The contact owns a 2015 GMC Sierra 1500. An independent mechanic called on behalf of the vehicle owner, who is deaf. The contact stated that the brake pedal failed to depress and stop the vehicle properly. The contact diagnosed that the vacuum pump and the brake booster system were malfunctioning. The dealer (gulf coast Chevrolet Buick GMC, 1901 w. fm 523, angleton, tx 77515, (800) 593-5226) stated that there were no recalls on the vehicle. The manufacturer was called and the contact was provided a case number. The manufacturer stated that the vehicle had too many miles to be covered by the extended warranty. The failure mileage was 69,000.

- Houston, TX, USA

Hard brake pedal when attempting to stop, happens on hwy with fast speeds, slow speeds in parking garage and in reverse.

- Chesterfield, MI, USA

While driving at highway speed, I entered an off ramp to find no power assist to my brakes. The pedal was extremely stiff. I came very close to having a collision with the car in front of me. I contacted my mechanic immediately, he checked it out and it appears the vacuum pump has failed without warning. I have owned this vehicle since new and have had no problems with it until this issue.

- Arkansas City, KS, USA

I was backing up and the brake pedal got hard and would not stop the truck. I tried to go forward and the same thing happen.

- Bolivar, MO, USA

Vacuum pump vachose assy brake booster and mastercyclinder failure which cause brake failure while driving. Happened several times until 'service trailer brake' light came on. No brakes, no way to press down pedal. GMC refuses to assume responsibility for repair. Cost: $1311.16

- Mebane, NC, USA

Having issues with hard brake pedal. It happened a few time when the truck was new but could never duplicate it. Twice it almost caused an accident. I have since found a way to duplicate it. When backing a boat trailer down a ramp every time they become hard, I have to ride the emergency brake, but it only happens when the boat is on the trailer. I have researched this over the years but not till recently have I seen other reports of truck with this issue. I have not contacted the dealer yet but will in the next week or so when I can take off to go. I do not now date of first occurrence but I put a random date in 2015.

- Robert, LA, USA

The contact owns a 2015 GMC Sierra 1500. The contact stated that the vehicle failed to pass state inspection due to master cylinder, vacuum pump, brake booster, and hose leakage. The dealer was not contacted. The manufacturer was notified of the failures. The vehicle was not repaired. The failure mileage was approximately 33,000.

- West Kennebunk, ME, USA

When brakes are applied the pedal is hard and vehicle does not stop. It seems to happen when going slow for example in parking lots etc. I have read other articles where people are experiencing same thing at high speeds. It does not happen all the time, but it started 7/1/2018 and I've experienced this four times now. Took to dealer this morning they refused to look at articles explaining what I've found.

- Hendersonville, TN, USA

While in motion the brake pedal goes hard and is difficult to stop. I believe this is the cause of a low speed incident I had earlier this year. The issue occurres mostly at slow speeds in stop and go traffic. If feels like the brake booster fails and the pedal is bottomed out. It happens frequesntly while hauling a trailer in reverse. Very dangerous situation.

- Harrison Township, MI, USA

Brake failure due to bad vacuum pump

- Darien, CT, USA

While driving in stop and go traffic speeds there have been a number of occasions that the brake pedal goes hard and the truck will not stop. I have noticed on other forums that this seems to be a common issue.

- Rocky River, OH, USA

I was driving down I20 in dallas in rush hour traffic, the traffic was heavy but moving at 70 miles an hour. I saw brake lights in from of me, when I pressed the brake to slow down the brake pedal was hard, I could not press it with one foot and I could not slow down. I finally was able to slow down by putting both feet on the pedal with all my weight it felt like it was forever before I was able to slow down. I thought I was going to be unable to stop.I drove another 15 minutes going very slow and scared. Parked my truck in the drive and had a tow truck pull it to the dealership closest to my house. My truck only has 58,000. I really was scared for my life if you have ever driven in rush hour dallas traffic you understand. I could have lost my life or be seriously injured. The dealership told me today they had not heard of this issue. The dealership said they doubt GMC can do anything about the problem. The service department said was a vacuum pump on the breaks. I looked on line and others have reported this same issue. I could have been killed. Still shaking over the incident. I hope this problem is addressed before someone is killed

- Mesquite, TX, USA

Brakes loose boost at idle after towing trailer. I towed a heavy trailer and then dropped it in my yard. When I went to move my truck down my driveway and into my garage I had no brake boost unless I revved the engine.

