Model X arm control disconnects from wheel at low speed

[ehua329]

Wife was parking her car on Main St. Andover, MA, and suddenly she felt the car was rubbing on something and became immobile. After checking, the front passenger wheel was stuck on a 45% direction with entire body frame sitting on it directly (see picture attached). Initially she thought she had flat tire but police quickly came to scene and pointed out that the wheel (front right) was disintegrated with its arm control. This was at very low speed while trying to turn steering wheel to park the car. Driving the car from home to where the incident happened was no problem, there was no sign of issues and suddenly the issue occurred.

We visited Tesla Watertown in MA today. The service manager was polite but pointed out that there was scratches on the rim and he believed that it must be because she scratched a curbside and caused the wheel to disconnect. I insisted on the dealer to inspect the vehicle before drawing any conclusion. Even though rim may be scratched, nobody is expecting the control arm to break free. Moreover, it seems a latent safety issue: you don't know when it will happen because it is not a result of direct impact like an accident, or as the dealer say, scratching rim and right after that, you get a control arm broken free. This is quite bothering because we kept thinking about the vehicle safety issue, it's our family car and we must make sure it's safe to drive. The dealer was still talking about insurance and they don't want to cover the cost because it seems like we did something to the vehicle causing this to happen - we weren't even thinking about the same thing. Getting the issue fixed is one thing, get to the bottom of the incident is another and more important. I will update on what I am hearing back tomorrow from Tesla Watertown.

 

[RichardL]

I had something similar happen - I had to brake sharply (but not emergency braking) at around 20 mph and there was a huge bang and the front control arm separated from the sub-frame, allowing the wheel to move back into the wheel arch.

Similarly, I was told I must have hit something fairly hard for that to have happened (which I never have and strongly denied). They talked about me needing insurance and also potentially having to replace the wiring harness behind the wheel arch which might have been damaged.

Eventually they fixed the suspension and there was no wiring issue - but I was very un-easy about being blamed for what is clearly a Tesla issue.

 

[dark cloud]

Report it

File a Vehicle Safety Complaint | Safercar.gov | NHTSA

 

[ricohman]

Broken ball joint.

 

[OPRCE]

Broken ball joint.

1. How/where exactly does it break and in what material?

2. Does it only snap off/pop out during parking manoeuvres, but not at high speed, suggesting a design flaw?

3. Is failure related to mileage, i.e. metal fatigue?

 

[CyberShy]

Broken ball joint.

This. Broken ball joint is not a broken control arm.

The ball joint is the connection to the spindle and has been pointed out to be a problem on many Teslas, especially the S.

 

[ricohman]

1. How/where exactly does it break and in what material?

2. Does it only snap off/pop out during parking manoeuvres, but not at high speed, suggesting a design flaw?

3. Is failure related to mileage, i.e. metal fatigue?

From what we can see it appears to have been sheared off. I've broken a few this way. But rock crawling.
As a mechanic I've seen worn out ball joints, but shearing one in a newer street driven vehicle is very rare. Something I have never seen in my days working as a mechanic for a GM dealer.
If the ball joints are failing like this in these cars, they are either undersize or poor quality.

 

[idoco]

I'm going to guess a pothole caused the damage. Based on the snow and what appears to be a bent rim at around 7 o'clock on the wheel.

 

[ehua329]

I'm going to guess a pothole caused the damage. Based on the snow and what appears to be a bent rim at around 7 o'clock on the wheel.

Hi idoco, we recollect not hitting any pothole on the day or in the past few weeks. It happened while she was operating the vehicle normally. Leading up to the event the car was fine driving.

 

[ricohman]

I broke a ball joint when the truck slid off of a boulder and fell about 3 feet sideways.
Mind you this was after 6 years of doing this.
Ball joints are pretty strong.

 

[SSonnentag]

I'm going to guess a pothole caused the damage. Based on the snow and what appears to be a bent rim at around 7 o'clock on the wheel.

Good eye. Yep, the evidence is right there in the photo: scuffed tire and wheel. It could have happened at low speed without the driver noticing too. Perhaps a concrete parking stop buried in the snow; it could have been anything.

 

[ehua329]

I broke a ball joint when the truck slid off of a boulder and fell about 3 feet sideways.
Mind you this was after 6 years of doing this.
Ball joints are pretty strong.

No there wasn't any potholes. We had a police officer on scene and can be a witness. The photo was taken two days later in the parkyard of a towing company.

