off. Kinda surprised to be honest that he didn't notice it was harder to steer or any noise...

[DarkCard]

I just want to state mine were never hit with a impact gun. Handle tools only and a torque wrench. The coils are being sent out tomorrow so ill report back in this thread once I find out more.

Sent from my SAMSUNG-SGH-I747 using Tapatalk

[MikeNYC]

that sucks man how the rest of the car nothing else was damaged right?

[FRSfan111]

Tien was def impact gun. I use an impact to remove but never to install. Always hand tighten then bust out my torque wrench.

[AZFA20]

The torrington style thrust bearings even when completely seized or not even installed should not cause the strut shaft to fail. They are there to prevent spring bind and make your life easier when making coilover adjustments (These ones in the pic though might as well have not even have been there). The shaft will spin freely regardless of the bearings so there should not have been any shaft twist. This issue you are seeing here is not uncommon, unfortunate yes, but it does happen although certainly not on a regular basis obviously. Most of the time you will see failures like this from improper installation (I am not saying that is what happened here but most of the time its what starts the failure). The portions that fail are weakpoints and hollow since this is usually where the dampening adjustment rod runs through the hollow piston shaft. The shafts break like that instead of bend because they are hardened steel.

Hopefully they take care of you but I only post all of this because people let stuff like this scare them from a particular brand when really all of them are susceptible to it due to the hollow and usually thin-walled portion of the shaft at that point. In this case weathering may have also taken its toll and those bearings should not have rusted to that extent but I am not convinced they had anything to do with the rod failure.

[Turdinator]

Originally Posted by AZFA20

The torrington style thrust bearings even when completely seized or not even installed should not cause the strut shaft to fail. They are there to prevent spring bind and make your life easier when making coilover adjustments (These ones in the pic though might as well have not even have been there). The shaft will spin freely regardless of the bearings so there should not have been any shaft twist. This issue you are seeing here is not uncommon, unfortunate yes, but it does happen although certainly not on a regular basis obviously. Most of the time you will see failures like this from improper installation (I am not saying that is what happened here but most of the time its what starts the failure). The portions that fail are weakpoints and hollow since this is usually where the dampening adjustment rod runs through the hollow piston shaft. The shafts break like that instead of bend because they are hardened steel.

Hopefully they take care of you but I only post all of this because people let stuff like this scare them from a particular brand when really all of them are susceptible to it due to the hollow and usually thin-walled portion of the shaft at that point. In this case weathering may have also taken its toll and those bearings should not have rusted to that extent but I am not convinced they had anything to do with the rod failure.

This.

I sell bearings for a living and that style of thrust bearing is a poor choice for a coilover application. But having said that 1) Inspite of the rust they look as though they were still allowing the spring to index and 2) Even if they had siezed it shouldn't have effected the damper shaft at all. There are coilovers on the market that still don't even use bearings like this at all.

The point at which it failed is clearly the thinnest, weakest, part of the shaft. My bet is a small material or manufacturing defect which can happen to the best manufacturers.

[fooddude]

@AZFA20: good point about hollow piston shafts. I wonder if inverted front piston designs would be better for strength? ...since that thin hollow piston shaft would be inside the lower mount/shock body, which would minimize any large movements and forces on that "weak point" by being reinforced and surrounded by more body... and the new upper mount would instead be a solid shaft/mount rather than a hollow piston shaft.

Additionally, I can see how an inverted shock would be a lot safer during similar catastrophes - even if that "weak point" were to break under a pothole/curb, at least it would still be contained inside the lower shock body/mount with all suspension still in place/connected and wheels pointing safely.. instead of having the top break and having suspension parts all over the place and wheels pointing to the moon or behind you or every which way lol.

[fooddude]

All this talk about hollow piston shafts being a weak point is kinda worrying me now about coilovers and adj shocks lol. Maybe I'll just get Bilstein B8 + RCE Tarmac Grey springs. For sure them B8's are gonna be super solid shafts since it's non-adj hehe

[wparsons]

Originally Posted by AZFA20

The torrington style thrust bearings even when completely seized or not even installed should not cause the strut shaft to fail. They are there to prevent spring bind and make your life easier when making coilover adjustments (These ones in the pic though might as well have not even have been there). The shaft will spin freely regardless of the bearings so there should not have been any shaft twist.

This! Those bearings do nothing during normal operation if the stock upper bearing is kept, and even without the upper bearing it wouldn't cause any forces that would shear off the strut shaft. The spring will skip/slide on the upper or lower seat LONG before that happens, and the most it ever rotates is as much as the front wheels are turned.

