BigBlast

Guess there is a first time for everything.. Sitting still, warming up the jeep on a cool day (mid 40's), in the garage. I was sitting in the driver seat checking my phone, with the windshield defroster on (not even high), for a couple of minutes when - POP! I did not see it at first, due to inspection sticker, but the windshield popped a crack from the bottom center about 4 inches up and arcing toward the driver side. WTF? - from the moderately warm air from the defroster? Couldn't happen, but I did a close inspection of the windshield - no nick from strikes etc. and it clearly starts from the bottom of the windshield - clean even crack..
Still have 2+ years and more than enough miles left on the warranty for my 2013, and am going to peruse with dealer - learned a lot about glass and heat with a fireplace shatter recently, hoping to use some of those arguments - but if anyone has any good "facts" that may help me, they would be greatly appreciated..

Pylot7

I was driving from Greeley back to Denver on a December day at minus 19 degrees. Had my defroster going and POP had the exact same thing happen to me. Up about four inches from the bottom of the glass then took a left turn.

What will happen at the dealer is this, they will feel the crack and find the grain of sand size chip in it and blame it on a chip.

No new windshield for you!!

Here in Colorado I have never had a windshield go without a crack for more than 6 months. There is so much gravel and the oil field trucks have so much mud on them that rock chips are inevitable.

gmag16

Just replaced mine yesterday. Tuesday, the temps went from 60 degrees and raining (defrosters were being used) to 34 degrees and sleeting, and the temps dropped ridiculously fast. Needless to say i didn't hear the pop noise (over the radio and highway wind noise) but noticed when i made a stop but by then, it was getting too dark to inspect the windshield. When i did inspect the following morning, i did notice a tiny rock chip just about the wiper blade. =(

Sent using the Force

airforce26yrs

Mine did the same thing this year. Right in front of the driver running up about 4 inches and then left turn to frame. Thank God for no co pay insurance.

ronjenx

If it's truly not from a rock strike, it could be from some torsional pressure from the windshield frame, and uneven heating from the defroster was the last straw.

I've never had it happen and I've applied the defroster when it was -30°F.

BigBlast

I learned a lot about the tempering process from replacing a shattered fireplace glass this winter - crazy, same thing (sort of) walked down in the morning flipped on the gas fireplace and BOOM! I swear I jumped 10 feet that damn thing was so loud. Anyhow, I have a friend who replaced it, and he explained a great deal about the process, and industry known weaknesses in the "assembly line" tempering due to the speed of the lines..
However, this is a good point as well, as I have noticed some misalignment in the Freedom Panels - even brought it in to the same deal previously.. So at least now I have two arguing points..
I have looked at it extremely closely and there are 0 chips on the windshield - let alone near/around/on the crack..

Mr Big Bear

that happened on my wife's patriot too. exactly what you said the dealer would say, they said!

Jeepstin12

Happened to mine as well. Rocks kicking up are one thing, but the defrost doing it??? The only thing I can conclude is how little surface area there is on a jeep windshield and not much room for expansion. My land rover took rock hits all the time. 5 windshields in that thing over the course if 6 years. And they were the nice $1400 windshield with the heated element. Yeah, Allstate loved that one.

tspevacek

I have a 97 Ranger. I had the windshield replaced in 99 at a shop because of a rock chip that cracked the glass. I was on my way home happy with a new windshield I was behind a logging truck. ( was stationed at Ft Polk) and heard a rock that sounded like it tap danced down my hood and smacked my windshield and cracked it. I could not believe I had a windshield in my vehicle for less then 1 hour and it needed replaced again. I know it is not related to the topic but it is funny now that I look back at it but I was beyond pissed the day it happened,

btadlock

I did experience the same on my 97 TJ, cold weather, running the defroster and "POP", crack from the rearview mirror mount to the bottom.
I was told by the guy that replaced mine, that a defect free windshield "should" not do that, but if you had a chip or small crack, the heat would exploit it for sure.