10.0

really awful
Crashes / Fires:
13 / 2
Injuries / Deaths:
2 / 0
Average Mileage:
46,092 miles

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« Read the previous 20 complaints

problem #122

Jul 012019

Sierra 1500

  • 57,000 miles
I only have 57,000 miles on my truck, which is why I am reporting this. The truck turns off completely. I have been going to make a right/left turn and the truck shuts down completely. I have no power steering and limited brakes. This has happened to me twice now. I am lucky enough that I am strong enough to turn the truck without power steering otherwise I would have hit vehicles both times this happened. There has to be some type of electrical flaw that is making this happen. I want to get this resolved before my insurance company has to get involved because I am in a car accident. If this is something the manufacturer takes care of that would be great, otherwise I would just like to know if someone else has had this issue and has found the resolution.

- Paradise Valley, AZ, USA

problem #121

Jan 012019

Sierra 1500

  • 65,000 miles
When the truck's vacuum pump fails, the brake pedal becomes very hard to push. The truck does not stop at low speed when this happens. The first time this happened, I was backing into a parking space at christmas tree stand. I nearly backed into the tent and persons loading the christmas tree in the truck. The second time this happened, I was parking my truck in driveway. I rolled about 6' to 8' before stopping. I nearly hit my house. GM issues a "special warranty" but they refuse to cover the repairs because of the vehicle mileage. This same issue is well documented by other GM truck owners for 2014 to 2018 model years.

- Covington, LA, USA

problem #120

Apr 202016

Sierra 1500

  • 15,000 miles
Brakes do not work when in reverse or at low speeds. Problem was there the day I purchased the vehicle. A couple weeks after purchase I backed into vehicle in a parking lot. I was told it was "normal" after almost having a wreck I did some research. How is this not nationally advertised as a recall yet? this is a huge safety negligence on GMC's part. The vacuum pump is known to fail by every dealer I have called. Also everyone I know who has the same model truck also lives with this problem.

- Pearland, TX, USA

problem #119

Jun 302019

Sierra 1500

  • 69,100 miles
When coming to a stop the brake pedal gets hard to depress and the rate of deceleration chages makes it hard to jusge when and where the vehicle will end up.

- Braintree, VT, USA

problem #118

Jun 252019

Sierra 1500

  • 88,000 miles
While in a drive through I was creeping up and when trying to come to a stop my brake pedal would not depress all the way as normal and took a longer than normal time to stop even with both feet pushing on the brake pedal. I ended up rolling into the car in front of me. I took the car to the dealership the next day and was told that my vacuum pump/brake booster needed to be replaced.

- Smyrna, GA, USA

problem #117

Jun 242019

Sierra 1500

  • 68,000 miles
When you step on the brakes in motion the brake pedal is hard and vehicle takes longer to stop.

- Thomasville, GA, USA

problem #116

Jun 162019

Sierra 1500

  • 102,000 miles
The brakes periodically do not work at low speeds. The brake pedal gets hard to push to the point you have to stand on the brakes to get the vehicle to stop. I haven't gotten in an accident yet but it's been very close twice now where I've almost hit a car in front of me at a stop sign.

- Walkerton, IN, USA

problem #115

May 302019

Sierra 1500

  • 60,000 miles
Hard brake pedal at low speeds especially while towing or traveling on inclines. Brake pedal becomes hard to decompress without warning and vehicle is unable to be stopped.

- Brunswick, OH, USA

problem #114

Jun 122019

Sierra 1500

  • 72,500 miles
My 2015 GMC Sierra failed to stop at low speeds today. I avoided the collision by pulling off the side of the road. The peddle was extremely hard to push. I received a notice by GMC that its the vaccum pump and they will only cover the warranty up to 72K miles. My truck has 72,560 miles.

