Be aware! Missing Control Arm Nut: Potential Safety Issue

[MY2Ski]

Checked mine and they look OK, s/n 59xx. Do not have a 150 ft-lb torque wrench, but will ask that they check on my SC appointment next week for Frunk Open warnings (third visit for this issue).

 

[Cousin Eddy]

I cant stop looking at the bumper paint miss match with the rest of the car...

Oh, and how is it the OP could not feel the front wheel being so sloppy and the car pulling left/right before the visual effect drew his attention?

 

[TomServo]

I took these when the Mobil Tech was installing my HomeLink, are these the mounting points in question?

The Tech aid they only why he could confirm anything was to jack the car, remove the wheels and check with a torque wrench. But he didn't have time and we both thought they looked fine.

 

[Itselectric312]

*sugar* like this happens on EVERY car, even a high end German Auto like a Benz. Remember the tire recalls and air bags in the past... Yes this is a safety issue, but not only on tesla

 

[imola.zhp]

Shouldn't these have cotter pins in them?

 

[Bueno]

Is it possible that all MYs can be retrofitted with castle nuts instead of these lock nuts? Or would that require all new control arms?

Castle nuts require a hole through the fastener to allow a cotter pin to pass through as shown in this picture. Technically you can do it but I would just verify torque and mark with a product like TSI Supercool 12848 Yellow Warranty Seal Marker.

 

[Dennisis]

Used to be but I don’t believe it’s the current practice with better hardware from what I’ve been able to find. I doubt the two noted on this thread were ever installed or not installed properly, could happen with any hardware on any vehicle.

 

[Dennisis]

Castle nuts require a hole through the fastener to allow a cotter pin to pass through as shown in this picture. Technically you can do it but I would just verify torque and mark with a product like TSI Supercool 12848 Yellow Warranty Seal Marker.

Not just through the nut, through the spindle too so no, can’t just slap a castellated but on there. I’m sure some engineering analysis went into the design.

 

[CJoshuaV]

Has there been an official response from Tesla yet? I saw that at least one media outlet picked up the story.

I was already cautious about going through with my Model Y pre-order, and this outright terrifies me.

 

[mark95476]

1) Suspension arm isn't a soft alloy. It's beefier than the 3's and isn't going to compress or bend allowing the nut to loosen.
2) That's a boot, not a bush.

The suspension arm is soft alloy and one end goes into the rubber bush

 

[mark95476]

I think this lock nut has been used for years on hundreds of thousands of 3's.

Typical of the new Tesla imo. It is hard to contain haste.

 

[mark95476]

Blurry semicircle to the left and marring to the right of the bolt looks like the lock nut loosened and rubbed before eventually falling off. I'd check if the bolt threads have wear (lock nut was installed vs not installed).

I'm not seeing any witness marks on the failed joint.. can you point it out please? Are you referring to the galling inside the nut seat?

 

[mark95476]

One note:

If you ever have an alignment done (wasn't tracking straight, get different wheels and tires), then this same thing could happen. Hopefully your shop is familiar with these lock nuts and don't mess-up.

 

[DS8819]

But he didn't have time and we both thought they looked fine.

Did he give you this in writing? You may need to rely on this in court.

 

[Nuclear Fusion]

Can’t believe people suggested not to report this to the NHTSA. Apologists

 

[MP3Mike]

Can’t believe people suggested not to report this to the NHTSA. Apologists

I thought I read every post in this thread, and I didn't see anyone suggest not reporting it.

 

[DS8819]

Understood. I agree. But 5 cars may be too many with this.

ONE car with a safety critical defect that has the potential to cause a fatal accident is ONE car too many.

 

[DS8819]

If they are on there and look tight against the lockwasher and you don't have any clunking/popping etc, they should be good.

..... Honestly, your honour!

 

[DS8819]

But Tesla is NOT using the Wedge-lock washer. It is using the Nord-lock washer.
The videos show the difference between the two and explain why the Wedge-lock is the better choice for the job.

Maybe they ran out of the wedge-lock, so raided another parts bin in the meantime! A historic ploy by Tesla to keep their figures up it seems.

 

[mark95476]

Generally, anything suspension related needs to be level and loaded before torquing to spec.

(The bolt and nut are steel so I'm going to yank hard clockwise with a wrench to make sure the nut isn't loose.)

The Tech aid they only why he could confirm anything was to jack the car, remove the wheels and check with a torque wrench. But he didn't have time and we both thought they looked fine.