2020 GMC Sierra 1500 Brake System Failure; Looking for advice.

[Ehalljr]

I have a 2020 GMC Sierra 1500 that I bought new in 2020. I am, of course, outside the 3-year warranty period, but I only have 41,000 miles on the vehicle as I have a very short commute daily and rarely use the vehicle on the weekends. Very light duty use all around. 

 

While driving ~55 mph down a 3-lane road the brakes suddenly applied themselves and I had to avoid being rear ended by the sudden deceleration. I could start to smell the brakes and I avoided traffic and got pulled into a gas station and turned off the engine. Did a walk around of the vehicle but did not see anything wrong.  When I shut the engine off, there were no engine light/warning messages displayed. 

 

I restarted the engine, again, no engine light/warning messages were displayed. I put the vehicle into drive and eased forward and then in reverse and everything seemed ok, so I proceed to continue home ~ 3 miles. 

 

A few moments later ~ ½ mile, the truck felt like it was dragging the brakes, not the same hard braking as before, but even a slight release off the accelerator pedal caused the truck to slow down measurably.  Then the dash warning message started to appear: Service ESC, Steering assist reduced, Service trailer brake system, Brake system failure – speed limited to 43 mph.

 

Then I had to slow down for a red light and when I pressed the brake there was no power assist in the braking system. I had to swerve to avoid rear ending the car in front of me. I had not driven a vehicle without power brakes since driving on old farm truck as a teen, but that is what it felt like. I was putting all my body weight on the brake pedal to slow down.  After that, I drove very slowly the rest of the way home, standing on the brake pedal every time I needed to stop (and only stopping when I absolutely had to).

 

I am wondering if anyone has had this same issue? I've called the dealership to see if there were any active recalls on the braking system for my vehicle and they said there were no recalls. I have driven 20-year-old vehicles that have had no issue with the brakes and here my vehicle is just over 40K miles, and I came close to getting in multiple accidents due to the brake failure. I am beyond disappointed and frustrated. 

 

Looking for advice from anyone that may have had this occur to them. If I could find the root cause, then I can decide if I can just replace all the brake parts myself and save myself (and my wallet) a beating from the dealer.  What is the best way to approach asking for some good will repair from GM if I decide to go the dealer route? In the last decade, I have had (all brand new off the lot) a mid 90's Silverado, a Colorado, a Chevy Cruze, Traverse, and an Equinox between me and my wife, and this is what I would call the first real issue that we have that I am concerned about. It may end up being a deal breaker since if I had my wife and kids in the truck with me when this happened, I would be a lot more upset about putting them at risk.

 

Thanks for listening to me rant. Any advice would be welcome. 

 

[puppykat33]

I just had a similar issue yesterday on 2020 1500 5.3. But my brakes didn't apply, there was just no brake pedal and I almost ran into an intersection. I had all the codes come up service esc, trailer brake, etc. Knowing that these trucks are extremely finicky with low-voltage batteries I put my Noco battery charger on it to see what the volt percentage came out to which was 25% . Not the best reading but the only one I could get at that moment. I cleared all the codes and left the charger on until it read 100%. I Drove it a short distance and everything seems fine so far but man GM has got to get this fixed before someone gets seriously injured with no brakes. A Low battery voltage battery should never disable brakes if that is the cause.

I need to drive it more to see if it is truly fixed, but from everyone who has posted similar issues like this none have ever gotten a for-sure cause. The codes that came up on the scan tool were the ones that everyone gets but, the thing that stuck out to me was comm error low voltage across multiple modules which made me check the battery first. I hope this helps. Hopefully, someone who has gotten a good answer will chime in...

[Ehalljr]

Dealer said mine was issue reported under Service Bulletin 20-NA-07. They said the issue was a temperature mis-match and that the fix was to re-program the brake module. The service bulletin was published in 2020 I believe. Not sure why this has not made it into a recall yet. 

 

I called GM customer service to start a case to try and get it covered since it happened within 5000 miles of the warranty period.  They paid about 80% of my towing cost and $20 of the $320 dealer cost to reprogram. I've complained multiple times and have tried to appeal the decision but have gotten nowhere.  

 

I am in disbelief that a vehicle that has not been abused, or even used rough would have that sort of critical failure so early in its life. I would NOT recommend anyone buy a GM product after my experience. I am hesitant to drive it anywhere now with my wife and kids due to the safety concern.

 

The best I got from GM representative was an offer for GM loyalty points towards merchandise or a new vehicle. Like I would seriously consider buying merchandise or accessories from GM and advertise for free after they would not stand behind their product. They likely lost a lifetime customer.