While pulling into a parking lot my brakes failed to stop my truck twice. The brake pedal was very stiff, like it was a manual brake and not power. Had to depress brake pedal very hard to get my truck to stop. I shut off the engine and then restarted and the brake pedal returned to normal.

- Litchfield, MN, USA

At first the issue started as I was parking in reverse, pressed the brakes and the truck did not want to stop until I put a lot of pressure on the brakes. Then pulled forward to check and it did the same thing so I parked the truck and left it overnight. It worked fine in the morning and the next few days. Then it happened again after about a five hour drive home from work I exited the freeway exit 99 in tumwater the brakes got really stiff and was not slowing quick enough for the stop sign coming up, I slowed to about 35mph then realized it wasn't gonna stop so I pressed the brakes as hard I could swerving just past the stop sign until it stopped. Preceded slowly got some fuel and still had about another hour drive home and now the brakes was really stiff and truck would not stop unless I put a lot of pressure on the brakes. So I got back on the freeway going only about 55 mph increasing my stopping distance crawling all the way home having press the brakes extremely hard when I needed to stop for traffic lights. Now I'm afraid to drive the truck anywhere without fearing of the brakes not working at all completely.

- Puyallup, WA, USA

Brake pedal won't go down and is stiff. Brakes don't react.

- Hermitage, TN, USA

Brake booster vacuum faulty. Causing a near miss in drive thru almost rear ending another car. Vacuum pump faulty.brakes become hard to push and get no response. This is a very dangerous. GM needs to have a re-call before people get killed. It is a known issue lots of the same complaints.

- Locust Grove, VA, USA

Break pedal at low speeds locks up completely.

- Georgetown, KY, USA

Brake vacuum pump. At slow speeds my brakes almost don't seem to work. I'm sure it's the same problem I've read about.

- Saint Charles, MO, USA

The contact owns a 2015 GMC Sierra 1500. While backing out of a parking space, the contact depressed the brake pedal, but the vehicle did not stop. As a result, the contact struck a parked vehicle. A police report was not filed and there were no injuries. The vehicle was taken to an independent mechanic who determined that the brake vacuum pump was damaged and needed replacement. The dealer and manufacturer were not notified of the failure. The vehicle was repaired. The approximate failure mileage was 48,499.

- Tylor, TX, USA

Brakes failed. I was backing into my garage and the pedal became really hard to push. I almost did not get stopped before I hit the wall.

- Pleasant View, TN, USA

Yesterday afternoon while backing out of parking spot, my brakes became unresponsive. The pedal was extremely hard to press and would not stop the vehicle. The result was the vehicle rolling down an inclined parking lot and hitting another vehicle. Normal braking had resumed when leaving the accident. This is the second time for the brakes to become unresponsive at low speeds. Approximately 1 month ago the same situation happened driving through a parking lot. Brakes became extremely firm and unable to stop the vehicle. No damage resulted from that incident. After reading several message boards, it appears to be a widespread issue with this vehicle that results in replacement of multiple power braking components. I currently feel extremely fortunate that my brakes did not fail 5 minutes earlier while picking up my child from school.

- Maumelle, AR, USA

Brakes failed to reser at low speeds, resulting in near collision. Brake pedal became stiff and unresponsive. Has also happened previously, was told brake vacuum pump failure is the cause. Was notified this does not qualify under vehicle warranty despite reading of multiple reports of failure, technical bulletin release, and immediate safety issues.

- Falls Church, VA, USA

The contact owns a 2015 GMC Sierra 1500. While driving 1-10 mph, the brake pedal was difficult to depress and failed to stop the vehicle. There were no warning indicators illuminated. The local dealer and manufacturer were not contacted. The vehicle was not diagnosed or repaired. The failure mileage was 80,000.

- San Antonio, TX, USA

Backing up the truck the brake pedal became hard and the truck would not stop like I lost power I almost hit my dog and the garage it was very scary

- Escondido, CA, USA

Vehicle's brakes become stiff at low RPM causing difficulties stopping.

- Goose Creek, SC, USA

On several occasions slow driving in parking lots I have lost power assist braking and almost hit a car parked in the spot in front of me. I have read online about the issue with the brake vacuum pump and am thinking that is my issue. My brake pedal after a few pumps will get super stiff. On every occasion that this happened it was slow moving adjusting into a parking spot and had pumped the brakes several times. The pedal then becomes still and pushing the brake pedal does not get the braking power as expected.

- Macomb, IL, USA

While driving at slow speeds if you tap the brake pedal it won't depress and the truck will keep rolling. This happens when I'm trying to park usually. I was backing in my driveway and it didn't stop after taping the brake pedal 3 times. I hit the telephone pole with rear bumper which bent the body of the left rear fender enough to cause the tailgate to not open. My GMC dealer replaced the faulty booster pump for $1029.35 and I had to rent a car for 2 days.

- San Carlos, CA, USA

Brake vacuum pump booster. First started when driving under 5 mph. The brakes were hard to push down and would not stop the truck properly. Did this for approximately 3 months. Then driving getting off the interstate and applied brakes going 60 mph the brakes would not work. Could barley stop. Same issue has when driving slow. Now the brakes will not work at any speed. They truck is undrivable until it gets fixed.

- Prairieville, LA, USA

At low speed and on a number of occasions, the brakes have seemed to lose power and it required a lot of brake pressure to stop the vehicle and avoid hitting another vehicle, my garage, etc. It had been happening intermittently over the past month or so. Went in to the dealer and they replaced the vacuum pump at a cost of approx $600.

- Scottsdale, AZ, USA

Very difficult to stop the truck while going at a low rate of speed 5 to 10 mph. Had to forcefully apply pressure to the brake pedal to get it to stop still required more stopping distance. Brakes did not become fully functional until after placing the vehicle in park and shutting the vehicle down waiting for approximately 15 minutes. Restarted the vehicle and brake were functioning properly. This event occured at approximately 46,000 miles on the vehicle. Following day brought the truck into the local GMC dealer and verified that the truck has a braking problem found a leaking brake booster and master cylinder.

- Port Angeles, WA, USA

Vacuum pump failed at 58000 miles. Lost brake assist at parking lot speeds. Could have caused an accident.

- Fontana, WI, USA

The brakes at a low rate of speed (1-10 mph) partially gives out which prolongs the stopping distance of the vehicle. It seems as though the ABS kicks in but for no reason. Must strongly push down on the pedal to get vehicle to stop, which still requires additional stopping distance. Has occurred sporadically from mid-2018 to March 2019. No resolution through dealership.

- West Point, NY, USA