Strengthen Windshield Against Rock Chips?

Is there any way to reduce rock chips of the windshield? I'm losing the battle against tiny rock chips in my windshield. They're not very big and hardly noticeable from the exterior, but I notice them from the drivers seat when the sun hits them at the right direction. They're mostly obtained at high highways speeds by the car in front kicking up tiny pebbles from their spinning wheels.

I know there's nothing I can do for the current chips, but is there a liquid or coating I can put on the outside of my windshield glass that will strengthen it? I often hear that ceramic coatings increase the "hardness" considerably, but don't know if there are any specifically made for windshields? I wouldn't want to get any haziness or cloudiness. I heard some people put PPF on their windshields, but I'd rather not go that far.

Nothing applied to the glass is going to "strengthen" it to resist chips - increase your following distance! Adam's has a ceramic glass coating that helps resist scratches & keeps it clean.
https://adamspolishes.com/products/graphene-ceramic-glass-coating

There are windshield protective films. XPEL, Windshield Skin, Diamond Shield.
https://www.xpel.com/products/windshield-protection-film

JoeyO wrote

Is there any way to reduce rock chips of the windshield?

Stop tailgating

Ceramic coatings are a magic potion that won’t do ANYTHING to prevent rock chips

MJBO wrote

JoeyO wrote

Is there any way to reduce rock chips of the windshield?

Stop tailgating

Ceramic coatings are a magic potion that won’t do ANYTHING to prevent rock chips

That was so funny I forgot to laugh.

And I do try not to tailgate. But I’ve received a few pebbles from passing cars in the passing lane.

Unfortunately there’s not much that can be done outside of PPF. Coatings are extremely thin. That’s like trying to protect against a bullet with a piece of plywood.

Around here I get pummeled by the dump trucks on the highway. They’re brutal. I can’t go anywhere without dodging rocks that are flying off dump trucks. My driving style involves identifying where the “tick tick” sound is originating from and getting in front of it to stop the damage.

If you want to keep your car nice, don’t drive it anywhere. Haha.

On my Cayman, I'm on my second windshield PPF. ClearPlex was the first, and now ExoShield. Xpel recently came out with their windshield film too, I'll probably try that next because my trusted PPF installer now does those. For a street driven car, plan to replace it every 10K miles if you get one, because the film ends up getting scratched when the windshield wipers are used if there's dust or dirt on the windshield. But so far, I'm happy with both of mine. There's quite a bit of optical distortion the first few weeks after the installation, but it does clear up on its own.

My g80 is 6 months old and I’m on my second windshield. The rock and chip it caused missed 3 cars in front of me and somehow broke into my windshield. I thought “well, that’s not a horrible chip and I can live with it for a while”, and then the crack appeared and raced from left A pillar to the middle of the windshield.

I guess I’m fortunate as it was 2mm away from the A pillar and would have done some paint damage. Do guys PPF their windshields? I’ve got a full front cap PPF job and have been really happy with it, but didn’t even ask about doing the windshield.

Henn28 wrote

My g80 is 6 months old and I’m on my second windshield. The rock and chip it caused missed 3 cars in front of me and somehow broke into my windshield. I thought “well, that’s not a horrible chip and I can live with it for a while”, and then the crack appeared and raced from left A pillar to the middle of the windshield.

I guess I’m fortunate as it was 2mm away from the A pillar and would have done some paint damage. Do guys PPF their windshields? I’ve got a full front cap PPF job and have been really happy with it, but didn’t even ask about doing the windshield.

Windshield PPF is not recommended unless it's a car that is RARELY driven. It's also not cheap.. in my area to do a front windshield it's ~700 dollars and you probably would need to replace it yearly if not earlier if it's daily driven and wipers are used on it. That's why there is only a 1 year warranty on windshield PPF compared to 10 or 12 year on normal paint PPF.

You probably need to weigh the costs of doing a Windshield PPF yearly compared to replacing front windshields costs... 2 in 6 months seems like pretty bad luck lol.

N1rve wrote

Windshield PPF is not recommended unless it's a car that is RARELY driven. It's also not cheap.. in my area to do a front windshield it's ~700 dollars and you probably would need to replace it yearly if not earlier if it's daily driven and wipers are used on it. That's why there is only a 1 year warranty on windshield PPF compared to 10 or 12 year on normal paint PPF.

You probably need to weigh the costs of doing a Windshield PPF yearly compared to replacing front windshields costs... 2 in 6 months seems like pretty bad luck lol.