[Jenson May]

I am a shock tech for Fortune Auto and was directed to this thread by one of our customers via Facebook. To the OP sorry to see this happen and glad you are ok. I put in a call today to our customer service manager and the tech that you spoke to on the phone about this.

The tech said that you specified that the pothole you encountered was very large and that you were sending the dampers in for inspection and analysis. I have already received authorization from my manager to fix your dampers free of charge under warranty.

To answer some of the questions and concerns about this failure:

1. A failure like this has never happened before on our gen 4/5 damper shafts by simply hitting a pothole. Shafts have snapped like this before in major collisions. In a collision snapping a shaft can happen...again not hitting a regular pothole.

2. The torrington needle bearings that you were supplied with are made by NSK Japan. We have stopped using them for roughly a year now because they do not hold up well in very corrosive climates. We will replace your old torrington bearings FREE of charge with our new sealed radial bearings that do not corrode.

3. In no way would the bearings cause this type of failure, furthermore using an impact gun on the shaft should not damage the shaft in anyway.

4. Once we receive your dampers we will test them with our in-house hardness testing machine and then send the shaft out for further in-depth independent testing to try and see what happened.

The shaft supplier that we use is located in Japan and makes very high quality shafts for other Japanese coilover manufactures and OEM damper companies. Our shaft supplier manufacturers these shafts to our rigid specifications. We have compiled a lot of data over the years (racing & street driving) and have come up with a robust hardening spec. We do not skimp on any of the internal components of our dampers and go above and beyond on what we require from our suppliers. As previously stated by some others in this thread, the shafts weak point is at the top of the shaft where it necks down to the threaded section. Since the shafts are hollow (because of the jetting assembly - used to making damping adjustments) we incorporate high end materials, tempering and hardening of our shafts from our supplier. Since I do not have the shaft in my hands its hard to say what really happened. Perhaps it was a defect as things from time to time can fail. We stand behind our products and 5 year warranty 100% and will resolve this issue quickly.

Inverted vs Non-Inverted dampers
Our 500, 510 & 2/3 Way Dreadnought dampers utilize the same shaft and non-inverted design. We do not do this to cut costs but believe a non inverted damper setup is superior in road racing applications because they require less maintenance & have considerably less seal drag. Most top tier suspension manufactures also utilize non inverted designs such as Penske, Moton & JRZ to name a few. I have complete confidence that our shafts are no less robust then the above mentioned companies as we have conducted extensive comparative analysis with our newer shafts vs the aforementioned companies. It is true that an inverted shock can handle higher impact loads but have a lot of performance drawbacks. We actually just started manufacturing inverted dampers for rally applications that see higher loads. It really is a trade off between the 2 designs, both having their strengths and weaknesses.

Hollow piston shafts on adjustable dampers
A few pictures have been posted up by a member of other manufacturers shafts that have snapped. If a shaft snaps under load from a impact gun it is defective plain and simple. The reasoning that the shaft cracked because an impact gun was used is not valid because the upper locking nut has to be secured on with an impact gun.

Warranty
To those people considering purchasing a non inverted adjustable damper, I urge you that this generally not an issue that you need not be concerned with our shafts or other legitimate manufacturers that use this same design. This was either a freak humongous pothole or the shaft was defective. Unfortunately things fail from time to time. As long as the company in question is willing to correct the issue and conduct further research in the subject, you should not be worried. I am proud to say that we are known for our product support and stand behind our warranty 100%.

[Jenson May]

Originally Posted by fooddude

Do they still use those "exposed bearings"? ...I [/url]

We no longer supply or recommend torrington radial bearings because of their ineffectiveness to cope with the elements. If you order our coilovers with a bearing upgrade you are supplied with a Koyo Japan radial bearing that is pressed in to the upper spring perch. This design and bearing is vastly superior to torrington bearings:

Originally Posted by Shankenstein

Does Fortune Auto have a quality assurance procedure to prove out parts before using them? I would think that their operation is "mass production" enough to require it.

Good question, we salt spray test all of our products. Furthermore when we receive parts from our suppliers we test the batches before assembly. In regards to the shafts we conduct surface hardness tests to confirm if they are in the proper hardness range. The shaft supplier also includes a test report on the batch of shafts.

Originally Posted by Turdinator

This.

