I currently own two 2022 GLCs. The first one was purchased almost a year ago, November 2022. I live in New York so therefore the weather is just beginning to turn a little cooler. With the first GLC shortly after I purchased the vehicle I noticed a rather loud high pitched squeal when backing out of my garage in the colder mornings . Having owned a 2017 and a 2018 GLC , I should have been used to it. Anyway, I took the GLC purchased in November into the dealer and they replaced the rear brakes and rotors, it did help a bit, not completely.This morning the weather was pretty cool, 43 degrees Fahrenheit and my second GLC, this one purchased in June 2023 was squealing loudly. One would expect a prestigious brand such as Mercedes Benz would have been able to rectify this issue given 6 years of customer complaints. The dealership has told owners that it is not a safety issue, it isn’t, however, it’s a quality issue and as I informed my dealer with my other GLC, a MB should not sound that way. He had no choice but to agree.
I am certain that I am just one of many GLC owners experiencing this situation. Has anyone been able to rectify this issue with MB where the brakes do not wake up the neighborhood each morning? I know that the rotors get some kind of rust buildup and only after the brakes are applied several times does the squeal go away. BTW, I also own a 2021 GLE and it has no issues whatsoever, so therefore Mercedes can build a vehicle with quiet brakes. Any recommendations that have resulted in positive results, thanks.

 

Usually, squeaking brakes are caused by driving habits.

Once the pads build up a glaze, they don't stop as well, and they often squeak/squeal.

Just to rule out that possibility, and potentially save trips to the dealer, try bedding in your brakes, as you mentioned.

Find a very vacant stretch of road, drive 60 mph, slow HARD to 10 mph (not zero), repeat two or three times.

See if that improves or fixes things, and if it does, you have found the problem. Sometimes just eliminating that glaze will be a permanent fix.

 

Thanks for your reply, it is a build up of some sort on the surface of the brakes. After using the brakes a few times on my way to the highway the squealing sound gradually disappears and is gone for the rest of the day. The next morning, perhaps weather dependent, the noise may reappear. I realize it is not a safety concern, however, it does concern me that this issue has persisted for years with the GLC. A problem that has persisted over several years, where there must be a relatively simple fix, must reflect on the substandard quality control of this luxury brand. I am fairly certain that the braking system in my GLE is not that much different yet those brakes are quiet. My feeling is that almost all current cars now being manufactured are pretty good, unlike many years ago where there were some unreliable models. In terms of reliability and quality control of all vehicles, the bottom has certainly come way up, however, I don’t think the top has moved much, if anything a little lower. I’ve been buying Mercedes for years and have enjoyed all of them, I’m just wondering if I might be buying them just because it’s called MERCEDES BENZ.

 

I think we are talking about different things.
You're talking about bedding the brakes, but I'm talking about Glazing of the pads. If they build a glaze, they just won't bed in, which sounds more like Glaze than bedding by your description.

You have to break that glaze. It can be done by removing the pads and wire brushing them, or by using the aggressive stopping technique I described earlier.

I'll bet the driving habits are more gentle on the GLC than the GLE. Different drivers?

 

You are correct, different drivers, and the GLC is driven more gingerly than the GLE.

 

I thought the squeaky brakes on GLC were simply because MB hasn't figured out how to make a pad that's quiet when cold? It's mentioned constantly in GLC reviews since 2016.

My pre-owned came with sqeaky brakes freshly installed by the dealer. I don't blame them- customers can't complain about fresh MB parts.

Hasn't anyone here figured out the aftermarket pads necessary to stop the squeaking? Surely they exist.

 

If your driving happens induce squeaking with factory pads, it's likely that you'll have the experience with whatever you choose in the future.

Do some research on brake pad glazing.
Or do a series of aggressive stops and probably fix it.

 

The GLC has had endless reports of squeaking pads when cold, especially in reverse. It goes away when the brakes warm up a bit. Unless the parts come factory glazed, this isn't caused by glazing. Most people speculate it's simply the layer of rust forming on rotors while the car is idle.

I'm a sedate driver. Most certainly I am not overheating my brakes to glaze them.

Hard stops is an unusual recommendation to remove glazing. Most common advice is to sand the rotors & pads to remove the glazing. But I'm happy to wait until the pads wear out, and trying a different pad next time.

 

I should have said 'bedding in' brakes instead of glazing. Overheating isn't the only reason for pads squealing.

Most often, it's sedate driving, and not heating up the brakes enough.

