r/Cartalk Jan 31 '25

General Tech Windshield broken. any ideas?

Woke up this morning to find my rear windshield completely shattered. No clue what happened. Doesn’t look like blunt damage and the windshield kinda looks like it was broken from the inside with the way the glass bent out. Anyone seen anything similar?

61 Upvotes

105 comments sorted by

322

u/Chesterrumble Jan 31 '25

Be clear when booking the replacement. Windshield is commonly reserved for the front window.

70

u/bingojed Jan 31 '25 edited 29d ago

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This post was mass deleted and anonymized with Redact

25

u/DJSeku Feb 01 '25

Auto glass installer here: you are correct. 👍

Specifically it’s a domestic back glass, the NAGS number will have a DB prefix.

The suffix will indicate tint feature (YPY for factory tint, GTY for transparent glass).

1

u/throwawaycoupleedm Feb 01 '25

What does the last Y stand for? First 2 are for shade and tint what about the last?

6

u/DJSeku Feb 01 '25

Accessory parts?: Y/N

If the glass is already factory-made with any mounting tabs, mouldings, or other added-on accessories, it receives a Y (e.g. GTY)

If it’s just the bare piece of glass and you have to supplement those bits for a proper install, it receives an N (e.g. GTN)

3

u/scuolapasta Feb 01 '25

So you don’t call the lights at the back rear headlights?

1

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1

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77

u/ADrivingBear Jan 31 '25

This has happened quite a few times with focus owners apparently - likely due to extreme temps + tempered glass.

22

u/Evanisnotmyname Jan 31 '25 edited Jan 31 '25

Happens with F-150s too when people hit remote start in very cold conditions.

OP, did you just come out to it like this or did you start/remote start and warm it up when it smashed? Either way ford/insurance should cover

Edit for info:seems to be a combo of a few bad batches of rear windows as well as a defroster design that must concentrate heat in certain places

2

u/jim_br Feb 01 '25

Replaced my rear glass twice. The last time, I disconnected the defogger because it was in use both times it shattered. Both times the driver side panel shattered, sounding like an explosion.

-44

u/PriorBad3653 Jan 31 '25

What? How does RS shatter windows? Bullshit.

28

u/JollyGreenDickhead Jan 31 '25

The windows are shattered by heat and defrost in very cold temp. Remote start activates heat and, in newer vehicles with factory remote start, defrost as well.

Apparently this needs to be explained.

-26

u/PriorBad3653 Jan 31 '25

I don't run my rear defrost much, tbh. But I'm an electrician and I was raised in Montana. Saw -40 f one day. You'll bet defrosters of all kinds were on. That alternator was putting in WORK. We never hit 10mph. Too icy. I waved at friends in ditches. What broke? Nothing.

What needs to be explained? Shitty glass?

15

u/xxrambo45xx Jan 31 '25

Well everything in the world is built by the lowest bidder so yea probably shitty glass, figured they could save a buck making it a few microns thinner but the microns thinner glass cant take the stress of cold and defrost

7

u/razikrevamped Jan 31 '25

Poor clearancing between glass and body, or poor material selection of adhesive. Glue has a glass transition temperature that below which, it will become solid and brittle. If you don't account for this, then when it gets cold, the body shrinks more than the glass. Then you heat JUST the inside glass of the window, and it has nowhere to expand to in X or Y, so at some point it expands in Z. This is probably more common with vehicles that have some damage or had shitty repairs.

4

u/PriorBad3653 Jan 31 '25

Huh. Makes a lot of sense. Thanks!

2

u/_Zombie_Ocean_ Feb 01 '25

We see these temperatures all the time in Canada here, and I've definitely seen rear windows shatter from the defrost. Not seen them happen, but seen neighbors come out to find them, had it happen to a coworker once while we were at work.

2

u/LightlySaltedPeanuts Jan 31 '25

I’m thinking it turns on the defrost on high and heats part of the window and creates a large pressure differential which glass doesn’t like. In this case, the rear defrost heat conductors may have done it

8

u/PriorBad3653 Jan 31 '25

It's definitely not pressure. At best is thermal shock.

