I have a 2014 C7 Z51, and I have periodic brake squealing. When it first started happening the dealership installed "redesigned" front pads on front; however, now it sounds like the brakes are squealing and even grinding a bit on the back/rear. It happens about once every 15-30 stops.

My car only has about 8K miles. The dealership is basically now saying the brake squealing is just part of owning a car with high performance brakes, but it is embarrassing and gets on my nerves.

Has anyone else experience this? If so, what did you do to fix it.? The pads have plenty of meat left and look almost new. The car is out of warranty. I have tried to blow out any brake dust with compressed air, but this didn't help.

 

Brakes don't squeal as a Normal thing. IF they do, something is wrong. Did you buy the car new? I have the dust free pads on my 4 corners and no squeal and no dust.

They aren't telling you the truth.

Elmer

 

Try taking the car to an independent mechanic who knows how to troubleshoot. The dealers specialize in selling and replacing parts, not troubleshooting and repair. I'm surprised the dealer's service advisor has not tried to blame the problem on the fuel pump and advised you to replace the gas tank. Yeah, they get that ridiculous.

 

Two solutions. The first cheap, the 2nd best with a Z51!

After I put on the 500 miles and was easy on the brakes in my Septer 2013 built Z51, at ~1000 miles they would occasionally sequel like a stuck pig on some slow speed stops! I bedded the pads per the GM recommendation for Tracking a Z51 etc. (For whatever reason GM calls in burnishing but you can google bedding and lots of info on the internet. In fact a recent article said you have to use performance brakes aggressively from time to time to avoid patches of built-up pad material on the rotors. That causes vibration and noise! Note this is a very thin layer, you worn't see it.)

How to burnish in the Owner's Manual BUT I only did about 10 stops not the 25 recommended if Tracking. Need the space and little traveled road to do it. For 9 months no noise but there so much dust I was washing the wheels every ~100 miles or the dust was pitting my black wheels.

I bought Carbotech 1521 pads. Made in the US and they worked great. 85% less dust and what was there did not pit my wheels! Washed the wheels when I washed the car! No noise!

Installed Carbotech 1521s on my new Grand Sport and same result, stops great, even better that OEM when cold and as good when hot. However they are NOT for Tracking.

 

My Sept. '13 built Z51 did the same thing starting at about 200 miles. I waited until about 500 miles and did the burnishing/bedding procedure and like Jerry only did it for about a dozen stops. It quit squealing and has never come back.

 

On my 2016 base car, I'm getting a very loud squeal when I back out of my driveway and hit the brakes after sitting overnight. No squealing after that. Car has 11,000 miles, rotors mirror finish and almost no brake pad wear.

 

I did buy the car new.

 

Try the carbotech dustfree pads. 1521

Carbotech™ 1521™

The Carbotech™ 1521™ is our high performance street compound. The 1521™ compound is known for its release and modulation, along with unmatched rotor friendliness. 1521™ is also a very low dusting and low noise compound with an excellent initial bite. This compound's excellent linear torque production provides incredible braking force without ABS intervention. Carbotech™ 1521™ operating range starts out at ambient and goes up to 800°F (426°C+). 1521™ is suitable for ALL street cars, perfect for your tow vehicle or fleet vehicle. Carbotech™ 1521™ is NOT recommended for ANY track use.


Elmer

 

What does the burnishing/bedding procedure entail exactly? I've don't know anything about how this works. Thx!

 

Some hard stops done many times and then a drive without stopping to let the brakes cool. I think it's in the owner's manual.

Elmer

 

Owner's Manual:

1. Apply the brakes 25 times
starting at 100 km/h (60 mph) to
50 km/h (30 mph) while
decelerating at 0.4 g. This is a
medium brake application. Drive
for at least 1 km (0.6 mi)
between applying the brakes.
This first step may be skipped if
there are more than 320 km
(200 mi) on the brake pads.
2. Repeatedly apply the brakes
from 100 km/h (60 mph) to
25 km/h (15 mph) while
decelerating at 0.8 g. This is a
hard brake application, without
activating the Antilock Brake
System (ABS). Drive for at least
1 km (0.6 mi) between stops.
Repeat until the brake pedal
travel starts to increase.
Depending on conditions, this
should take no longer than 25
brake applications.
3. Cool down: Drive at 100 km/h
(60 mph) for approximately
15 km (10 mi) without using the
brakes.
4. Apply the brakes 25 times from
100 km/h (60 mph) to 50 km/h
(30 mph) while decelerating at
0.4 g. This is a medium brake
application. Drive for at least
1 km (0.6 mi) between
applications.