Thanks for the info. That math probably doesn’t work out then as a new OE windshield from BMW was about $1600. I’ve had decent luck with safelite on other cars, but figured with the calibration that needed to be done on the G80 taking it to the dealership was the way to go. Safelite quote was around $900, but I’m not sure if that was OE glass.

Funny that people jump straight to "stop tailgating" for chips when it's one of many reasons people get them. About 75% of the windshield chips/dings I've gotten on my Trucks, Motorcycles/Helmets, and cars have come from either oncoming traffic or cars in other lanes... its happened on the freeway in the fast lane, on undivided roads/highways (particularly highway 12), and in the slow lane, with no one in front of me, by cars to my left.

A few times, I've even seen them coming - a rock/pebble, screw, nut, etc will get kicked up by an oncoming car, or to my left/right, and I see it coming at the last second, unable to process it before I hear the impact. So, yea, most of one's I've immediately noticed didn't come from the car directly in front of me.

When I added my M340 to my insurance in April, I looked into adding windshield coverage for it and it was $1000/yr. Curious, I looked at what it would cost to add it to my Ram 1500 truck ($100) or my wife's Venza ($94). The disparity didn't seem right and called and to ask my insurer about the huge difference... according to the rep, BMW and Subaru are tied for the most overall cost to add windshield coverage... by a wide margin. They said it was largely due to the incidence rate + replacement costs, thanks to BMW's HUDs/Cameras & Subaru's EyeSight Driver Assist. Since I maintain a $1k deductible on my comprehensive and windshield chips are covered but don't count against premium increases, I figured it's better to just use that, as needed, rather than paying it every year regardless of damage.

I'd considered one of the options PPFing my windshield (fine until you need your wipers) or gorilla glass (no protectors, only full windshields that aren't much better than regular glass). Unfortunately, nothing currently on the market will provide a better ROI+daily-driver-experience than just replacing as necessary (yes, and minimizing tailgating)

I suppose my point is; tailgating is one of many sources of issues. But, given the highly chip-prone windows, often $2k+ cost of replacement (particularly on cars with HUDs or driver assist cameras), and high cost of dedicated coverage, it makes a lot of sense why people are looking to protect themselves from the relatively extreme costs of windshield damage.

I basically daily my 2021 M4, which has 123,000 miles. And I have the windshield PPF, and have only needed to replace it twice. And I've been on road rallies, and such.

Having said that, I don't drive it much in the rain, so the wipers aren't used often. Lots of wiper use will certainly leave "wipe marks" on the PPF, as any leaves, pebbles, and dirt trapped between the wipers and the windshield could leave a mark on the PPF. Once these accrue, you'll have to replace it...though some of these marks will self-heal over time, especially in warm weather. But most don't have the patience, like me, so once severely scratched, we replace. Having a good windshield treatment will help reduce the need to even use the wipers, as once you get above about 35 mph, the rain drops will just slide off the windshield with no need for the wipers. So if I know I'll have to drive in the rain, I'll treat the windshield beforehand, and right now I'm using Stek's Cure19, which is decent. I haven't found an outstanding one yet. https://parkscarcare.net/products/stek-formula-19-cure-500ml-hydrophobic-film-aftercare-solution?srsltid=AfmBOopA5grrXxbzcXmf5Z9pvpbXY3eHXNVFM64s3CvxcvmzSfEf2Pw4

I'll also add, I'm not a tailgater, I leave a lot of space...especially during high-speed driving. And I avoid ALL trucks, especially dump and cement trucks. I try to never be behind them, even 10+ car links back...plus when I do pass them, I will try to pass from the farthest away lane. I cringe when I know we're approaching a rough patch of road and I'm anywhere behind a cement or dump truck...because you know some rocks or dirt are going to be released from the rear of these trucks.

Last, I've always had some initial "waviness" when the new front PPF is installed. But it gradually goes away over time, though it may take a while...and it goes away faster in warmer, summer temperatures than wintertime. The heat emanating from the engine bay in some cars (like smaller-engine turbo cars) will also contribute to the PPF waviness fading away on the windshield.

JoeyO wrote

And I do try not to tailgate. But I’ve received a few pebbles from passing cars in the passing lane.

Sure you can - speed up so that people don't pass you so often!

And no, there is not much you can do, beyond lowering your glass deductible. BMW OEM glass is notoriously soft.

John in VA wrote

Adam's has a ceramic glass coating that helps resist scratches & keeps it clean.

It doesn't, and it doesn't.
Ceramic coatings are a good idea (for visibility in the rain), but they do NOTHING to protect glass against scratches or rock chips. They also do nothing to kind windshield "clean".

