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Found out what’s causing undercarriage composite to break apart
- Thread starter Redrick00
- Start date
silentsnow31802
Member
AlanSubie4Life
Efficiency Obsessed Member
This is truly impressive. You are missing what is called the “M3 Mid Aero Performance” cover. It is typically held on by 13 bolts. I can only see the location of three of them in your pictures easily, and they are all missing. Presumably most of the rest are missing too.
Unless there was sabotage, this is Tesla’s fault.
Separately, your rear diffuser (this is the black plastic bit with the ribbed pattern on the inside, which is attached to the bumper cover (you can’t see the attachments)) is hanging on by just a couple bolts. I would pop the rear plastic covers and make sure those remaining 2 bolts are tightened right now. There are 5 bolts that are missing (at least). Two are shared with the mid aero cover (which are missing as previously mentioned). One goes in that middle missing bolt hole. The last two are a little further back in obvious bolt holes (the middle one of these holes does not have a bolt anymore in recent builds).
This is all Tesla’s fault unless there was sabotage. I would drive to a service center (slowly) and complain. If you cannot avoid freeways I would recommend mobile service for the 5 missing bolts before driving. It is probably possible to get a matching bolt (and washer) from Home Depot for *temporary* attachment for driving to service. You can take out one of the remaining two bolts behind the plastic covers and use it to get the appropriate size and thread pitch bolt at Home Depot, if you want to go that route with your $60k vehicle.
The aero cover does not need to be in place for short freeway runs though it will reduce loads on the rear bumper cover. That’s why that (the diffuser) must be properly attached before driving at speed.
This is an issue Tesla should give you a loaner for or fix immediately. I’m a little concerned the bumper cover may be warped now, but it might be ok. Just have to make sure it has all the attachments (there are two Torx screws and 6 clips in the wheel wells).
This is all something that can be fixed by a pro in less than an hour. Not major.
Your entire rear bumper cover and diffuser is in danger of falling off.
You can use this opportunity to take a picture of the plate on your motor (it is obscured in your picture, the square metallic plate on the left side of the rear motor). What is your build date? Which type of Model 3?
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Bolt installers trying to keep up with the Model 3 production ramp / end of year rush:
Thanks for the information. Build date was December, 2018. Drove slowly to service center this morning using back roads, so we’ll see what they say. Again, thanks for the feedback. Cheers.This is truly impressive. You are missing what is called the “M3 Mid Aero Performance” cover. It is typically held on by 13 bolts. I can only see the location of three of them in your pictures easily, and they are all missing. Presumably most of the rest are missing too.
Unless there was sabotage, this is Tesla’s fault.
Separately, your rear diffuser (this is the black plastic bit with the ribbed pattern on the inside, which is attached to the bumper cover (you can’t see the attachments)) is hanging on by just a couple bolts. I would pop the rear plastic covers and make sure those remaining 2 bolts are tightened right now. There are 5 bolts that are missing (at least). Two are shared with the mid aero cover (which are missing as previously mentioned). One goes in that middle missing bolt hole. The last two are a little further back in obvious bolt holes (the middle one of these holes does not have a bolt anymore in recent builds).
This is all Tesla’s fault unless there was sabotage. I would drive to a service center (slowly) and complain. If you cannot avoid freeways I would recommend mobile service for the 5 missing bolts before driving. It is probably possible to get a matching bolt (and washer) from Home Depot for *temporary* attachment for driving to service. You can take out one of the remaining two bolts behind the plastic covers and use it to get the appropriate size and thread pitch bolt at Home Depot, if you want to go that route with your $60k vehicle.
The aero cover does not need to be in place for short freeway runs though it will reduce loads on the rear bumper cover. That’s why that (the diffuser) must be properly attached before driving at speed.
This is an issue Tesla should give you a loaner for or fix immediately. I’m a little concerned the bumper cover may be warped now, but it might be ok. Just have to make sure it has all the attachments (there are two Torx screws and 6 clips in the wheel wells).
This is all something that can be fixed by a pro in less than an hour. Not major.
Your entire rear bumper cover and diffuser is in danger of falling off.
You can use this opportunity to take a picture of the plate on your motor (it is obscured in your picture, the square metallic plate on the left side of the rear motor). What is your build date? Which type of Model 3?
Forgot to add that it’s a dual motor long range model, not the performance.
AlanSubie4Life
Efficiency Obsessed Member
Did they end up fixing it up for you today or did they give you a loaner?
When I went to get some of these bolts that I was missing, they said they didn’t have any (very odd!)...so maybe you’ll have to wait...
Anyway let us know when it is all fixed up.
