Was driving with 7 children in my car, going 35 mph, when the dash message of "service brake assist" flashed on the screen. I was not using the brakes when this message appeared. I started slowing down, brakes worked fine, but then came to a red light and could not stop. Complete brake failure! When I tried to press the brake down, the pedal felt like a rock was stuck behind it. I repeatedly pressed it hoping to get the car to respond, but nothing! I jerked the car into park, the car made a grinding noise and then jerked to a halt. I pulled into a parking lot, tested the brakes several times, they worked fine. I turned my Suburban on and off, pressed down the parking brake, released it, then tried the brakes a few more times. Nothing out of the ordinary. I got back on the road (I know, stupid, but I had to get kids home and didn't really know the extent of the problem) and the brakes failed twice more, both at slow speeds, like stopping at a stop sign, or traffic light. I called the dealership that services my Suburban (VanderGriff Chevrolet in Arlington, TX) and made an apt. to drop my car. Because the brakes were not failing every time, I thought it might have been an electrical thing, no grinding, no squealing, no indication other than the feeling that I got at low speeds and that was manageable with slowing way down before I came to a stop and then if need be, throwing it into Park. So, I made a HUGE mistake and tried to drop my kids off at practice after the car had been resting for a couple of hours. I still thought I could take it to the dealership that night and drop it off, using back roads and going slow, so driving 5 minutes from the house doing the same thing was no big deal. We experienced a Complete Brake Failure, and no throwing it into Park this time. I was so scared I was going to kill someone I immediately pulled into a parking lot, and at 5 mph could not stop my car. I had to find a spot that was slightly uphill to stop my car. I had it towed, and the dealership says the repairs would not be covered because I was over my warranty. This car is not even 3 years old and only has a little over 60,000 miles. This is not a "wear and tear" problem. My car is "under diagnostics" and I won't hear back for a few days to see what the problem is. In the meantime, I've been researching it myself and it seems I am not the first person to complain about this problem. I'm going to report this issue to GM, the Attorney General, and the BBB because this failure puts people in imminent danger.

We complained about this brake failure multiple times and were told the brakes were fine. Only after the warranty expired and serious concerns for the safety of my kids did they agree to fix for $1300. We have had several friends with the same issue--all unresolved, GMC is not taking this seriously--a fatality is sure to come but no concerns from the company. This was a $75k vehicle--we are sickened by their lack of interest in such a life threatening problem. Will never purchase a Chevrolet again now that I have read all these brake issue problems unresolved.

Was driving through Chik-Fil-A to get my family dinner and the car wouldn't stop at the register in the drive through. Then again at the window the vehicle went past the window. I was able to get it into a spot. In looking online, it appears to be the brake booster. My step father is a mechanic and drove in and agreed that the brake booster was the issue and stated that it wouldn't be covered under the warranty! This is ridiculous because my mileage is only 38805! Luckily we were driving slow when it gave out or my son and I would have been seriously injured on the highway! After reading all these complaints, it seems this should have been a recall! This is a serious problem!

We have a 2015 Suburban with 51k miles on it. All of a sudden our brakes wouldn't work. There was no warning or any signs this would happen. My wife was driving with our kids and almost struck a vehicle. This was deeply concerning so we immediately took it to the dealership. They told us the entire vacuum system would need replaced for the brakes to work again. They stated this wasn't normal but GM wouldn't cover it. I called GM because I believe this should be under warranty. GM told me because of the mileage I was out and on my own. I asked for assistance because I've ownded several GM's and they said no. I am very upset a 70k dollar vehicle has these defects. GM doesn't respect its customers!