While beading water off glass at high speed works great (which is why I have ceramic on all my cars), promoting beeding while the car is parked creates water spots galore. Which is the opposite of clean.

N1rve wrote

Windshield PPF is not recommended unless it's a car that is RARELY driven. It's also not cheap.. in my area to do a front windshield it's ~700 dollars and you probably would need to replace it yearly if not earlier if it's daily driven and wipers are used on it.

Yep.
PPF condoms are expensive, and PPF-ing glass is just about the least appropriate application imaginable. For many reasons, including financial one.

Henn28 wrote

I’ve had decent luck with safelite on other cars, but figured with the calibration that needed to be done on the G80 taking it to the dealership was the way to go.

So-called "calibration" (otherwise known as wall-job) is brain dead simple, and all glass installers can do it. Including Safelite. BTDT.

Henn28 wrote

Safelite quote was around $900, but I’m not sure if that was OE glass.

You can always ask.
Safelite will often cary multiple glass options, but they quote the cheapest one to get you in the door.

HTH,
a

The first windshield on my 2018 M5 lasted 55k miles. Then 2 Safelite non BMW windshields in 5k miles. Had Safelite put in a BMW windshield after the 2nd non BMW failure and it has been in there 15k miles so far. Count all be luck or coincidence. My driving conditions have not changed.

^Dang, that's crazy

When I drive my beater cars I do not get chips etc. but when I take the garage queens out they get pummeled. The nicer and more valuable the car is, the less likely you end up driving it.

Machinebuilder wrote

The nicer and more valuable the car is, the less likely you end up driving it.

YMMV.

I put over 10000km on my 2014 Vanquish in less than six months. 30000km on my first M3T in less than two years.

MJBO wrote

JoeyO wrote

Is there any way to reduce rock chips of the windshield?

Stop tailgating

Ceramic coatings are a magic potion that won’t do ANYTHING to prevent rock chips

Interstate driving is bad. You have to go out of your way to space off and not follow trucks or even cars.

I had to replace the windshield on the M340i in the first year. I was on a highway in Colorado and a muddy pickup pulling a horse trailer cut in front of me as I slowed to let him in. Bad decision. My insurance pays for OEM glass the first year.

MJBO wrote

Machinebuilder wrote

The nicer and more valuable the car is, the less likely you end up driving it.

YMMV.

I put over 10000km on my 2014 Vanquish in less than six months. 30000km on my first M3T in less than two years.

Cool, so the Vanquish is your daily driver. I picture you like Magnum PI or Miami Vice! 👍

JoeyO wrote

Cool, so the Vanquish is your daily driver. I picture you like Magnum PI or Miami Vice! 👍

Don’t really have a daily, rotate between all my cars. Just really like driving my cars 😆

N1rve wrote

Windshield PPF is not recommended unless it's a car that is RARELY driven. It's also not cheap.. in my area to do a front windshield it's ~700 dollars and you probably would need to replace it yearly if not earlier if it's daily driven and wipers are used on it. That's why there is only a 1 year warranty on windshield PPF compared to 10 or 12 year on normal paint PPF.

I PPF'ed my windshield, and then use a good windshield rain "protectant" like one of the below. I drive my car year round, though I do avoid driving in the rain as much as possible (so I don't use my wipers much). But when I do, I pre-treat the windshield with one of the below the night before or right before I drive, and then try to leave lots of space up front. Regular road dirt kicked up into the rain drops, and onto your windshield, it can cause the wipers to mar the PPF.

I've had my car for 5+ years, 125,000 miles, LOTS of road trips, and have replaced the windshield PPF 3 times so far. So it's an extra cost, but I do like having some base level of protection.

Aquapel: A favorite among auto detailers; it chemically bonds to glass, lasting about 6 months, and is highly resistant to car wash chemicals and wiper friction.

Gtechniq G1 ClearVision Smart Glass: A heavy-duty, long-lasting coating that frequently outlasts Rain-X by miles (sometimes providing up to 20,000 miles of visibility) and is excellent at high-speed water shedding.

Griot's Garage Ceramic Glass Coating: A more user-friendly DIY ceramic kit that provides fantastic hydrophobicity and can also be used on side windows and shower doors.

Emily172013 wrote

I had to replace the windshield on the M340i in the first year. I was on a highway in Colorado and a muddy pickup pulling a horse trailer cut in front of me as I slowed to let him in. Bad decision. My insurance pays for OEM glass the first year.

You're not driving your M car correctly if a pickup pulling a horse trailer can overtake you