paulmj1

The WSJ has an article that with the impending shortage of Russian gas in Europe, car companies are stockpiling glass windshields, which is energy intensive manufacturing process. Since we’ve already replaced our GLE windshield twice due to rock damage, I was wondering if it would impact a USA-built Mercedes?

chassis

Either Asahi, Fuyao or Pilkington. All have major factories in the U.S.

More importantly than windshields where multiple alternative sources exist, is engine and transmission production which is Germany-only for many models. Especially natural gas intensive casting and forging operations for engine blocks, crankshafts, cylinder heads, connecting rods, etc.

The German government could be deciding whether to allocate natural gas to heat grandma’s house or to allow MB to build another 4.0L TT V8 for an AMG.

mikapen

As @chassis said, there are many OEM and additional aftermarket suppliers.
There is always a limited supply when new model is introduced, because it takes a while for the aftermarkets to tool up for the new shapes, RF and IR requirements, so they will probably be the first to go short.
I'm on my third windshield. Drat. My main road to the big city is a 40 mile two lane, with many convoys of gravel trucks, leaving their trails behind.
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Ron.s

My limited experience is that the Acoustic Comfort Windshield is more fragile than others. The sandwich in between the glass seems to result in hits that aren’t round and not repairable. My last replacement must be a little different than previous since no more windshield wiper sticking.
Anyone else notice these two…
Edit-Many major suppliers are located on Mercedes Vance Campus or very close.

mikapen

I also suspect my acoustic windshield is less impact resistant than plain old laminated glass.
I've always insisted on Mercedes OEM glass, from the dealer. And I've been surprised at how some rocks have just bounced off, leaving a mere chip.

I know flying rocks have unpredictable impacts, and all those trajectories, spins and speed are happenstance.
But it seems I have taken bigger hits with other Mercedes cars with minor damage.

​​​​​​So I also wonder about the strength of the acoustic glass.

paulmj1

Several months ago we were crossing the Colorado River on the bridge facing Glen Canyon Dam and Lake Powell. We were the only vehicle on the bridge in either direction when there was a loud crack and a dime-sized hole appeared on the windshield. Since then, I assumed it was a bullet falling out of the sky, shot by a celebrant somewhere nearby.

TonyF61

Cracked mine within two weeks of delivery. Been driving 70 miles a day on the same stretch of highway for 30 years. Get hit with stones all the time. Only one other "ding" on an X5. I too believe the MB windshield is more fragile. In addition, instead of a "circle" or bullseye, the windshield just cracked - odd. On the plus side, it was half the price what BMW charged.

mikapen

Actually, the first MB windshield that I didn't think was "bombproof" was the Acoustic Glass.
I've taken some amazing hits, several sounded like gunshots, with almost imperceptible damage. That's why I've always insisted on OE glass instead of the insurance company's contracted source. At the Dealer (who often subcontracts, but then they are in charge of accepting the glass/installation/calibration). (It'sd usually a hundred or four under the insurance company's Contracted Supplier.)
Even passengers have remarked at some of the hits we've had with little of no damage.

So I still feel more confident with MB glass than other recent manufacturers I've had.
But since stone hits are so random and unpredictable, the best glass in the world could be taken out weekly, with the wrong luck!
So I can't pin it on the Acoustic Glass because of the randomness.

I'm heading to the Big City and will face the 100 mile gravel truck convoys once again. They tend to go 5 under in 12 truck groups. Maybe I should take the GLC. Naw - I'll take my chances.

TonyF61

A buddy of mine had the windshield on his a 2019 G550 Brabus crack two weeks before a car show that it was entered in. The day he picked it up from MB with the replacement windshield, he was driving down to Atlantic City to the car show, and the windshield cracked, again. May have been defective product or something wrong with the installation, but cracked nonetheless.

Neurobit

Different experience with the acoustic glass for me. I've gotten hit several times, three times coming back from a recent trip which were big hits, and all it did was pin size damage to the glass but no major chips or cracks
This happened while raining and I was certain that when the glass would dry I would see major damage. Pleasantly surprised at how tough this windshield is.

Cheers,

Ron.s

I had much the same experience twice and after some hot and cold on the windshield it started cracking. Oddly, very little straight line on the cracks. One was S shaped and the other like a poorly drawn half circle…repaired sooner so it wasn’t done yet. Once it took about 3 months for the crack to begin spreading. It was about 3-4” from the top. I noticed it in April washing the car (could catch my fingernail) but it was July before it took off.
Both times the crack started from a tiny hit…both with “kind of” a vertical crack with no divot to repair. Let’s hope my experience isn’t typical!
My first GLE didn’t have the Acoustic Windshield and over 2 winters had 3 different 1/4” hits repaired. It had terrible rock rash and would have been nice if it had cracked. It’s not a bad deal to get a pitted windshield replaced with a new one for $100.

chassis

It's cost reduction.

Carmakers use thinner (while also stronger) glass to save money and weight (emissions, fuel economy).

All else being equal, windshield (thin membrane-like structure) strength is proportional to the second (square) or third power of thickness. I don't have my handbook nearby so let's say thickness has a "real big" effect on strength. Thickness effects overpower any improvement glass strength by virtue of its chemical composition or alloy.

Carmakers cheap out on windshields. Consumers deal with the inconvenience. This is not an MB-only phenomenon, other brands including BMW exhibit the same phenomenon.

mikapen

I agree that light weight is a primary factor in all components.

I don't think they are cheaping out on glass, though. It has become a structural element, and there are plenty of IIHS and NHTSA crash and rollover tests that need to be satisfied. Saving $100 and failing a rollover test would be hard to justify, even for the Bean counters.

