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Found out what’s causing undercarriage composite to break apart

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I just got my M3 LR AWD yesterday. I started hearing random loud sounds coming from the rear. Then I started hearing more overall cabin noise than usual (my sister has an M3 as well). I started looking around the car and looked underneath to find the rear aero shield low to the ground. It appears that there are at least three missing bolts. The drag from acceleration pulls down the shield. If I hit a bump then the shield slams into the ground. I scheduled a service appointment, but they're putting me 22 days out. I'm looking to expedite it because I just got the M3 yesterday and it just seems that more time/driving is just going to make this worse. I sympathize with the OP in that this isn't normal wear and tear. These were manufacturing oversights.

Here's are some short videos I've posted on YouTube.

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I just got my M3 LR AWD yesterday. I started hearing random loud sounds coming from the rear. Then I started hearing more overall cabin noise than usual (my sister has an M3 as well). I started looking around the car and looked underneath to find the rear aero shield low to the ground. It appears that there are at least three missing bolts. The drag from acceleration pulls down the shield. If I hit a bump then the shield slams into the ground. I scheduled a service appointment, but they're putting me 22 days out. I'm looking to expedite it because I just got the M3 yesterday and it just seems that more time/driving is just going to make this worse. I sympathize with the OP in that this isn't normal wear and tear. These were manufacturing oversights.

Here's are some short videos I've posted on YouTube.

inyOlbh.jpg

Bok5fUw.jpg

T0du2bA.jpg

VqvTazf.jpg

Umm...you are also missing your entire rear performance aero shield. (It is held on by 13 bolts) This has to be fixed immediately as it makes the motor, oil filter, and HV connections vulnerable to damage from road debris.

Just take it to Tesla service center directly and have them fix it.

Your rear diffuser needs to be replaced, which requires removal of the entire rear bumper cover (which is not a big deal, but FYI). (It is separate from the painted bumper cover, but the entire assembly must be removed to separate the two pieces.)

Your rear bumper cover is in danger of coming off and doing a lot of damage if you hit a puddle.

You may want to consider just having Tesla pick up the vehicle with a tow truck if your service center is not close.

BTW, the middle bolt hole on the diffuser is a DNI (do not install). There is no longer a threaded hole for it.
 
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I had the exact same issue, May 2019 build. You should take it directly to the delivery/servce center without appointment and ask them to take care of it right away before it gets worse.

I just got my M3 LR AWD yesterday. I started hearing random loud sounds coming from the rear. Then I started hearing more overall cabin noise than usual (my sister has an M3 as well). I started looking around the car and looked underneath to find the rear aero shield low to the ground. It appears that there are at least three missing bolts. The drag from acceleration pulls down the shield. If I hit a bump then the shield slams into the ground. I scheduled a service appointment, but they're putting me 22 days out. I'm looking to expedite it because I just got the M3 yesterday and it just seems that more time/driving is just going to make this worse. I sympathize with the OP in that this isn't normal wear and tear. These were manufacturing oversights.

Here's are some short videos I've posted on YouTube.

inyOlbh.jpg

Bok5fUw.jpg

T0du2bA.jpg

VqvTazf.jpg
 
I just got my M3 LR AWD yesterday. I started hearing random loud sounds coming from the rear. Then I started hearing more overall cabin noise than usual (my sister has an M3 as well). I started looking around the car and looked underneath to find the rear aero shield low to the ground. It appears that there are at least three missing bolts. The drag from acceleration pulls down the shield. If I hit a bump then the shield slams into the ground. I scheduled a service appointment, but they're putting me 22 days out. I'm looking to expedite it because I just got the M3 yesterday and it just seems that more time/driving is just going to make this worse. I sympathize with the OP in that this isn't normal wear and tear. These were manufacturing oversights.

Here's are some short videos I've posted on YouTube.

inyOlbh.jpg

Bok5fUw.jpg

T0du2bA.jpg

VqvTazf.jpg

FYI, here are pictures of the piece you are missing.

Ripped Undercarriage Composite from the rain?
 
These work. You can find them at Homedepot in the section with the specialty screws.


View attachment 409766

I just took a closer look at the pictures from @vadim-modelx on my computer rather than a phone, and I don't see any evidence of any remaining bolt holes (they appear to have been sanded away by the road surface). So the bolts may not do much good at this point! It is hard to tell though - there is no picture from an angle that makes it definitive.

