Rear Window Shattered Spontaneously While Driving on Highway

[rpm5099]

I have a 2007 4Runner with 106k miles on it. I was driving to work today on the highway going about 65mph when all of a sudden my rear window shattered, or really exploded, for absolutely no reason. There were no vehicles within ~50 yards behind me in the same lane or the lane to the right. It was overcast about 85 degrees, the defroster was not on and I was not raising or lowering the glass at the time. There was nothing in the back of the vehicle at all, in fact I had recently vacuumed it.

I have heard every explanation under the sun, most of them blaming the defroster which clearly was not on because it was a sunny day in July. The defect in the glass argument doesn't hold much water given the car is 7 years old and has 106k miles on it. The road on that stretch was smooth with no bumps. I was in the left lane with a large open grass median that no one was on, and there was no lawn mowing or anything going on. No jackass could have been hiding with a pellet gun, and I was not near an overpass. I am totally at a loss to explain this. Safelite is going to fix it tomorrow for $425. Has anyone ever heard of this happening with truly no cause at all?!

 

[Chewbacca]

It has happened to me but not with automotive glass. I have had my shower glass doors explode out of no where and when I had a guy install some new ones he said it's very common that a previous hit or something will cause a small crack. Over time a vibration, movement, or even car bass can cause the crack to rapidly expand and shatter the glass.


I was taking a dump when it decided to explode. Scary shit literally. lol

 

[2014 Warthog]

Did you have any other windows/sunroof open in the car?

It's somewhat common to have the sunroof explode if you have like the 2nd row windows open and you get that pulsing "whopwhopwhop" air effect going... Not personally heard of it taking the back out but I could see that happening too.

 

[rpm5099]

I know what you are talking about but there was none of that kind of buffeting going on. I had both front windows most of the way open. Regardless a tempered glass rear window should be able to take enough buffeting of wind far past when your eardrums exploded.

Did you have any other windows/sunroof open in the car?

It's somewhat common to have the sunroof explode if you have like the 2nd row windows open and you get that pulsing "whopwhopwhop" air effect going... Not personally heard of it taking the back out but I could see that happening too.

 

[scottp999]

Thanks for this thread. This happened to my wife yesterday. 2006 4runner sr5 with 105k miles. Also thanking this thread, as the rear lift gate lock was not working until I disconnected (for 45 sec) and reconnected the negative battery terminal:

http://www.toyota-4runner.org/4th-gen-t4rs/80823-diy-lift-gate-lock-assembly-4.html

 

[JPL]

Mine rear glass just exploded @ 10mph on a smooth road, yesterday out of nowhere, I guess the only thing that was out of the norm is that I had the heater on, rear defrost on and it was ice fog outside....thought I got shot....

 

[mag4x4]

Better make sure your wife didn't raise your life insurance policy.

 

[JPL]

It was a short right where the wires connect to the rear window, must have got real hot and popped.

 

[07 runner]

Wow this is crazy. I really hope this doesn't happen to mine some day

 

[rpm5099]

Real late response - I don't think I have any life insurance, haha. I think I had the front windows rolled down, which I know creates a vacuum because I've noticed that whenever you start moving with the back glass down it just sucks exhaust in - I am sure it exerts some force inwards on the rear glass, but it would have to be severely compromised to break just from that. At first I thought I had hit an IED on MD 295! Still no idea what happened, just one of those things I guess.

 

[TxCowgirlInCo]

I completely know what you mean! We were driving in freezing weather the other night with one a snowplow way in front of us and a truck a good distance behind us when suddenly there was an explosion sound and broken glass everywhere. Both of us ducked on instinct as if we’d been shot at. It really is terrifying! There doesn’t seem to be a full recall on it outside of warranty however the fact that they only posted the service bulletin about it in 2017 and it applies to 06-09 we’re all out of warranty. I read a few places that if call the dealer and harass them, they will sometimes do it at no cost. I’m gonna try bugging them tomorrow to see if they’ll do mine.

 

[Wild Thing]

Had this happen to an '85 Bronco while living in Wyoming. Parked it behind a building to load some gear for field work. Got the gear from my office and was leaning it against the building by the rig when I heard a loud crash. Turned around to find the whole rear window in pieces on the ground, with pieces rattling 'round in the rear door. Turned out that the window bracket and lift mechanism were so rusted that it finally gave way - perfect timing for a winter work outing. Wound up selling it soon thereafter.

 

[ran]

Before my Toyota days I had a early 80's Firebird. My buddy bought one also, a bit newer. He went thru 3 back windows and sold it. they never figured it out.
__________________
2007 SE V6 titanium 265-70-17 Cooper AT3 4S

 

[baby#yota]

That’s a wild thing to have happen, I’ve often wondered how much strain I’m putting on my rear window when it’s half open and driving. Automotive class shouldn’t “explode” like that, which is odd, the resin laminate between the panes is supposed to stop that from happening. Very odd, if it was a kid with a pellet gun that’s an impressive shot but highly unlikely.

 

[AuSeeker]

That’s a wild thing to have happen, I’ve often wondered how much strain I’m putting on my rear window when it’s half open and driving. Automotive class shouldn’t “explode” like that, which is odd, the resin laminate between the panes is supposed to stop that from happening. Very odd, if it was a kid with a pellet gun that’s an impressive shot but highly unlikely.

The most common cause of this happening in 4th GENS T4Rs is the rear glass defroster connection overheating, but it could also happen from a tiny scratch expanding further.

Here's a recent topic sorta discussing the defroster issue.

how to disable rear defrost

Also just an FYI...in most if not all vehicles the only glass that is tempered AND also laminated is the windshield, all other glass is just tempered and will shatter into 1000s of pieces, the windshield is laminate to prevent injury of the glass hitting you in the face, etc..

 

[baby#yota]

The most common cause of this happening in 4th GENS T4Rs is the rear glass defroster connection overheating, but it could also happen from a tiny scratch expanding further.

Here's a recent topic sorta discussing the defroster issue.

how to disable rear defrost

Also just an FYI...in most if not all vehicles the only glass that is tempered AND also laminated is the windshield, all other glass is just tempered and will shatter into 1000s of pieces, the windshield is laminate to prevent injury of the glass hitting you in the face, etc..

hmm, thanks for the info. I was under the assumption that even the windows were laminate glass as well. hope I never find out

 

[AuSeeker]

hmm, thanks for the info. I was under the assumption that even the windows were laminate glass as well. hope I never find out

Actually in early auto safety glass all the windows were laminated glass...BUT not tempered, regular glass breaks into many large "daggers/knife" like pieces that would cut and many times kill people in auto accidents, so they started laminating auto glass to keep it all together when it breaks instead of the many knifes, once they developed tempered glass the danger was gone so only the windshield is laminated now to stop the little pieces from blinding people in accidents and also it sorta helps keeping body parts within the vehicle in an accident.