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2020 GMC AT4 Garbage Brakes!

SVAT4

By SVAT4
in 6.6L Duramax Diesel (L5P)

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SVAT4 New Member

SVAT4

Posted
Posted

I purchased a 2020 GMC AT4 3500 in September of 2019, since day 1 my brakes have squealed, squeaked, whatever you want to call it. I paid over $75,000 for this garbage track and the brakes make obnoxious noises and frankly it is emabarrassing!! I took it to a local GMC dealer who said....take a guess.....There is nothing mechanically wrong with the brakes and they could not replicate the noises, BS. I brushed it off and around February I ordered new brake pads and decided to do it myself, well the pads were the wrong ones and I have not been able to find an aftermarket set to this date. Since a year has now gone by I decided to go to another dealer because I found a service bulletin on this website (THANK YOU!) # 20-NA-020 that looked like my ticket to getting rid of this simple problem. Well I took it in and guess what the lazy "salesman" service guy said....yes, the same f'ing thing, there is nothing mechanically wrong with your brakes, however they are overheating and we can replace them for $700!!!! They squeak when it is cold most of the time! I have owned Chevy's, GM's for over 30 years and this will be the last time, I hope this stirs the pot and others realize how stupid these service centers are, yes I am sure Ford and others are the same but seriously there is a service bulletin for this that clearly states what the remedy is and they know that! This is ridiculous like the other posters have said about these brakes. $75,000 and my daughters $20,000 Honda Civic is less embarrassing to drive.

  • Haha 1
Tomato Enthusiast

Tomato

Posted
Posted

There is a TSB authorizing dealers to replace pads under warranty for this...

  • 2 weeks later...
MrGraff Enthusiast

MrGraff

Posted
Posted

Looks like I'll have to get this done on mine, they tend to squeal at low speeds especially in drive throughs.  Although I'm not sure I want them to just replace pads and do nothing to the rotors.

redwngr Senior Enthusiast

redwngr

Posted
Posted
 

Silverado HD/Sierra HD Brake Squeal

August 24, 2020

Some 2020 Silverado 2500/3500 and Sierra 2500/3500 models may have a brake squeal condition caused by the low scorch friction material used on the original brake pads.

New brake pads are available that have a high scorch friction material to reduce the potential for noise. Replace the front and rear brake pads with the new pads.

 

TIP: Each brake pad has an Inner or Outer label to indicate where it should be installed. (Fig. 6)

 

F06-brake-pads-1.pngFig. 6

 

If the pads are replaced and the squeal sound continues, check the orientation of the pads. If the inboard and outboard designation on the pads indicate the pads are installed in the wrong location, the squeal sound may persist.

Keep in mind that only the left side of the truck has the wear sensors, which are mounted on the inner pad. (Fig. 7)

 

F07-brake-pads-2.pngFig. 7

 

Refer to Bulletin #20-NA-020 for additional information and part numbers.

Chris2087 Enthusiast

Chris2087

Posted
Posted

I had mine replaced today per the TSB, they really don't need to turn the rotors unless there is a groove or uneven wear.  Mine where smooth so they didn't turn them.

  • 7 months later...
Dave M. Enthusiast

Dave M.

Posted
Posted

I'm dealing with this same issue. Sure am glad I checked this forum... was about to order some new pads and saw the TSB about this. Calling the dealer tomorrow. 

  • 6 months later...
M1Andrews New Member

M1Andrews

Posted
Posted

Hate to be the bearer of bad news, but I'm well versed in this saga.  As I'm not sure that the replacement brakes are any better than the original ones...  I've had my 2020 AT4 replaced twice (front & rear) and embarrassed to go back for a third time as the brakes still squeak.  

 

Hoping for aftermarket options that may be better, as I REALLY like the truck, if the brakes were quiet.   

  • 2 weeks later...
redwngr Senior Enthusiast

redwngr

Posted
Posted
On 12/25/2021 at 9:42 PM, M1Andrews said:

Hate to be the bearer of bad news, but I'm well versed in this saga.  As I'm not sure that the replacement brakes are any better than the original ones...  I've had my 2020 AT4 replaced twice (front & rear) and embarrassed to go back for a third time as the brakes still squeak.  

 

Hoping for aftermarket options that may be better, as I REALLY like the truck, if the brakes were quiet.   

Maybe they didn't read the bulletin.

 

  • 2 months later...
pokismoki Senior Enthusiast

pokismoki

Posted
Posted

yeah the pad materials are mostly the culprit of the noise, which probably performs better than the 1500 brakes, better bite.. even racing brakes are loud and squeeky, its a trade off in performance and fade resistance

Truston Gunter Enthusiast

Truston Gunter

Posted
Posted

So I have a 2020 Sierra HD with this same problem. According to the dealership, this is NOT covered under the bumper to bumper warranty and is ONLY covered for 7,500 miles regardless of any service bulletins.  . Well my truck has 21,908 miles and guess its my fault for not taking it in sooner thinking I had 3 years / 36,000 miles for any "manufacture defects" to be corrected. Very disappointed however, I would like someone to verify this is true and not just the dealership being...... how can I say it nicely...... "ill-informed"....... Hate feeling like this dealership is trying to not do the work for whatever the reason. 

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