I sell bearings for a living and that style of thrust bearing is a poor choice for a coilover application. But having said that 1) Inspite of the rust they look as though they were still allowing the spring to index and 2) Even if they had siezed it shouldn't have effected the damper shaft at all. There are coilovers on the market that still don't even use bearings like this at all.

The point at which it failed is clearly the thinnest, weakest, part of the shaft. My bet is a small material or manufacturing defect which can happen to the best manufacturers.

I agree with your point 100% The bearings will not cause this type of failure & that the NSK needle bearings are not a good solution for a daily driven car that will see snow, salt, dirt and rain.

[DarkCard]

Originally Posted by Jenson May

I am a shock tech for Fortune Auto and was directed to this thread by one of our customers via Facebook. To the OP sorry to see this happen and glad you are ok. I put in a call today to our customer service manager and the tech that you spoke to on the phone about this.

The tech said that you specified that the pothole you encountered was very large and that you were sending the dampers in for inspection and analysis. I have already received authorization from my manager to fix your dampers free of charge under warranty.

To answer some of the questions and concerns about this failure:

1. A failure like this has never happened before on our gen 4/5 damper shafts by simply hitting a pothole. Shafts have snapped like this before in major collisions. In a collision snapping a shaft can happen...again not hitting a regular pothole.

2. The torrington needle bearings that you were supplied with are made by NSK Japan. We have stopped using them for roughly a year now because they do not hold up well in very corrosive climates. We will replace your old torrington bearings FREE of charge with our new sealed radial bearings that do not corrode.

3. In no way would the bearings cause this type of failure, furthermore using an impact gun on the shaft should not damage the shaft in anyway.

4. Once we receive your dampers we will test them with our in-house hardness testing machine and then send the shaft out for further in-depth independent testing to try and see what happened.

The shaft supplier that we use is located in Japan and makes very high quality shafts for other Japanese coilover manufactures and OEM damper companies. Our shaft supplier manufacturers these shafts to our rigid specifications. We have compiled a lot of data over the years (racing & street driving) and have come up with a robust hardening spec. We do not skimp on any of the internal components of our dampers and go above and beyond on what we require from our suppliers. As previously stated by some others in this thread, the shafts weak point is at the top of the shaft where it necks down to the threaded section. Since the shafts are hollow (because of the jetting assembly - used to making damping adjustments) we incorporate high end materials, tempering and hardening of our shafts from our supplier. Since I do not have the shaft in my hands its hard to say what really happened. Perhaps it was a defect as things from time to time can fail. We stand behind our products and 5 year warranty 100% and will resolve this issue quickly.

Inverted vs Non-Inverted dampers
Our 500, 510 & 2/3 Way Dreadnought dampers utilize the same shaft and non-inverted design. We do not do this to cut costs but believe a non inverted damper setup is superior in road racing applications because they require less maintenance & have considerably less seal drag. Most top tier suspension manufactures also utilize non inverted designs such as Penske, Moton & JRZ to name a few. I have complete confidence that our shafts are no less robust then the above mentioned companies as we have conducted extensive comparative analysis with our newer shafts vs the aforementioned companies. It is true that an inverted shock can handle higher impact loads but have a lot of performance drawbacks. We actually just started manufacturing inverted dampers for rally applications that see higher loads. It really is a trade off between the 2 designs, both having their strengths and weaknesses.

Hollow piston shafts on adjustable dampers
A few pictures have been posted up by a member of other manufacturers shafts that have snapped. If a shaft snaps under load from a impact gun it is defective plain and simple. The reasoning that the shaft cracked because an impact gun was used is not valid because the upper locking nut has to be secured on with an impact gun.

Warranty
To those people considering purchasing a non inverted adjustable damper, I urge you that this generally not an issue that you need not be concerned with our shafts or other legitimate manufacturers that use this same design. This was either a freak humongous pothole or the shaft was defective. Unfortunately things fail from time to time. As long as the company in question is willing to correct the issue and conduct further research in the subject, you should not be worried. I am proud to say that we are known for our product support and stand behind our warranty 100%.

And this is exactly why I purchased my suspension from you guys in the first place.

My fronts are being sent out tomorow, you will have them during the week as I am on the east coast also. I am also very eager to find the cause of what happened, I have had multiple cars with coilovers and this is a first. Car had no damage other than some minor scraping to the wheelwell. Vehicle was NOT in a collision (Just to clarify )

The service rep I spoke to (I believe Chris?) was very helpful and informative when I spoke to him, so I'd like to say thank you to him too.