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Question about stress cracks on rear glass. What would you do?

Question about stress cracks on rear glass. What would you do?

Hey all. I was washing my car and noticed 2, US quarter sized, "star burst" shaped, cracks. They're in the very front of the rear windshield right behind the center support beam. They're hard to see and I only noticed them cause I stood on a stool to wash the top. They're on top of the wide black border around the glass, adding to its camouflage. The question is, I have the original glass with the cool red tint in the rain and I'm unsure if I should go through the hassle of replacing it. Should I have Tesla replace it and risk leaks/sound issues or should I keep the original to keep the cool factor?

vmulla | December 9, 2019

Can you not fill them with resin and get it repaired?

EPwolf | December 9, 2019

If I believe there are cracks in my glass, I would have it replaced. "Cool" red color is no reason to live with a potential problem. Cracks can propagate at the worst times. I would also not hesitate to have Tesla replace the glass, and leaks/noise would not be a concern for me.

bp | December 9, 2019

Just out of curiosity, what year is your car, how many miles, and have you ever mounted anything on the roof (including factory cross bars)?

Magic 8 Ball | December 9, 2019

Hello I am anonymous to you and I say doooooo eeeeeet.

Lorenzryanc | December 9, 2019

Its a 2018, April 2nd delivery with ~13k miles. VIN 7400. Never anything on roof and the crack seems to be from below. My nail can't catch on anything so I don't think I can resin it.
@M8 and EP... I rely on anonymous interwebs people to inform my life. I think I SHOULD, but wanted to see if I'm crazy to go through with it and change it... I shall miss my rubys.

pg_bangalore | December 9, 2019

I had a Rear window crack in July 2019 and now again i got another crack in Dec 2019. And you have to work with the tesla service center only to have the rear glass replaced. We will have to pay initially and then re imbursed by the insurance company. Not sure why this crack appears. I park my car inside the garade at home and outside while at work. BTW we stay in connecticut. Is it related to temparature.?? should i put car cover all the time ??
Any help in preventing it further times are really appreciated.

apodbdrs | December 9, 2019

If the car is still under warranty, have Telsa replace it ASAP!

apodbdrs | December 9, 2019

Tesla not Telsa!

Lorenzryanc | December 9, 2019

@pg
My assumption is that this should be covered by warranty, not insurance, but Tesla has reached out and they need to verify before they know who'll pay for it.

Bighorn | December 9, 2019

Have you been hanging out with Franz von Holzhausen?

sbeggs | December 9, 2019

@Bighorn,
T hee!

coleAK | December 9, 2019

Sounds like the cracks are from rock impacts. Go to a reputable auto glass repair and see if they can be repaired. If so consider it, if not replace the glass.

DuckDuckEv | December 9, 2019

I had the same issue with my M3 after around 8000 miles, Tesla did replace the rear glass for free.

Lorenzryanc | December 9, 2019

I WISH I was hanging with Franz :) @cole I doubt these are cracks from rocks, although, they kind of look like a windshield chip. They're on top of the car and there's no chip or anything. I can't catch anything with my nail so the crack is from below and they're about an inch apart. I'm still standing by for Tesla's response on how to find out if its covered by warranty.
Maybe Franz stopped by when I wasn't home...

DuckDuckEv | December 9, 2019

I was told the crack was coming from the rear glass defroster lines, looks like they had issues with these glasses and got the upgraded ones out a while ago.

Lorenzryanc | December 9, 2019

Interesting. I don't think these cracks are near a defroster. They're about one inch back from the leading edge. Not on the clear glass, but above the thick black boarder.

bjrosen | December 9, 2019

You need to have the glass replaced, don't know if it's a warranty item but in my state, MA, glass is covered by insurance.

coleAK | December 9, 2019

Energy hits the surface and dissipates through the back. It’s very common to have an impact that dosn’t damage the impact point on the outside then blows out the back of the glass. I consider myself somewhat of an expert on broken windshields, I get a major chip/break in at least one of our vehicles windshield every year. They don’t salt the roads in AK and just use massive amounts gravel/cinder when we get mast ice like today (40F and raining on top of 2-4” of solid ice).
Ever seen a BB/pellet hole in glass? Small hole on impact side massive hole on exit.

Lorenzryanc | December 9, 2019

I have seen the BB hole... it's kinda cool but yea, the big chunk out the back end. So how does one know if it is impact related vs stress? 2 reasons I ask. 1st, I'm having a hard time seeing how an impact on the top can make 2 very similar cracks on the top of my car and 2, I'm not paying ~$700 to change it if I'm paying.

coleAK | December 9, 2019

I would ask Tesla, I did. We have an odd crack like you describe on the side of our windshield directly over the bonding and another on the roof directly over the bonding. Tesla looked at ours and said rock impact so I had them drilled and filled.

Magic 8 Ball | December 9, 2019

Let’s see pics?

Lorenzryanc | December 9, 2019

I don't have an imgur, but I'll set one up... incoming

Lorenzryanc | December 9, 2019

"https://i.imgur.com/RYWrI60.jpg"

"https://i.imgur.com/GHTlfqh.jpg"

Image from the side for orientation and top for scale.

Magic 8 Ball | December 9, 2019

Impact stars, for sure. Something got kicked up and landed on your glass.

gmr6415 | December 9, 2019

@Lorenzryanc, looking at image #2 (https://i.imgur.com/GHTlfqh.jpg), it's clearly evident it's from the stress of the garage door opener that you have mounted inside your car. ;-)

coleAK | December 9, 2019

Impact without a doubt.

TeslaTap.com | December 9, 2019

@gmr6415 - Best laugh of the day :)

Pepperidge | December 9, 2019

Shooting stars, I am sure.

Lorenzryanc | December 10, 2019

That opener took forever to install! You know how hard it is to screw into glass without it cracki…. umm... ;)

I agree it does look like an impact from a small rock on the front windshield would make, but every one of those I've seen (only a few admittedly) has always had a small chip in the middle, this is completely smooth.

Regardless, as who can say if something happened when I wasn't with the car or while wife was driving, @cole, you said they can drill and fill? Like drill a hole in middle and force resin into the crack? I'd much prefer that fix especially since you can't see these stsrs from below and can only see from above when standing on a stool (or 6'5" and taller).
Thanks for all your insights... and jokes! :D

sheldon.mike1010 | December 10, 2019

Those need to be drilled and filled by a glass pro ASAP

WW_spb | December 10, 2019

I wouldn't let anyone but Tesla to mess with it.

coleAK | December 10, 2019

Yes I watched them do it. Drilled to smooth out then filled with some kind of resin.

coleAK | December 10, 2019

I’ll add you can still see where they are but are hopefully more stable. Had that done last spring and they haven’t cracked more.

coleAK | December 10, 2019

I’ll add you can still see where they are but are hopefully more stable. Had that done last spring and they haven’t cracked more.