Loss of power brakes when creeping and applying brakes several times in a short time. Tested and changed vacuum pump.

- Menasha, WI, USA

The contact owns a 2015 GMC Sierra 1500. While driving at low speeds or when the gear selector was in reverse, the brake pedal traveled to the floorboard. The contact mentioned that the failure occurred periodically. The vehicle was taken to everett Buick GMC (21115 I-30 frontage rd, bryant, ar 72022, (501) 303-4393) to be diagnosed, but no failure was found. The dealer stated that the brakes were "perfect". the vehicle was not repaired. The manufacturer was made aware of the failure. The VIN was not provided. The failure mileage was 45,000.

- Sherwood, AR, USA

I was driving down a hill at about 15 miles an hour and when I went to press the brake pedal I heard a noise and the brake pedal went to the floor and truck would not stop. I had to swerve off the road to avoid a collision. After, the brake pressure returned while driving, but when stopped it would lose pedal feel and go back to the floor. After reading articles it was obvious the vacuum pump was failing. I limped the truck home and took it to the dealership and am waiting to hear back.

- Lancaster, CA, USA

There is a known brake problem caused by faulty vacuum pump. With the vacuum pump failing there will be loss of assisted braking. Some people have noted requiring 2 feet to stomp on the brakes to stop the truck. The dangerous braking problem seems to happen during low speeds. Some members on the forums have mentioned getting into accidents. GMC does not cover the vacuum pump under their warranty which is ridiculous. I have listed some forum threads as proof of not just me having this issue. Https://www.silveradosierra.com/ecotec3-5-3L-V8/brake-booster-vacuum-pump-failure-T686609.html https://www.silveradosierra.com/brakes/rock-hard-brake-pedal-2014-low-speed-T595097.html https://www.GM-trucks.com/forums/topic/204871-vacuum-pump-going-out/ https://fox6now.com/2018/11/23/GM-under-investigation-for-faulty-brake-vacuum-pumps/ even the government is investigating.

- San Francisco, CA, USA

It started happening a week or so ago where when in reverse or after switching from reverse to drive and trying to brake the pedal wouldn't compress, it was as if they were locking up on me. I would have to put most of my body weight on the pedal to even get the truck to stop, to the point where I almost ran into my neighbors car backing out of the driveway. It seemed to mainly happen at slower speeds, in both drive and reverse as it happened on more than one occurrence. Luckily I decided to take it to the GMC dealer before anything serious happened, but this is a huge safety concern and I feel it needs to be addressed. The dealer also knew exactly what the issue was before I could give them any information, so it seems like this is a common problem. They replaced my vacuum pump and we will see if that fixes the problem.

- San Angelo, TX, USA

Brake pump went out almost ran into a pole. Reading online and see a lot of people having the same problem. Angry!!

- Miami, FL, USA

I was pulling a travel trailer at 55 miles an hour, I came over a hill to an intersection and I had lost my brakes. I managed to finally come to a stop. I disconnected my trailer. I went to a local GMC dealership, and they did not have time to repair my vehicle. I took it to an independent repair shop, and they said my vacuum brake booster pump had failed. They installed a new vacuum breaker booster pump for the next day. This was a very dangerous situation, as I lost 95% of my breaking power while pulling my travel trailer.

- Union Grove, WI, USA

While driving at slow speeds, the brake pedal became very hard to push. This caused the truck to be difficult to stop, which caused me to almost rear-end the vehicle in front of me. This has happened several times. In response to this, the GMC dealer replaced the vacuum pump.

- Ludington, MI, USA

When backing up, after repeatedly pressing the brake pedal, the brake pedal went to the floor and would not stop the truck. The truck rolled uncontrollably down the driveway and luckily did not hit anyone or anything. It could have killed someone though. The same issue occurred in a parking lot when backing up in an open space. After repeated hitting the brake pedal to line up the vehicle, the brakes stopped working an I could no longer stop the truck.

- Grand Rapids, MI, USA

The contact owns a 2015 GMC Sierra 1500. While driving 15-25 mph, the brake pedal was depressed, but was difficult to slow down or stop the vehicle efficiently. The contact stated that the brake pedal was very stiff. The vehicle was taken to kunes country Chevrolet Buick GMC of elkhorn (located at 1350 wi-67, elkhorn, wi 53121, (262) 725-4068) where it was diagnosed that the vacuum pump was weak. The vehicle was repaired. The manufacturer was not contacted. The approximate failure mileage was 68,800. Consumer stated vehicle was repaired.

