Frame Failure called "Normal Wear and Tear" by Tesla Service

[Black306]

Sounds like an opportunity for someone to come out with an aftermarket support bracket. '03/'04 Mustang Cobras are notorious for breaking rear differential covers cause of the torque they make. One solution is an aftermarket bracket that bolts over the factory cover. I can see a steel brace wrapping around the sub-frame on Teslas to support the factory DU mounting tabs.

 

[MP3Mike]

Thought about it, they said they might void DU warranty if i go that direction

Technically they can't void the DU warranty unless they can prove that the work you did caused the failure...

 

[croman]

Technically they can't void the DU warranty unless they can prove that the work you did caused the failure...

Yes it's circular. If it was the DU, it would be under warranty to begin with.

 

[Zextraterrestrial]

I have exactly the same symptoms. At first i thought it is drive unit, cause one of my previous units made similar noises before it was replaced. But unfortunately it is subframe mount. 78k miles on the clock.

I thought i have a case of their fault cause i had 2 drive units replaced during 2019. That means frame was unscrewed and tighten up two extra times... but no luck.
i guess i have to man up and pick up this bill

Ya. I would 100% put the DU at fault for the subframe failure!!!
there is a slip angle sensor set up in the DU to minimize gearlash slop but mine had so much play & the software didn't flag it before it broke the motor mount.
then the DU actually completely striped the gears within a couple of weeks of the subframe replacement.
If you ever have a little play between regen and throttle this could happen. never seen in in D but only in Reverse so not sure how they can say it is abuse or something?

 

[Huachipato]

Sounds like an opportunity for someone to come out with an aftermarket support bracket. '03/'04 Mustang Cobras are notorious for breaking rear differential covers cause of the torque they make. One solution is an aftermarket bracket that bolts over the factory cover. I can see a steel brace wrapping around the sub-frame on Teslas to support the factory DU mounting tabs.

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Having moved from a Cobra to the Tesla, I can say the issue is different. The main issue with the Cobra was wheel hop, the wheel rapidly gaining and losing traction causing all kinds of stress on the rear differential and half shafts. Reinforcing the rear differential was helpful in making the rear cover more durable. The other issue was crazy hard launches with way more grip than what it was designed to be used for in stock form (drag strip with drag wheels). I only point this out cause my Tesla is crazy smooth in putting the power to the ground in comparison to the primitive (yet intoxicating fun) way the Cobra put power down. I've never felt the wheel hop or anything other amiss in the way the Tesla propels it's way forward.

As a side note - that issue as far as I could tell was never seen as a defect either - just owners taking the Cobra beyond the stock limits it was designed for.

I myself did the reinforcement of the rear cover and later learned the best solution was a Ford Racing cover. That said - it would be interesting if there was a way to reinforce the "engine Mount" with additional bracing.

 

[Naekuh]

problem i see is its a alu frame right?

The simplist fix would be to put a stronger mount.
But the Alu frame is preventing all those from not being allowed due to either disimular metals and long term corrosion, or the frame itself can not handle the sheer stress of the mount, and a mount sheering is better then the frame ripping in half.

 

[Black306]

Having moved from a Cobra to the Tesla, I can say the issue is different. The main issue with the Cobra was wheel hop, the wheel rapidly gaining and losing traction causing all kinds of stress on the rear differential and half shafts. Reinforcing the rear differential was helpful in making the rear cover more durable. The other issue was crazy hard launches with way more grip than what it was designed to be used for in stock form (drag strip with drag wheels). I only point this out cause my Tesla is crazy smooth in putting the power to the ground in comparison to the primitive (yet intoxicating fun) way the Cobra put power down. I've never felt the wheel hop or anything other amiss in the way the Tesla propels it's way forward.

As a side note - that issue as far as I could tell was never seen as a defect either - just owners taking the Cobra beyond the stock limits it was designed for.

I myself did the reinforcement of the rear cover and later learned the best solution was a Ford Racing cover. That said - it would be interesting if there was a way to reinforce the "engine Mount" with additional bracing.

This is neither the thread nor the website to bring up Cobra specifics. But I am pleased to see someone else has been exposed with and agrees with what I’m suggesting for a Model S. I’d be curious to see what someone comes up with.

PS. I too initially went with a brace [Billetflow] but then switched to a Motorsports cover. Had to pull the cover off anyway to fix a leak; another common issue.

 

[rickyjb]

problem i see is it's a alu frame right?

The simplest fix would be to put a stronger mount.
But the Alu frame is preventing all those from not being allowed due to either disimular metals and long term corrosion, or the frame itself can not handle the sheer stress of the mount, and a mount sheering is better then the frame ripping in half.

correct me if im wrong but i think tesla have already revised the rear subframe , i was told this is why mine took so long to arrive as they were trying to get hold of the right one . It makes sense to have the mounts be a failure point rather than the frame , but only if they could fix the mounts instead of replacing the whole frame .