 

[SSonnentag]

Stress fractures due to glitches in manufacturing are always a possibility.

 

[SSonnentag]

And there is this:

Tesla Suspension Breakage: It’s Not The Crime, It’s The Coverup

 

[ricohman]

Stress fractures due to glitches in manufacturing are always a possibility.

Quality ball joints are subject to ultrasonic testing during manufacturing due to the liability in a failure.
Not saying a glitch can't occur but this many glitches?

 

[ehua329]

Stress fractures due to glitches in manufacturing are always a possibility.

But consumers do not expect hitting a minor pothole or curbside scratching to cause this kind of failures do they? Every consumer does it once in a while.

My point was, how much of a stress is considered abnormal stress cause this to happen, on a 20mph driving zone? Second, latency: car broke not due to any immediate impact. Car was fine on its way to drop off the kids. If the cause of the failure was due to stress which happened some time ago, how best to inspect and find out about this issue ahead of any future incident? That is the key and I would say many consumers want to know about it too.

 

[SSonnentag]

But consumers do not expect hitting a minor pothole or curbside scratching to cause this kind of failures do they? Every consumer does it once in a while.

My point was, how much of a stress is considered abnormal stress cause this to happen, on a 20mph driving zone? Second, latency: car broke not due to any immediate impact. Car was fine on its way to drop off the kids. If the cause of the failure was due to stress which happened some time ago, how best to inspect and find out about this issue ahead of any future incident? That is the key and I would say many consumers want to know about it too.

I absolutely agree. It should be a very rare occurrence, which is why it needs to be reported to the NHTSA. They will have stats and will take action if there seems to be any sort of anomaly with Tesla vehicles.

 

[ehua329]

UPDATE: I RECEIVED THIS EMAIL FROM TESLA WATERTOWN MA. I will post my reply in the next thread.
======================================================================================

Hi Eric,

We have inspected your vehicle and determined that the damage to the right front was a direct result of an impact of the right front wheel with a stationary object. Due to the physical nature of the damage the repairs are not covered under warranty.

Found the control arm and bolt was bent and snapped.

Found the right front wheel has large impact damage.

Found Axle stub separated from front axle shaft.

Found air strut has impact damage.



I will be forwarding an estimate of the repair cost. I would recommend reaching out to your insurance company at your earliest convenience.





Damage to bumper from wheel displacement.

Impact damage to right front tire.

Bent and broken control arm bolt.

Damage to right front air strut.

Axle grease from blown front right axle.

XXXX, Service Adviser
Tesla WaterTown

 

[ehua329]

XXX,

We strongly disagree with your conclusion, and we cannot be liable for the repairment cost.

The ball joint and rest of control arm is meant to be very strong and reliable, so it can survive maximum amount of toque and distortion force during an accident or emergency turn at high speed. A disconnection like such at high speed is fatal.

The picture of the wheel bumper damage is due to disintegrate of the ball joint and as the result wheel scratching the well and pressing on the bumper.

The rest of pictures show exactly the weak design (or potentially mulfunctioning part installed), and consequences of the control arm and/or ball joint breaking free due to a minor rim scratch. Every consumer hits a potholes and scratches their rims once a while. Look at how many potholes there are on the streets leading up to your dealership in Watertown. The question on the table today is why is this enough to cause such a catastrophic failure? Also, there is a latency argument here: The car was fine driving that day, from home to dropping off kids on Main St. when the ball joint suddenly disconnected while trying to park the car. There was no sign or any indication leading up to this event while driving the vehicle prior that afternoon. On the scene, there were no potholes and the vehicle break down location was still some distance away from the curbside (we have police as witness).

Getting the car fixed is one thing, but it is more important to figure out why major failures like such can occur and how to inspect the vehicle and prevent it from happening in the future. Does driving Okay on local street mean it is safe to drive at high speed? If one hits a pothole last month, will the control arm break free in the future? You response did not address our questions.

It appears that you are more concerned about cost and who pays for the repair, while your consumer is more concerned about vehicle safety and future prevention. I strongly disagree that hitting a pothole or rim scratch at severity above is an acceptable cause for control arm disconnection. Honestly I think this is a safety issue possibly due to bad part. To conclude if the relevant parts installed on this vehicle meets particular stress standards, a test needs to be carried out by an independent laboratory.

I will arrange the car to be towed tomorrow.

Regards,
Eric

 

[MP3Mike]

@ehua329 The pictures you posted aren't working, and I would really like to see the damage they were trying to show you.