- Big Bend, WI, USA

I pulled into a parking spot and lost the ability to stop my truck. The brakes locked up and I couldn't push down on the brake pedal hard enough to get the truck to stop. I was going slow enough to use the curb in the spot for it to stop me from hitting anything. I had my car towed to a repair shop and they confirmed that the brake vacuum pump failed and had to be replaced along with the master cylinder and because the vacuum pump was the initial point of failure, the repair was not covered under my warranty. Vehicle repaired

- Conroe, TX, USA

The contact owns a 2015 GMC Sierra 1500. While driving 25 mph, the contact heard a grinding noise emerging from the front driver side of the vehicle. The vehicle was taken to hennessy Buick GMC (7261 jonesboro rd, morrow, ga 30260) where it was diagnosed that the brake vacuum pump needed replacement. The manufacturer was notified of the failure and provided case number: 8-4881978797. The vehicle was repaired. The approximate failure mileage was 102,000.

- College Park, GA, USA

I first noticed the problem when I was backing down the ramp to launch my boat. Generally I can lightly touch the brakes and the truck will stop immediately. But this time it did not and I had to pump my brakes multiple times before it finally came to a stop. I was quit alarmed but kinda blew it off. The truck had traveled about six feet further than I had anticipated. About a week later I stopped to go through my gate at my farm and when I drove through the gate which is on a slight hill decline it happened again. I went to touch the brakes to stop and ended up pumping the brakes violently in order to get the truck to stop. This time I traveled about seven or eight feet before coming to a full stop. After this incident I was convinced to take it to the dealership. It occurred once more during that time. The dealership said it was a malfunction in the vacuum pump that works off of the main engine and oil from the engine had contaminated the braking system. I had to have replaced a pump, booster, cylinder, pipe, and fluid for a total of $1266.33 dollars. That invoice number is 208452. I feel this is a serious safety issue when you think your vehicle is going to stop and it does not. This can cause a panic situation!

- Hammond, LA, USA

On November 17th 2018 my brakes went out on a 2015 GMC 1500 at 35 mph stopping at a red light which just turned green.I switched lanes and almost crashed. I had my grandchildren in the vehicle along with my wife. The vehicle need to be towed to a GMC dealer. The diagnoses was the vacuum pump total failure the brake pedal was hard with no stopping power. My GMC had 34000 miles on it. Now I have a tow bill and repair cost for a part GM will not recall. This was reported to GM and they opened a case and closed it. The said they would give a hundred dollar coupon. This is ridiculous some one is going to get killed because of this faulty part. I thought they would be will to help and make things right. GM case 8-4845403712 thanks this corporation needs to be responsible.

- Slidell, LA, USA

The contact owns a 2015 GMC Sierra 1500. While driving 5 mph, the brakes seized. While driving over 5 mph, the brakes performed normally. The vehicle was taken to baglier Buick GMC (248 pittsburg rd, butler, pa 16001, 742-602-4676) where it was diagnosed that the vacuum pump fractured. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 49,000. The VIN was unknown.

- East Brady, PA, USA

When driving forward or backwards at low speed brake pedal seems like it locks up and it is extremely hard to stop the vehicle I had to press the parking brake a couple times just to get it to stop

- Tracy, CA, USA

Experienced an unusual reaction to breaking. A few days later I had brake warning lights on the dash. Took the vehicle to the dealer and they had to replace the cylinder brake master and the brake booster and add new fluid. Which I paid for. Now I see there may be other issues as there are other complaints you're investigating. I want to put mine on record.

- Bellaire, MI, USA

Brake system failure. Brake pedal would depress to the floor and stop working as the truck was slowing down. This would happen in all braking situations. I took the truck to the dealership and they stated the vacuum pump failed. $1142.67 for repair! Nov 15/ 2018.

- Whitewright, TX, USA

I bought this truck in Dec.2017 sense March/ April of 2018 I have experienced at least 8 times maybe more and just last week. The brake pedal had lost it's power assist. This seems to happen in very close slow speed traffic or in parking lots when parking. The way I solve this problem is to put truck in neutral and increase RPM's or you 2 feet on the brake pedal ithe power assist will soon return, these situation could be a real problem at higher speeds. I have checked the vacuum booster for leaks, brake fluil and done a front and rear brake job. The week of Nov. 18 I saw an article in the boston globe about this specific problem and under investigation. I contacted my local dealer central Buick and GMC in norwood MA..on Nov 26.2018 the service writer said he knew nothing about this problem or complaints nor the ongoing investigations. His thought was bring the truck in and we will check and repair at my expense. Sadly I wish his response was different. Thankyou D.S.M.

- Medfield, MA, USA

At slow speed backing up or moving forward, I lose power assist for braking, having to almost stand on the brakes to stop. This happens intermittently. Street or parking lot.

- Port Allen, LA, USA