Wheel Steering Tie Rod Fell Off on the Racetrack

[wzj998]

Yesterday, I was at the track, and after deep cut the curb of T12(where there's a depression), the tie rod on the left front wheel came off. I noticed the steering wheel was off-center, and when I went over another curb, there was severe shaking, very similar to the "you've got wheel damage" situation in iRacing.

Furthermore, from what I've heard, another person driving a Model 3 Performance had the tie rod on the right front wheel come off after the T10 on the same track(without depression, but the curb can help vehicle turn).

However, it seems there aren't any sturdier aftermarket tie rods available. The current solution seems to be replacing the OEM parts and periodically checking them in the future.

 

[CKwik240]

Looks like the ball joint itself failed. Can the ball joint be replaced? Not that I know if there are better ball joint options either.

 

[Lindenwood]

This might make me add Tie Rods to LCAs and CRs as lists of ball joints that should be considered wear items for hard-use M3Ps.

 

[Collutio]

I'll start keeping an eye on mine now too. I might use a pry bar when I inspect to see if there's any play I can induce with minimal force. I'm not sure how else to check for impending failure. Any better ideas?

 

[CKwik240]

I'll start keeping an eye on mine now too. I might use a pry bar when I inspect to see if there's any play I can induce with minimal force. I'm not sure how else to check for impending failure. Any better ideas?

It would be helpful to see where the OP's ball joint failed. The fracture surfaces can tell us a lot. More often than not, it's fatigue, and that's likely hard to detect as the fracture surface grows over time (load cycles), then suddenly fails when the the stress is higher than intact material can handle.

 

[wzj998]

It would be helpful to see where the OP's ball joint failed. The fracture surfaces can tell us a lot. More often than not, it's fatigue, and that's likely hard to detect as the fracture surface grows over time (load cycles), then suddenly fails when the the stress is higher than intact material can handle.

Here are the photos sent to me by the owner of the modification shop. What information can be obtained from them?

 

[Lindenwood]

The first image looks like the stud actually sheared off the ball. That’s interesting…one would expect a catastrophic ball joint failure would actually have the ball pull out of the socket. That would be like one’s humerus bone shearing off instead of simply dislocating the shoulder.

I am now a bit more inclined to chalk that up to a random manufacturing stress (very much exacerbated by hard use, and not indicative of any real-world safety issue).

The last image would give more detail if they cleaned the grease off!

 

[CKwik240]

The first image looks like the stud actually sheared off the ball. That’s interesting…one would expect a catastrophic ball joint failure would actually have the ball pull out of the socket. That would be like one’s humerus bone shearing off instead of simply dislocating the shoulder.

I agree the failure appears to be in shear, but without being able to see the fracture surface, we can't see if there is any fatigue involved.

The last image would give more detail if they cleaned the grease off!

Agreed. Removing the grease with some Brakleen would be helpful.

 

[Dangerous Fish]

First one I've heard of, but some kerbs can be very hard on suspension. Would be interesting to see the kerbs you're referring to @wzj998
Any photos of those corners available?

 

[MountainPass]

OP, do you have aftermarket control arms in the front suspension? I have seen this before with aftermarket front upper control arms. If it hits the chassis it will bind and the load path will change to the tie rod.

 

[wzj998]

OP, do you have aftermarket control arms in the front suspension? I have seen this before with aftermarket front upper control arms. If it hits the chassis it will bind and the load path will change to the tie rod.

I did indeed replace a pair of control arms separately for camber adjustment on both the front and rear wheels (as shown in the product page, the front control arm is the U-shaped one). The camber of the front wheel is approximately 2.7°. Can you tell from the picture if there is any design issue with this front control arm?

On the other hand, after discussing with the members in the group, some one believes that the impact of the modified control arms is not significant. It could be due to insufficient torque on the screws at the fracture point, which is a possibility considering that I experienced a similar situation with the hub screws on the front right wheel coming loose during my second time using the factory car on the track.(additionally, others have encountered similar situations).

 

[wzj998]

First one I've heard of, but some kerbs can be very hard on suspension. Would be interesting to see the kerbs you're referring to @wzj998
Any photos of those corners available?

This picture shows the curb of T12 that my left front tie rod pressed on before it broke. The video link is model3p天马1:11.233，但转向拉杆断了_哔哩哔哩_bilibili. Currently, there are no English subtitles, but I don't think it affects understanding.

This picture shows the curb of T10 that another person's right front tie rod pressed on before it broke. The video link is: 「下集」蔚来ET5和特斯拉Model 3P改装完毕二度PK_哔哩哔哩_bilibili. Similarly, there are no English subtitles, but you can skip to around 4:07 for viewing. I just asked the author of the video if Jim, the owner of the Model 3P in the video, replaced the front control arms. The video author said no, they are all original chassis parts.