This can be corrected by the hard stopping that I mentioned above, to bed in the brakes.

There are plenty of YouTubes and articles about it. Here's the first one I found:
https://www.jdpower.com/cars/shoppin...20new%20brakes.

 

I have the same squeaky problem in my GLC 300 (2017). I bought the vehicle in December and didn't notice the issue during the first year. It started in the second year, and the noise has gradually increased. It is embarrassing as the squeak has become so loud that it can wake up the neighborhood in the morning. I try to sneak through like a thief, moving slowly without applying the brakes, but I have to when I back up from the driveway to the road. It is horrible in the winters. The service department didn't fix it or acknowledge the issue because, by the time I reach the dealership, I would have driven 11 miles, and the issue would have gone. I have been living with this issue for 7 years now. It's really poor-quality brakes from Benz and poor on the service department to ignore the issue, even though they know about it. This may be one of the reasons I may not buy a Benz or upgrade to a new GLC again, even though I have liked the vehicle in all other aspects

 

I just changed the rear brake pads and rotors on my 2021 GLC300 4matic past weekend. Got tired of the sqeals on cold mornings starts in reverse gear. I left factory setup to Akebono (Eur1872) pads with Powerstop Evolution fully coated rotors (EBR1650EVC). I measured an average of 6.5mm of pad remaining on the MB pad after 52K miles. It appears that OEM used a thin film of white brake paste in the slide pins versus a generous mess of sil glyde. One side/set exhibited some wear. Thankfully, I had new sets just in case. The rotor wear pattern on that side were quite different as well.
My Autel MX900 was very handy in putting the brakes in service position. Saved me from following videos to copy pushing sequences of buttons on the steering wheel. Everything else was pretty straight forward like any other floating caliper brake service. It's really tight to torque the caliper bracket bolts. You'll need a low profile swivel on your torque wrench. I recommend having a serpentine belt tool kit with a digital angle guage to set the second half of 60Nm+45° unless you're not setting the torque. I didn't find one YouTube video mentioning it but now you know.
All in, this job was $250 parts. I really took my time and cleaned up the caliper and bracket thoroughly. More than most. I made sure to lube every metal to metal contact point with brake paste. I put in 6 hours including bedding the brakes. My local dealer charges $1100. I don't work on my car to primarily save money. I enjoy it. If this works out worse than factory, I will go back to MB setuo by spending around $330. That's still roughly half what the dealer charges. Akebono Euro gets great reviews on many forums so it gives me hope.
It going to be fairly cold next few mornings like teens and 20s. I will let you know.

 

You're driving too gently, which will build up a glaze and cause the squeaking that you're experiencing.

Try bedding your brakes, which involves a series of very aggressive stops from 60 to 5 mph. There are plenty of sources and videos about how to do this.

The more you tiptoe through the neighborhood, the worse it'll get.
Changing pads and rotors will only delay the recurrence.

 

I would not live with this for 7 years. I would try different brand pads or even rotors. Yes, extra cost but heck it's very annoying.

 

It's been one month or less, according to his post.
He should try Bedding the brakes. Free and a likely fix.
Just do it.

 

I don't think it's as simple as that. I had this issue and I tried everything to no avail.

 

Try again.

It's often hard to find enough open road to do a good bedding job.
Slowing from 60 to 5mph (Don't come to a complete stop). Re-Accelerating to 60 and repeating 3 to 4 times is what is needed. I need a few miles with minimal traffic to do it safely.

 

Fair enough hopefully this will work for those still experiencing the issue.
My latest car doesn't have the problem.

 

If it's associated with bedding, why would it squeal only in one direction and not in the other?

 

It's hard to say, but it's likely there's a resonant frequency that's activated at one speed in one direction.

 

My wife's '21GLC squealed in reverse usually as she's backing out of the garage or a parking spot. She's not on heavy brakes while doing that. I backed her car out once, just in reverse gear, I let off the brake, squeals without foot pressure and squeals as I apply brake force. This is walking speed. Is it a stuck pad? But on my '20GLC, never has happened. Both odometers around 50K miles.

Week#1 update - (after new powerstop rotors, Akebono Euro pads and one set of caliper slide pins). Squealed once out of a dozen starts. Compared to right before the switch, it squealed more times than not. Brakes feel better. So far, it's worth the effort.

Factory rear pads were worn 50% (3 to 4 mm) anyway. I'm going after the other caliper slide pins this weekend make sure that's ruled out and matches the other side.