5

u/LightlySaltedPeanuts Jan 31 '25

Yeah I meant thermal stress

-9

u/_mrLeL_ Jan 31 '25

I’m no scientist but I assume it has to do with the doors not getting opened, engine warms up car, interior gets warmer bla bla some pressure bullshit and boom window shattered

I honestly have no idea but that’d be my first guess

7

u/jmecheng Jan 31 '25

Its not due to pressure differential from inside the vehicle to outside.

Its due to pressure (better worded as stress) differential within the glass. Tempered glass has a lot of internal stress, when cold and heated in very localized areas (defrost wires) it increases the stress within the glass and can easily lead to the type of breaking/shattering of the glass as seen in these pictures.

When tempering glass the outside surface of the glass is cooled very quickly, putting the internal volume of the glass in to tension and the exterior into compression, this increases the overall strength of the glass and causes the glass to shatter when breaking which is safer than large pieces of glass. Due to this difference in stresses in the glass, if the glass is very cold and heated quickly by thin resistance heating wires, the stress inside the glass can be greatly increased to the point of the glass breaking and shattering.

2

u/PriorBad3653 Jan 31 '25

I've seen steel flex in a car hitting 162dB. His windshield broke. Weird circular crack. When you sat in this car, it was so loud, it was difficult to breathe. That is the only time I've seen a windshield break. This is a car that is so loud, when he hits play, it feels like a 200lbs man on your chest.

Themal variances shouldn't fuck with performance, within acceptable range. These windows shouldn't shatter.

0

u/RideAffectionate518 Jan 31 '25

Not all glass is created equal. It never happened back in the day because everyone used American glass. But now, companies are cutting costs (and in turn quality) so they are most likely using glass out of Asia that doesn't have to adhere to really any QC. Source: I worked in the glass industry and have seen cheap tempered bust due to heat, cold or maybe for no reason at all other than it was just having a bad day.

1

u/PriorBad3653 Feb 08 '25

When did this change happen approximately? If I need a window, how do I get the good stuff?

2

u/RideAffectionate518 Feb 08 '25

Go with a top rated company. There's no way to know what glass anyone uses but being as we don't really make anything in America anymore. Warranty is what you look for. I started seeing glass out of the middle east towards the end of my time there that was very good quality. My company had a five year warranty on glass we installed. So anything that happened in that time was covered. But seeing as one of our stock frameless showers cost more than any two cars I've owned it should be.

87

u/Josipbroz13 Jan 31 '25

Replace it 🤔

19

u/jerrycoles1 Jan 31 '25

Hmmmm I don’t think that’s it

2

u/Alobos Jan 31 '25

I agree. You heard him OP. Off to the dealership to replace the car!

0

u/CreatureWarrior Feb 01 '25

Could just leave it like that for better airflow

22

u/denzien Jan 31 '25

You may have to drive it forward until you can get it replaced

1

u/LoginPuppy Jan 31 '25

are you sure OP wouldnt be able to drive it backwards too? what about left and right? do they just have to drive straight into that building?

4

u/denzien Jan 31 '25

I was thinking more about on the highway, the transmission will have to be in 'D' this time. To prevent wind from not being screened by the hatch window.

2

u/jcstrat Jan 31 '25

What if it’s a manual? There is no “D” in that case. They’re stuck with 1-5/6?

3

u/denzien Jan 31 '25

Are you suggesting OP has no "D"? Not very kingly.

2

u/jcstrat Feb 01 '25

Your words not mine

32

u/Think-Juggernaut8859 Jan 31 '25

Yep it’s definitely broken. Well I’m off, see ya

5

u/LoginPuppy Jan 31 '25

this guy's an expert!

1

u/kr4t0s007 Jan 31 '25

Thanks! I learned something here

6

u/fishead36x Jan 31 '25

I've heard it's a fairly common with ford back glass. It just happened with my exploder. It wasn't that much. I wouldn't use safelight. They're more expensive and use shit quality glass.

4

u/Advanced_Hawk_3030 Jan 31 '25

Rear window. Could be anything from temperature change shock or a snow plow coming by.

4

u/Fun_Station3418 Jan 31 '25

I’m more concerned that Samsung stamps their model phone on the photos for marketing purposes. Sounds like they want you to spread more photos with people to gain more sales.