 

Are you tracking the car?

If not swap pads..

The Carbotech Bobcat 1521™ is our high performance street compound that is our most successful compound. The Bobcat compound is known for its awesome release and modulation, along with unmatched rotor friendliness. Like our AX™ & XP™ line of compounds, Bobcat 1521™ is a Ceramic based friction material offering minimal rotor damage and non-corrosive dust. Bobcat 1521™ offers outstanding performance, even when cold, low dusting and low noise with an excellent initial bite. This compound’s virtually perfect linear torque production provides incredible braking force without ABS intervention. Bobcat 1521™ operating range starts out at ambient and goes up to 900°F. Bobcat 1521™ is suitable for ALL street cars, perfect for your tow vehicle, police cruiser. The Bobcat 1521™ compound has been found to last two-three times longer than OE pads you can purchase at a dealership or national retailer. That’s one of the beauties of Carbotech Ceramic brake compounds. Bobcat 1521™ is NOT recommended for any track use.

 

Walt, my 2015 base C7 did exactly the same thing. So, I got in the habit of using the leaf blower to dry the car, really blowing a lot of air over the wheels/rotors /calipers etc AND then driving it with some brake applications. Nothing helped.....always squealed backing up out of the garage.
So last June I took delivery of my 2018 base which now has 5200 miles on it and I am now in Florida washing the car once a week. I still blow dry the car/wheels after washing but never drive it to dry the rotors/pads.
......AND IT HAS NEVER SQUEALED ONCE ON BACKING OUT OR ANY OTHER TIME .
The only obvious difference I can see is the 2015 had very polished looking rotors whereas the 2018 is a very dull almost iron looking finish. There have been issues/bulletins/ and posts previously with this issue. I wonder since this is a known issue to GM if they have made some kind of change to the calipers or pads or rotors ???
There is a bulletin your dealer should have that describes the complaint and requires a special lube to be used on the ends of the calipers . I believe the squeal you are hearing is not the result of minor surface rust but rather from the vibration of the pads ...if memory serves.
If you are still under the BtoB warranty maybe you can get your dealer to do the bulletin for you.....good luck with a fix.

Doug.

 

Mine was totally quiet at 10,000 miles and then it started. Any idea what the Bulletin number is?

 

I'll see if I can find it .

 

Walt GM bulletin PI 1258: Brake squeal or squeak noise intermittently on initial brake application.

Also in our forum look for the thread I started 11-27-2014, titled "Brake squeal 2015 coupe" and you will find a copy of the bulletin in post # 9.

The bulletin may be superseded by now but as a starting point you could show the 2014 bulletin to your service writer just in case they have no knowledge of this issue. As I said before it is well known to GM .
This problem is worse on the cars with the high performance brakes like the Z51 OR Z06 cars from 2014,2015, maybe 2016 but don't know the model years for certain.

Also if you google the bulletin there is lots out there.

Doug.

 

I have a 2014 Z 51 also, mine squeeled occasionally for the first 1,500 miles or so. Not sure why it did, or what made it stop.

 

If it just happens when you back out of the garage in the AM, perhaps 3 or 4 few hard stops will make it stops in a row will get it to stop. May be too easy on the brakes.

Yep, dealers get paid to do that! It may last for a short while! Dealer's can't bed/burnish pads! You have to do it yourself! Even if they would, GM would not pay for the service!

Best solution is Post #12 for those with a Z51, Grand Sport or Z06. If you don't do your own work buy the pads and pay the dealer to do that. Those pads will work for the base car but brake dust is not an issue with those pads.

Then consider posts 4/5/8/11. Putting some lub on the sides of the pads will make you feel better for a while!

If you don't want to swap pads the bedding puts an even layer of pad material on the rotors so that you don't get the slip/stick that causes vibration and squealing. With a car with high performance brakes you need to apply them aggressively from time to time to maintain the uniform thin layer (note it is not visible!) It's fun and legal to stop fast occasionally!

Google bedding brakes, lots of longer better explanations.

 

Actually bedding the brakes is on my list as the first thing to do as I have done with other brake squealing problems. It's always worked before. I just have to wait a little for the weather here in the Philly area to improve enough to take the Vette out.

Doug, thanks for digging into this.

 

I would be worried with the " installed "redesigned" front pads ". Do they have the weights as the originals do (at least on Z51)? See pictures above.


Regarding the dust I can seriously recommend the PowerStop Z26 (pic 2). No dust anymore and they also have the weights to minimize vibration and squealing.


//Motors5