I also don't agree with your math application, because there are a lot more things such as ductility brittleness tensile strength compressive strength flexibility surface hardening and so forth, that goes into glass and it's strength, under different stresses.
It's like comparing steel to high strength steel, to carbon fiber, and saying that thickness affects strength. The actual materials usually have a bigger effect.

All our tales of cracked windshields are anecdotal, because no impact or stress is the same.

We don't even know what, exactly. constitutes acoustic glass. Is it a different laminate, or just the film on the inside surface? Is the glass any different from a standard windshield?
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I'm suspicious that my acoustic class is weaker because I've had to replace two and need it again.

But I have to report that my 100 mile round trip today, in our gravel truck convoys, had three major attacks from trucks. One was like someone threw out a large shovel full of rocks just one car ahead and a lot of them hit my windshield hard. Two other episodes in a construction zone or oncoming traffic picked up rocks and cars in front were swerving. I almost missed it but didn't. Quite a bit more little chips but no bullseyes or cracks.
So today I was proud of my acoustic glass. And my PPF.

chassis

Agree that windshields have a structural role to play. Agree that carmakers need to meet all regulations. No one has suggested otherwise. It's a red herring argument.

Thickness plays a dominant role in yielding of thin structures. As I mentioned I don't have my handy-dandy references nearby. I am traveling for a while so I won't be digging for it soon. Maybe you can look it up.

Carmakers, including and especially MB, are cheaping out on windshields. Dealers outsource windshield replacement labor to third parties. Insurance companies outsource glass claims to third parties. The consumer is left standing there, looking around.

jaxslk

Holy war zone, batman.

You need a beater car to commute with and leave the Merc safely home in the garage. I'd lose my sanity getting pelted like you described on a fairly regular basis. Oy.

mikapen

Ain't no handbook going to analyze my windshield. If you have Mercedes engineering specs then I can read them.
Do you know where to find the glass chemistry, assembly and curing process,

I think we're just wondering what kind of glass it is.

mikapen

Yeah, no kidding!. I'd have a beater for that trip if it were a commute but it's only something I do a few times a month, to the big city for Big City stuff.

I just got some curb rash on my left front wheel last weekend, so I guess I have taken it out of the pristine category anyway. it's a great, twisty Drive between convoys.

mikapen

The thickness of the windshield is specified. It meets the engineering standards for crashworthiness and occupant protection.
All the trim pieces and moldings are sized to that specified thickness, and the spacers for installation are also as specified for that glass thickness.

We are not talking about the yield strength of glass. We are talking about integrity from all sorts of forces and stresses. I listed several of them above and there are quite a few more. I'm betting that your handbook doesn't have all of those engineering specs for a 167 windshield.

Aside for my recent tribulations with this car (which corresponded to the neighboring County shutting down gravel mining and forcing all their gravel to come from our County!), I've always thought Mercedes windshields were the best I've had.
And it certainly isn't cheap.

You don't have to take third-party glass. You don't have to take what the insurance company says. That's the law. You only have to look around as far as your dealer.
BTW my last five MB windshields we're done at the dealer, and it saved enough money to pay my deductible. Ie cheaper than the insurance contractor. Better glass, too.

chassis

My handbook is what the MB engineers used to come up with the windshield design. It's the Engineering 101 handbook. Agree on forces and stresses, again back to Engineering 101. There is nothing magic at all about any MB, or more specifically any 167.

nextmilenium

Since we are talking about the windshield, does anyone carry windshield replacement coverage on their auto insurance? I looked into adding this coverage and it would cost me about $350 additional per year.
Debating if this is worth it. I've gotten couple of rock chips and I'm worried I won't be so lucky next time.

I used Safelite website to get a quote on replacing my windshield and it varied depending on the options you have. I only have HUD and it came out to be about $2600 and I'm not sure if that is OEM or not.

Neurobit

I have this through Progressive. I believe it's an additional $70 every six months w/ zero deductible (four vehicles).

Cheers,

nextmilenium

Wow, that is a very reasonable amount. I have AAA and they want $350 per year for just the GLE.

Ron.s

Is there a difference between Comprehensive with a $100 deductible and specific windshield coverage? Comprehensive covers other hazards in addition to the windshield.
From a search “Comprehensive coverage helps pay to repair or replace your car if it's stolen or damaged by something other than a collision. Comprehensive typically helps cover theft and damage from vandalism and natural disasters, falling objects, fire, hail, flood or animals.“
My Comp is $328 a year and I just had my windshield replaced with OEM for $100 deductible. I think most policies will up charge over the deductible for an OEM windshields if a generic is available.

nextmilenium

My bad. I misunderstood the "Full Safety Glass" coverage in my auto policy as something I would need if I wanted to get my windshield replaced.
It turns out "Full Safety Glass" coverage just means it would waive the comprehensive deductible in case the windshield or any glasses needed replacement.
Since it would add about $300 per year to my policy, I don't think it's worth it. If anything, I can lower my $500 comprehensive deductible to $100 and my annual premium only increases by $100.

Jzegel

I have Amica w/ full glass coverage on both GLE's, costs about $147/ 6 mo for both. Any glass broken means no deductible and no impact on future insurance rates if you use it.

I used Safelite quite few times until they came out to my driveway with Chinese glass that was cracked OOTB, 2nd one didn't even fit properly. Used the local MB dealer, paid out of pocket for OEM glass for a ($1.8K!) replacement and got reimbursed the next week.