A bit late on the reply but yes, they ended
Hey Alan. Just now got around to replying...anyway, they did fix everything so I’m good to go. Great service all around, no issues. They gave me a loaner Model S (I like my M3 way more lol), took about three days to fix. I’m assuming because the parts had to be ordered. Thanks again for the feedback. The car is amazing, really enjoying it! Cheers. - Ricky
AlanSubie4Life
Efficiency Obsessed Member
Great to hear. Hopefully they will get word back to the factory that they need to tighten those bolts. Who knew that would be necessary?
@ricardo_1 I have the exact same problem! Although now that I've taken a look I realize I don't have anything cover both the rear and front motors! Were you only missing the rear composite material?
I got the car a few weeks ago and was hearing weird noises coming from rear from the day I got it. When it snowed the past couple days, there was a clear ground-scraping noise. I looked under, and the black plastic piece under the bumper had been scooping snow off the road and was being weighed down enough to touch the ground. The snow was super compacted in there.
@AlanSubie4Life ricardo showed a pic of his bumper cover coming off at the seam near the wheel well. Do you think there could be any damage there, e.g. the separation is stripping some threading?
I got the car a few weeks ago and was hearing weird noises coming from rear from the day I got it. When it snowed the past couple days, there was a clear ground-scraping noise. I looked under, and the black plastic piece under the bumper had been scooping snow off the road and was being weighed down enough to touch the ground. The snow was super compacted in there.
@AlanSubie4Life ricardo showed a pic of his bumper cover coming off at the seam near the wheel well. Do you think there could be any damage there, e.g. the separation is stripping some threading?
AlanSubie4Life
Efficiency Obsessed Member
The snowpocalypse in Seattle claims a Model 3 victim! Sorry to hear it.
Based on what you say: probably your aero covers fell off nearly immediately because they weren’t properly attached. Stunning, but definitely not unheard of.
Sounds like your rear diffuser was acting as a scoop for the snow since the mid aero cover was no longer present. Absolutely there could be damage (bent brackets, ripped out plastic attachments, etc.). You can probably look once all the snow melts out if you don’t mind sliding under the vehicle (use clothes you don’t care about and a bright flashlight). Sounds like your aero covers were not attached properly, and it likely was not your fault, if you are missing both. You could just not bother with inspection and just take it to Tesla. They should repair it under warranty (whether they will...YMMV). You probably do not need a new bumper cover (good to avoid having to paint match anything), but it depends - there are attachment points in the wheel wells that could be damaged.
It’s also possible that the aero covers were partially attached and the snow finished them off.
One way you can tell is to look for the bolts...if all the bolt/washer combos are still present (13 in the rear, 8+ in the front) it might be “your fault” (drove through a bunch of heavy snow and high centered or whatever - you could certainly argue this should not cause failure though) - if there are a minimal number of bolt/washers remaining, probably not your fault.
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Be glad you don't have sand getting up in the plastic shield. Saw this article on Electrek and posted about it under the undercarriage torn fabric thread first. Amazing amount of sand. Little doubt these are related.
Ripped Undercarriage Composite from the rain?
Ripped Undercarriage Composite from the rain?
I'm considering drilling this hole. Is it still agreed that this is the best spot? And just to confirm, this is slightly on the passenger side of the center line, correct?
AlanSubie4Life
Efficiency Obsessed Member
Yeah, that is about right.
Personally, I would not drill. I would determine if I had a problem by removing the three (you might need to remove a couple from aero under cover as well) bolts and seeing whether there is an accumulation of dirt. Or: modest amounts can be flushed by parking the car pointed downhill and flushing copious amounts of water through, starting from the trunk area, I think.
I'm in SoCal so I'm not anticipating a tremendous amount of dirt there, although I do occasionally drive a short distance on a dirt road, I just don't like the idea of water accumulating. I'll take your advice though and hold off on drilling for now.
AlanSubie4Life
Efficiency Obsessed Member
I'm in SoCal too. As long as you're not at elevation in a place susceptible to icing (prolonged sub-freezing temps seem unlikely in California, even at elevation), the water does just flow out as soon as the car becomes level or slightly downhill. It's really more of an annoyance. I park my car pointed downhill when I wash my car (which ensures the water just flows out) so that I don't have a few cups of water flow out onto the floor of the garage when it levels out (if I am pointed uphill when washing then water accumulates in the rear diffuser). It doesn't take much of a hill to get it to flow out (downhill) or accumulate (uphill).
AlanSubie4Life
Efficiency Obsessed Member
I don’t think it is that big a deal. I think in cases where it is due to missing fasteners Tesla has generally replaced it free of charge. Some people have paid, others have not - depends on the argument they make and the specific situation. I suspect that if Tesla got a lot of these immediately after a heavy rain they might be less inclined to replace them under warranty...because if you drive through a huge puddle it can definitely cause damage, and that is really not Tesla’s fault (though you could make an argument for poor design, at some point enough water at sufficient speed will damage any vehicle).
If there are bolts missing Tesla really has to replace it under warranty. All bolts should be present and they should not loosen.
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