 

[PhilDavid]

correct me if im wrong but i think tesla have already revised the rear subframe , i was told this is why mine took so long to arrive as they were trying to get hold of the right one . It makes sense to have the mounts be a failure point rather than the frame , but only if they could fix the mounts instead of replacing the whole frame .

Do you know what year and month they began shipping cars with the redesigned/stronger sub frame part? I guess this is especially useful for those with performance cars.

 

[Naekuh]

Do you know what year and month they began shipping cars with the redesigned/stronger sub frame part? I guess this is especially useful for those with performance cars.

i do not think tesla would of disclosed that to him.
If they did, then he should share it with these guys where tesla stated they revised the subframe, as it can be used as evidence in court that they acknowledged it as being bad, and revised it.

Also cant really accurately estimate as well, as the people posting have cars dating from 2012-2015.
So we dont really know if the new revisions are good, as time was not put on the part as those from the people who posted.

But if we had to pick a date, id say its probably within the iteration of probably when the 60/90 got its refresh to a 75/100, because from what i have picked up on the forum, a 90 is like the blacksheep of Tesla, and the 100 was the fixing of everything.

 

[rickyjb]

o I didn't think to ask at the time . I was told by Tesla there was a delay finding the right revision of the subframe for my car 2014 p85 .
Could have just been a excuse for waiting on parts.

After some digging on eBay looking at serial numbers and part numbers for rear subframes
It looks like there is only 1 type regardless of large or small drive unit. Thay all look identical and have the same part numbers all with rev 00a.

Strange how it only affects rear wheel drive cars , mostly the p85.

 

[PhilDavid]

I assume (hope) the ESA warranty would cover this. Is that a correct assumption?

 

[Ssvladi]

ESA will cover it. I dont have ESA, but they told me that thats normal for subframe to fail......Rep made a parallel with clutch disc on his ICE car....That was a highlight of the convo.. Trying to get in touch with any supervisors or managers right now. Since my DU was replaced twice during 2019 calendar year, they could've inspect subframe for wear and tear since its a moving part in their book..

 

[Tex SS]

I've joined the ranks of those P85 owners with a subframe break. It occured this Saturday while driving my 2013 on the highway at about 70mph. Let off the accelerator and felt a thud. When I again applied power I felt and heard a corresponding clunck. I dropped it at the SC as quickly as possible afterward and received the same explanation of normal wear and tear. The part number I am getting is an "L" variant and from what I can discern the early '12 and '13 models had an "A" variant. I spoke with some experts who said that this is mildly common on the old S, but a non-issue for newer. So far at 75,000 miles and no other issues. Hope this is it for a while. Seems like I got it into the SC before any other damage could be done based on the costs some of you have shared. All in is $2300.00 for full replacement.

 

[Tex SS]

I did confirm visually the broken subframe pictured was an "A" variant. The replacement was an "L".

 

[rickyjb]

View attachment 503804 I did confirm visually the broken subframe pictured was an "A" variant. The replacement was an "L".

sorry to hear it , how long was the car in for ?

i still find it hard to believe how they justify this as ware and tear when most of the failures are p85's and all of the pics ive seen are broken in exactly the same way . the frame and mounts were probably strong enough for the standard motors but clearly not for the performance ones.

 

[troymccas]

Same thing just happened to me on a 2014 Model S P85+ with 80k miles. Broken rear subframe - they said is was due to excessive acceleration Cost to repair $3k.

 

[Battpower]

Same thing just happened to me on a 2014 Model S P85+ with 80k miles. Broken rear subframe - they said is was due to excessive acceleration Cost to repair $3k.
View attachment 504910 View attachment 504910 View attachment 504911 View attachment 504910 View attachment 504911

Yeh,

Standard, Performance, P+, insane, ludicrous...... and you broke it because you tried 'excessive'. What did you expect?!

 

[Tex SS]

sorry to hear it , how long was the car in for ?

i still find it hard to believe how they justify this as ware and tear when most of the failures are p85's and all of the pics ive seen are broken in exactly the same way . the frame and mounts were probably strong enough for the standard motors but clearly not for the performance ones.

Four days, but the acual work took about four hours based on comms from SC. Looking at the assembly I wouldn't expect much more than that. Clearly the original subframes were not robust enough for the added torque.

 

[HeyMike]

I have the same thing happening to my 2012 P85 9 months after the drive unit was replaced. I wonder if the service technicians are over-tightening that mount bolt and causing extra stress on the sub-frame flanges. It just seems odd that most people seem to have the drive-unit replaced and a short time later the flanges break.