Though, perhaps he is also missing the two further back in line with the center one (the DNI) as well, and putting bolts in those should help pull up the cover I think. He must be missing them otherwise it would not hang down this low. In any case it has to go to the service center immediately since he is missing parts of his car and has a water scoop on the back currently!
 
This is super helpful. I appreciate you all chiming in with tips. I'll let you know what my progress in. Hoping to get this resolved ASAP.

Do let us know. Remember you have a week to return the car. If there are other defects I would just return it at this point for another one. If it is perfect otherwise, this is actually a minor issue and should be able to be resolved in about an hour including the bumper cover removal, diffuser replacement, and reinstall (but they won't have the parts in stock, probably, so it will probably take days or a couple weeks).
 
Here's an update on my Model 3.

May 19, 6:00 PM - I sent an e-mail to the Delivery Experience team and schedule a service appointment via app.

May 20, 6:00 AM - I went to Home Depot first thing in the morning to get those body bolts that Eno Deb and other people recommended. This was super clutch. There were two left at my nearest Home Depot and I super lucky I could find them. This temporarily fixed my issue, but I could still notice more cabin noise and a bit of air drag.

2:00 PM - I end up calling the Service Center to check if they received my request and attempted to elevate the issue. The Service Center representative was a bit reluctant to let me have a faster appointment, which I understand because they're probably overwhelmed. I felt there would be more damage if I just waited, so I was politely insistent. I was unsuccessful and Delivery Experience person. He worked all kinds of magic and had me come in immediately.

4:00 PM - They assess my car and conclude that the part was definitely missing (both front and back). It takes about an hour to wait for an available lift, so they can install it.

5:00 PM - The repair is finished. Deliver Experience walks me through the fixes and says that the missing panels was an oversight. I was previously concerned and upset, but this guy took responsibility and made it his personal mission to fix my problem. I didn't pay for labor or parts in my situation.

In conclusion, I had as good of a customer service experience as could be. It's definitely better than my past experience with dealerships and auto repair shops. I do have concerns about the part quality (same composite material) since I've read some horror stories when I obsessively researched this issue. I'm wondering if some third party could just manufacture a higher quality version (3D scan and print with better material).

Thank you to everyone here for making recommendations! The Tesla community is definitely one of the best things to come out of this.

nOvYlS6.jpg

dLTAWGv.jpg

I think this is the same bolt I purchased ‍♂️

HiKj4Su.jpg


lA3xdY2.jpg

cb2F45g.jpg

yNQFLHr.jpg
 
Here's an update on my Model 3.

May 19, 6:00 PM - I sent an e-mail to the Delivery Experience team and schedule a service appointment via app.

May 20, 6:00 AM - I went to Home Depot first thing in the morning to get those body bolts that Eno Deb and other people recommended. This was super clutch. There were two left at my nearest Home Depot and I super lucky I could find them. This temporarily fixed my issue, but I could still notice more cabin noise and a bit of air drag.

2:00 PM - I end up calling the Service Center to check if they received my request and attempted to elevate the issue. The Service Center representative was a bit reluctant to let me have a faster appointment, which I understand because they're probably overwhelmed. I felt there would be more damage if I just waited, so I was politely insistent. I was unsuccessful and Delivery Experience person. He worked all kinds of magic and had me come in immediately.

4:00 PM - They assess my car and conclude that the part was definitely missing (both front and back). It takes about an hour to wait for an available lift, so they can install it.

5:00 PM - The repair is finished. Deliver Experience walks me through the fixes and says that the missing panels was an oversight. I was previously concerned and upset, but this guy took responsibility and made it his personal mission to fix my problem. I didn't pay for labor or parts in my situation.

In conclusion, I had as good of a customer service experience as could be. It's definitely better than my past experience with dealerships and auto repair shops. I do have concerns about the part quality (same composite material) since I've read some horror stories when I obsessively researched this issue. I'm wondering if some third party could just manufacture a higher quality version (3D scan and print with better material).

Thank you to everyone here for making recommendations! The Tesla community is definitely one of the best things to come out of this.

nOvYlS6.jpg

dLTAWGv.jpg

I think this is the same bolt I purchased ‍♂️

HiKj4Su.jpg


lA3xdY2.jpg

cb2F45g.jpg

yNQFLHr.jpg

Is that last pic the front or back? Have we heard if these are new versions of the parts?