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Exploding sunroofs

Consumer Reports just posted an article about it online today.

I had an “exploding” passenger side door window on my 2007 Chrysler Town and Country a few summers back. Disintegrated at highway speed with no discernable cause.

I’m curious, what was the ambient temperature? Had the vehicle been parked in the sun a long time?
These sound like thermal stress failures. Up here in NH I’ve never heard of this happening. I’m wondering of extreme heat is a factor.

I had been driving west and north in Wisconsin for several hours on a summer day, temps probably high 70s to low 80s F. The window was closed and just crumbled instantaneously with a roar of wind and the sound of glass crumbles washing against the side of the van. I called 911 and a police officer and I looked for any sign of foul play - had someone shot at the vehicle? - but it remains a mystery. I made my way back to a glass shop in Ashland, holding onto the cat. They could not fix it yet that day but they taped plastic in place and I made it back home to Duluth and got it fixed the next day.

Nobody had an explanation, but the officer and the glass man (a former student of mine) had seen or heard of that kind of thing. Fortunately my wife was not along on this trip. She would have been right there in the front passenger seat, inches away from the rush of glass and wind.

Just one more reason to avoid sunroofs. But they’re almost mandatory on many new vehicles these days.

I’ve had 5 vehicles with sunroofs. Never had one shatter. I think the statistical likelihood that your sunroof will explode is probably somewhere between winning the lottery and getting eaten by a shark. Less than 900 complaints since 1995? Between 17 and 18 million cars get sold every year. Even if only 1/8th of them had sunroofs, that’s still around 2 million cars a year with sunroofs. 900 really isn’t a big number at all in that group.

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+1
I have had 4 vehicles with glass sunroofs over a period of 25 years, and none of them shattered, leaked, or malfunctioned in any way. No, I did not actually want those sunroofs, but in order to get certain options that I wanted, I had to accept the reality that those options came only in “packages” that included the sunroofs. I will admit that I occasionally open mine on a hot day in order to air out the car for the first couple of minutes of driving, but for the most part they stay closed–and totally secure.

Please note that I am not trying to ascribe any kind of blame to people whose sunroofs explode, but–as shadowfax implied–these events are statistically insignificant.

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My main problem is that I don’t fit in many cars with sunroofs because of the headroom they take away.

An ordinary drinking glass sitting on a shelf can suddenly explode (shatter).

Re sunroofs, I’ve never had one shatter, and I’ve owned 3. And never used any of them. Forced to buy them (as part of package).

My 2006 Accord’s moonroof glass shattered when the car was 2 years old. I was driving in steady state conditions on the highway. No bumps, no sudden temp changes. Dry conditions. It went “POP!” The glass then fell on my head and down my face and lap. Most of the pieces were small cubes about a quarter inch on a side, but there was a lot of glass “dust” and smaller parts too. I exited and went to the nearest gas station with a vac. I vacuumed the glass off my head first and then - stupidly - my eyebrows. I got away with it, but I could easily have sucked out an eyeball. I then sucked up all the glass inside the car and in the roof crevices. Scared me big time. Insurance paid the cost. In my state, all glass is covered with no deductable. As a result of this, I only open the sun shade on vehicles when I actually want the sun. Otherwise, I always keep it shut. Glass in your eyes is no picnic.Honda Moonroof Glas Broken 11-23-10

I am only on my second sunroof my 1990 Mazda RX7 which was steel and my 2010 Kia Forte SX is glass. I also only use it briefly to exhaust hot air so most of the time it is closed with the shade also closed.

Tempered glass has residual stresses in it. A small crack inside or a small crack on the surface from a rock will not necessarily make the glass fail immediately. The crack can grow and reach a critical crack length, and that is when the catastrophic failure occurs. I had this happen with a tempered glass shower door about 30 years ago. I heard a loud noise and discovered a pile of glass pebbles on the floor below where the door used to be.

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I think jtsanders is exactly right. These pre-stressed panels get a minor score or divot and then they pop when the conditions are just right. What I don’t get is why these parts don’t have a simple elastomeric film, like that in windshields, so that if they do go, the stuff doesn’t fall directly in the face of the driver.

I think it’s cost. The likelihood of taking a rock strike on the roof is much lower than on the windshield. If the plastic coating is on the outside, it will fog over time due to UV damage.

I also had a shower door do the same thing about 30 year’s ago I did not hear it but my daughter was in the shower at the time & I did hear her scream ran in & found her standing in a pile of glass.

The reason tempered glass is used in sunroofs and side windows is that if it fails it turns into thousands of small, relatively nondangerous pieces rather than large shards sharp enough to cut a head off. Or slice a jugular.

Laminated glass is used in the windshield to prevent the glass from blowing into the driver’s face. IMHO laminated glass should be required for all auto glass, but they never asked me my opinion when they set the standards. :grin:

We just got a new car with a sunroof First one ever for me, if I get to drive it, the likelihood of a problem seems small, But stuff happens, just hope it does not happen to us.

My EX-L Accord comes with the sunroof as part of the trim level. I haven’t had a broken sunroof yet, but it could happen, especially if I followed dump trucks with faulty load covers. I always keep the sun screen under the sunroof closed, and the glass would just collect there anyway. The article said that there are more problems with the panoramic sunroofs. Those are more likely on expensive cars and SUVs. I try to move from behind dump trucks anyway. Dried mud falls off the undercarriage and there are always rocks in the mud it seems.

The only way my Scion tC came was with a sunroof. I’d never had one before, and it had no influence whatsoever in my purchasing decision, but I love it. I like lots of fresh air. The only time I’ve ever turned my AC on is at the request of a passenger.

However, as much as I like my sunroof, there are other factors that will take precedence should I buy another car. Comfort is numero uno priority. Good tracking on the highway is another. Reliability and affordability are others. If the vehicle that passes all these tests has a sunroof, that’ll be great. If not, that’ll be okay.

Wow 859 complaints since 1995. Considering how many millions of cars that have been made with glass sun/moon roofs since then, even if the number of complaints were 10 times that it still wouldn’t be news, Sorry folks but with everything else going on in the world today, a product with such a minuscule failure rate is not news worthy.

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