- Grandville, MI, USA

I was following my daughter who was exiting the gas station and pulling out onto route 149. As she pulled up to route 149 she stopped to check traffic. I was behind her in my 2015 GMC Sierra 1500, going approx. 2 mph. When I hit the brakes, nothing happened. The truck kept moving forward and I hit the rear of my daughters car, cracking the rear bumper. No damage to the truck because I was only going a couple mph, luckily my daughter had her foot on the break of her car, otherwise I would have pushed her right into oncoming traffic. The fact that she had her foot on the brake is what stopped my truck. We both backed up and got out of the intersection, when backing up the brakes worked fine. There wasn't a spot to leave the truck so I had to drive 3 miles back to my house. The brakes worked perfectly after, no issues what so ever. It seemed like at the slow speed that brakes didn't have any boost (or pressure), the pedal was very very stiff, it felt like it was pushing back against me when I hit the rear of my daughters car. But driving home everything worked perfect. I'm bringing the truck in (approx. 72K miles) to have it looked at but I'm concerned the dealer will not know what to fix as the issue seems to be intermittent. This was a very dangerous intersection and I could have pushed my daughter into oncoming traffic and the result would have been much much worse. Something seems to be seriously wrong with the brakes and when googling this issue, I found many similar issues/complaints regarding the brakes.

- Moodus, CT, USA

Takata recall when backing up brake pedal is not at its normal pressure seems to be all the way down so have to press brake harder to stop the truck when I shift to drive forward same thing applies. After truck has been off for some time parked then start to drive brakes seem to be working fine.

- Pearland, TX, USA

Brakes became hard to depress and engage while vehicle was moving. Almost crashed vehicle. Afraid to drive. Brought to dealer. Said it was bad brake booster. After doing some research, found out should replace vacume pump, master cylinder, hose line, etc., so I did. 44K miles, 3 year old truck, happened on /12/10/17 brought to dealer garber GMC in Florida for $1300 repair on 12/11/2017. No warning signs when this happened. Very dangerous when brakes fail while vehicle is in motion.

- Port St. Lucie, FL, USA

I was pulling into a parking spot at work (slow speed) and I could not stop the truck. I kept applying more and more pressure to the brake pedal and it did not stop the truck. The truck hit the curb and stopped, luckily there wasn't a another car as I would have hit it. It caught me a bit off guard as I was trying to figure out what just happened. I backed the truck up about 10 feet, brakes worked fine in reverse, and pulled forward back into the spot. Again, the brakes did not work and I again I hit the curb. No damage to the truck, but brakes did not work. It felt like the brakes were pushed back against me. Brake pedal never went to the floor, I pushed the pedal and there seemed to be more resistance than normal. It didn't matter how much I pushed, the truck kept moving forward. This happened with approximately 78,000 miles. I was late for a meeting so I went into work and later in the day I had a break so I checked on the truck. Pulled out of the parking spot and back in and brakes worked both in reverse and in forward. So now what to do"???????" at work I did a quick google search and saw this similar issue come up in a lot of the search responses- and decided to log it here. This is a huge issue and very dangerous if I was in a crowd or people or at an intersection and couldn't stop. I called GMC and they said they never heard of anything like this- they didn't seem to care, they said if I brought the truck in they would see if it happened again.

- Moodus, CT, USA

We want to report a safety feature in 2015 GMC Sierra 1500. We bought a vehicle brand new and it currently has about 40,000 miles on the odometer. On 11/4/2017 after we got off the interstate 10, the break from this truck stopped working, we had a difficult and dangerous time to make it stop, and was lucky to manage to get into a store's parking. We have to haul it to the local GMC on Monday and found out the break pump was bad. This problem could cause a deadly accident if we were still in the freeway. We called GMC to report the problem and they said there is nothing they can do. This problem is serious and need to be addressed.

- Pensacola, FL, USA

Out of no where, I had to use extreme pressure on the pedal to stop the truck. The brakes began to sound rough. I turned the truck on and off hoping that would fix the problem. It didn't, I took it into my GMC dealer to find out that the vacuum pump has failed for the brakes. I did my research online and noticed many people have had the same issue. I was surprised there isn't a recall on 2014-2016 GM vehicles. This is dangerous and I'd hate someone's brakes failing at high speed and someone gets hurt.

- Clarksville, TN, USA

2015 GMC Sierra - braking becomes very difficult at idle speed whether moving forward or reverse. Brake pedal becomes very difficult to depress. Vehicle will move a few feet until completely stopped even with forceful pressure on the brake pedal. Appears to lose all vacuum/power braking ability.

- Weston, FL, USA