 

[Dangerous Fish]

There are 5 or 6 left hand corners and 2 or 3 right handers on that track where both cars are riding the kerbs and that T12 kerb looks like the worst one to me.
Jim's tie rod didn't break because of T10, it just decided to let go at that point on the track. If it was his left side one like yours then I'd say T12 probably caused most of the damage.

How many laps in total have you both done at that track before the breakages? Not on that day but in total and any other tracks you've been to.

I going to stick my neck out here and say what both these breakages have in common is that both cars are riding kerbs too much and T12 in particular is one I wouldn't want to drop my left wheel into on a regular basis. These are heavy cars and if you keep on pounding over kerbs, something is going to break or bend and it's usually going to be a tie rod as they're the weakest points on any car when a wheel takes a hit.

Have you looked at the rest of the suspension to see what the bushes look like? Any other noises coming from the front or rear suspension?
Also, what do you mean by "hub screws coming loose"? Can you point to a diagram or explain which screws you mean?

 

[wzj998]

There are 5 or 6 left hand corners and 2 or 3 right handers on that track where both cars are riding the kerbs and that T12 kerb looks like the worst one to me.
Jim's tie rod didn't break because of T10, it just decided to let go at that point on the track. If it was his left side one like yours then I'd say T12 probably caused most of the damage.

How many laps in total have you both done at that track before the breakages? Not on that day but in total and any other tracks you've been to.

I going to stick my neck out here and say what both these breakages have in common is that both cars are riding kerbs too much and T12 in particular is one I wouldn't want to drop my left wheel into on a regular basis. These are heavy cars and if you keep on pounding over kerbs, something is going to break or bend and it's usually going to be a tie rod as they're the weakest points on any car when a wheel takes a hit.

Have you looked at the rest of the suspension to see what the bushes look like? Any other noises coming from the front or rear suspension?
Also, what do you mean by "hub screws coming loose"? Can you point to a diagram or explain which screws you mean?j

Jim's vehicle experienced a tie rod failure on the right front wheel, whereas mine broke on the left front wheel.

I've been participating in track activities since the end of March last year, and I've completed over 20 sessions to date (mostly on the track featured in the video, but I've also been to two other tracks). Each session typically consists of at least 10 effective flying laps (excluding warm-up and cool-down laps).

No abnormalities have been found in other suspension components for now.

Regarding the hub screw loosening, it's to illustrate that Tesla's factory torque settings may indeed be insufficient. I experienced loosening of the screws on the right front wheel. You can refer to this video for reference: 特斯拉原厂螺丝均未拧紧 上赛道差点三轮车下场_哔哩哔哩_bilibili. He and I encountered the same situation.

Furthermore, I browsed another Chinese platform, where someone (with an IP address from Australia) mentioned that BMWs with the G chassis also have issues with tie rod failures if driven frequently on the track.

 

[MountainPass]

I did indeed replace a pair of control arms separately for camber adjustment on both the front and rear wheels (as shown in the product page, the front control arm is the U-shaped one). The camber of the front wheel is approximately 2.7°. Can you tell from the picture if there is any design issue with this front control arm?
View attachment 1047657
On the other hand, after discussing with the members in the group, some one believes that the impact of the modified control arms is not significant. It could be due to insufficient torque on the screws at the fracture point, which is a possibility considering that I experienced a similar situation with the hub screws on the front right wheel coming loose during my second time using the factory car on the track.(additionally, others have encountered similar situations).

Can you remove your frunk trim and peer down into the suspension to inspect the top of the control arm? You will find your answer quickly if you see marks from chassis contact!

 

[Dangerous Fish]

You are meaning the wheel nuts? They have to be torqued to 175N/m but more importantly you should check them regularly if you take the car on track. As on any car.

The number of laps you've done on that track with those kerbs doesn't surprise me that something has broken. I have done a lot more track miles in my M3P than you, but so far nothing broke. I check nuts and bolts for correct torque regularly and stay off the bad kerbs wherever possible.

In a race, it's different but on a track day I don't see the point of punishing the car just to get a slightly better lap time.

 

[dbeiler]

Those tie rods appear undersized for the task. Rod diameter is quite small right at the break point. The Model 3 does not have steering rack bushings, common on many legacy vehicles. Rack gets bolted straight to metal frame. The steering system components cannot absorb stress via the (nonexistent) bushings. Very heavy car, combined with lack of rack bushings, small diameter tie rod, and driving over sections of the track that are very taxing to the suspension is going to cause problems.

You may be able to source heavier duty tie rod ends from the drifting community. M14 by 1.5 is a commonly used tie rod size. Certain Nissan S-chassis (S14 specifically) uses that size. Vehicle to vehicle contact is frequent in drifting; the tie rod ends take a serious beating. There are now a seemingly infinite number of suppliers and styles of tie rod ends available. Heim joints, offsets, spacers, whatever you can dream up, it's already available as an off the shelf part. The heavier duty tie rods usually specify a maximum suspension droop allowable. As MountainPass has already pointed out, joints have limited range of articulation. Once the suspension droops or rises to far, the ball joint will shear.