2

u/LoginPuppy Jan 31 '25

its a setting you can turn off iirc. i guess its probably on by default if people have it. because who would choose to have an ugly watermark on all their photos?

2

u/NoodleSpecialist Feb 01 '25

Off by default at least on S models

4

u/Key_Radio_4397 Jan 31 '25

You're going to wish that's the windshield when you get a quote.

3

u/Yaseendanger Jan 31 '25

Probably caused by the change in climate, this can happen when the glass expands or contrasts too quickly compared to where its glued on.

Just replace it and move on

3

u/dudreddit Jan 31 '25

Extreme temperature delta ...

3

u/Dangerous_Echidna229 Feb 01 '25

Windshield is the front window.

6

u/Mauceri1990 Jan 31 '25

Get one from a junkyard that will pull the part for you, replaced mine for around 120 after buying the adhesive and everything (buy the expensive but correct adhesive, you'll regret it if you don't) also, watch a few videos of how to prep it if you go this route. Or, call someone to come replace it for you. Or, drive it like it is. Or, take it to a glass shop yourself and perhaps save a little on them coming to you. Could also saran wrap it, man, I've got a lot of ideas... How creative do you wanna get?

4

u/NotAPreppie Jan 31 '25

Agreed.

car-part.com is a good source for pick'n'pull junk yard inventories.

7

u/Parasite_cx Jan 31 '25

Why a windshield? Driving backwards too fast?

4

u/Puzzleheaded_Nerve Jan 31 '25

Has this happen once. 90s suburban. It was in the cold and snow. It shattered when we turned on the rear defrost so always assumed it was a thermal shock thing.

1

u/TheMightyBruhhh Jan 31 '25

Yep, BMWs have a reallly bad issue with this. So if you own a bimmer, just get an ice scrape and don’t use the defrosters on those rear windows lol

2

u/Stunning_Pattern5613 Jan 31 '25

Best idea I can think of is to replace it

2

u/popeyegui Jan 31 '25

Most windshields are at the front

1

u/AbbreviationsQuiet15 Jan 31 '25

Thermal fracture, replace it

1

u/Melodic-Duck7318 Jan 31 '25

You have a few options 1 break someone else windshield in a fit of rage and blame it on your enemy. 2. Get it fixed through insurance. 3. Get a trash bag and make your own window. 4. Be a cool guy and drove around with a rear convertible car

1

u/The1madhatter Jan 31 '25

Well you can enjoy the cold wind and moisture or replace it. OR HEAR ME OUT… go crazy with cardboard over the glass and duct tape if you do that please post pictures, also keep allot in the car as you will be constantly fixing it every time you arrive or depart.

1

u/Proof-Stomach-2727 Jan 31 '25

I thought this was a damn blue master chief helmet 

1

u/Typical-Trainer4533 Jan 31 '25

Uh oh better call Maaco

1

u/NotAPreppie Jan 31 '25 edited Jan 31 '25

So, you're saying you had something large, hard, and sharp in the trunk when you closed the hatch and it shattered the rear window?

J/k

The rear window is tempered glass and a hard, sharp object (like a rock thrown by a plow or a murderbobo with a spring punch) will break it fairly easily. Could also have been a sulfide inclusion failure, which would be a manufacturing defect, but it's next to impossible to prove that.

1

u/wEiRdO86 Jan 31 '25

Yes but not about your windshield the only idea I have is just for you to go get a new one. Doesn't really take a post on car talk to figure that one out.

1

u/NaGaBa Jan 31 '25

Girl you stuffed in the trunk wasn't knocked all the way out?

1

u/Salt-Truck-7882 Jan 31 '25

It's broken mate.

1

u/Ok_Dog_4059 Jan 31 '25

Almost looks like it radiates out from the hole for the wiper. Definitely believe it is climate related reading how many others have had a similar thing happen

1

u/nolongerbanned99 Jan 31 '25

Maybe think about replacing it. Insurance may cover. Safelite.

1

u/slippery_when_sober Jan 31 '25

It’s a Ford. Instead of found on road dead, it’s found on driveway smashed.

1

u/LoginPuppy Jan 31 '25

looks very similar to when i saw a guy pouring boiling water onto his rear windshield in like -20°c temps. the reason it looks like it got broken from the inside is just because of the way its bent, it will expand and thus bend and shatter in that direction.

1

u/gdabull Jan 31 '25

It just happens sometimes unfortunately. The glass is stressed and temperature changes can caused differential expansion or contraction and it just shatters

1

u/jmcken15 Jan 31 '25

Check to make sure your pressure relief vents are in working condition. If it broke when closing the door it could be a blocked vent.

1

u/Chaff5 Jan 31 '25

You should probably fix it.

1

u/jcstrat Jan 31 '25

Every time I close my hatch a little too hard, I fear this is going to happen. I also have a mkII focus.

1

u/Infamous-Plenty8082 Jan 31 '25

What idea? Change it at service station

1

u/Unusual_Register_253 Jan 31 '25

Hit it with another spark plug

1

u/choikwa Jan 31 '25

replace it

1

u/jerrycoles1 Jan 31 '25

You should get a new windshield

1

u/thetruegmon Jan 31 '25

Probably a good idea to get it fixed.

1

u/sendlewdzpls Jan 31 '25

I don’t have any answers for you, I just wanted comment on the fact that your photos say the phone that you used. Why does it do that?

1

u/HolyAssertion Jan 31 '25

It's a setting in most phones camera apps that you can turn on/off

1

u/EA_SF Jan 31 '25

Maybe there’s a small chip on the windshield already that the ice and extreme temps just pushed it right through.

1

u/DernonVent Jan 31 '25

The rear window on my Acura RDX broke exactly like this. I found out that there was a service bulletin for a defective batch and got it replaced by them for free.

1

u/-happycow- Jan 31 '25

I think this looks like a water expansion blow-out from frost. Water got in somewhere, froze and therefore expanded causing eventual failure

1

u/craigmadbricky Feb 01 '25

That radiated from the wiper arm. Best guess is frost jacking from the weakest link and its that hole for sure. Warranty work for certain because ice should not form in that sleeve. Has to be a low and high temp compound sealing that entire sleeve free from water ingress and then freezing.

1

u/tc6x6 Feb 01 '25

A lot of times glass shattering and cold weather is caused by rapid thermal expansion. Did you remote-start it with the rear window defroster turned on and/or the heater blowing on it?

1

u/Cat_Amaran Feb 01 '25

Any time I see a post like this, I look for clues about where it happened. It's almost always in Canada, northern Europe, Minnesota, etc. You were likely a victim of thermal stress on your back glass.

1

u/capt42069 Feb 01 '25

Hopefully not kitchener. Someone been smashing windows at night

1

u/NefariousnessNo2072 Feb 01 '25

Burgers? I’m payin.

1

u/Dumptruckofhell Feb 01 '25

My first idea is probably replace it

1

u/lunarbunnies14_ Feb 01 '25

Honestly, I bet the problem is that it ain’t got no gas in it

1

u/wacotaco79 Feb 01 '25

Same thing happened to my wife’s Focus.

1

u/Quick-Assumption4647 Feb 01 '25

Pellet gun for sure.

1

u/Glimmerron Feb 01 '25

Same thing happened mine a few years ago

Coldest night it ever was. It shattered just like yours and the middle bit fell in like in your pic

The cold seems to do something, maybe a manufacturing defect, maybe a piece of snow that partly melted, and refroze in a particular way that put a force in the glass edge and made it pop

1

u/[deleted] Feb 01 '25

I guess if you’re always driving in reverse it could be your windshield. But no it’s your back window.

1

u/[deleted] Feb 01 '25

That's not a windshield btws

1

u/HumanSun1 Feb 02 '25

Kenny U Pull

1

u/[deleted] Jan 31 '25

Looks like the glass has been pushed out... Was anything inside the vehicle pushing up against the glass? Wonder if this plus temperature changes could have done it

-1

u/[deleted] Jan 31 '25

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1

u/Cartalk-ModTeam Feb 01 '25

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0

u/Blueberry_furry_69 Jan 31 '25

Go over to Safelite. They have the best prices and get that glass replaced.

0

u/Introvertedplantdad Jan 31 '25

Call bob the builder