- Corona, CA, USA

problem #113

May 242019

Sierra 1500

  • 88,429 miles
Brake vacuum pump: While attempting to stop, the brake pedal became very firm and the vehicle was difficult to stop. The vehicle continued to move while depressing the brake pedal and required a substantial amount of effort to make the vehicle come to a stop. It was intermittent, but it did occur several times on the day I first noticed it and was often at low speed. Fortunately I was not involved in any accident when this first occurred. I was able to drive it to the nearest dealership immediately and had it repaired that day. The dealer was able to duplicate the issue and determined the vacuum pump to be defective and required to be replaced. Once replacing the vacuum pump, the brakes performed as expected. Attached is a copy of my invoice with the dealer narrative describing the repair.

- Lake Orion, MI, USA

problem #112

May 132019

Sierra 1500

  • 75,000 miles
Low speed brakes hard and takes time to slow and stop. Brakes seized backing down driveway 2xs. Got notification from GMC that they are aware the vacuum /power my be defective and if you experience this problem the dealership would fix it at no cost but ot had to have less then 72,00 miles. Drop it off at our dealership and they claim no problems found. They had for 3 days and just drove it around with a computer hooked up to it. Said no codes came up so they are not bothering with it. Pick it and still the same. Husband went back. They don't want to bother cuz the milage is over 72,000. We have 75,000. I am afraid to drive it. They need to be recalled for the vacuum /power brake issue. Our truck is only 4 yrs old and we paid big money for it. We live Chevy/GMC. We would never own anything else. Recalk is needed.

- Monson, MA, USA

problem #111

May 162019

Sierra 1500

  • 57,000 miles
After coming to a stop or reaching slow speed, the brake pedal becomes firmer with each pump until the pedal only moves roughly an inch before stopping, and braking force is barely enough to keep the truck from idling forward. When this happens on a downward slope at a stoplight it requires massive amount of force on the brake pedal to keep the truck from rolling into the car in front of it. Also, if traffic begins to move after a stop and then stops again abruptly without gaining much speed, the same thing will occur and it is extremely difficult to not hit the rear end of the car in front. After doing some research this seems to be a common issue with the vacuum pump. I will be visiting a dealer soon. 2015 GMC Sierra slt with 57,000 miles.

- South Bend, IN, USA

problem #110

May 102019

Sierra 1500

  • 38,240 miles
I after pulling into a service station, I was backing up and suddenly had no brakes. I almost hit another vehicle.

- Atwater, CA, USA

problem #109

May 012019

Sierra 1500

  • 93,000 miles
Hard to no braking at low speed. Power brake assist failure.

- Troy, MI, USA

problem #108

Apr 302019

Sierra 1500

  • 30,000 miles
Increased / inconsistent brake pedal effort at low speeds; truck takes more effort to stop, increased breaking distance

- Hiram, GA, USA

problem #107

Jul 012018

Sierra 1500

  • 35,000 miles
Brake pedal becomes hard and non efective when attempting to park or at low idle speeds on numerous occasions nearly causing serious harm to bystanders and property. This is a major problem with GM trucks and do not know why a recall has not been issued to protect the public from serious injury.

- Greenville, NY, USA

problem #106

May 012019

Sierra 1500

  • 66,000 miles
Brake failure at parking lot speed. While reversing in truck, brakes became hard and failed. Almost hit another vehicle.

- Pottersville, MO, USA

problem #105

Oct 012018

Sierra 1500

  • 53,000 miles
Hard pedal, extremely poor braking response while slowing and during parking of vehicle, especially when multiple pedal pumps are required. Progressively worsening over past 6 months. I replaced vacuum boost pump and problem was corrected.

- Hillsboro, VA, USA

problem #104

Apr 252019

Sierra 1500

  • 82,000 miles
At low idle the braking become very stiff and extreme pressure on the brake peddle is need to stop the vehicle. Hank graff of durand mi indicated it is due to a failed brake assist vacuum pump. The service rep. Also experienced the issue when they pulled the vehicle into the repair bay. As the owner, I have experienced this braking issue multiple times.

- New Lothrop, MI, USA

problem #103

Apr 212019

Sierra 1500

  • 102,000 miles
The contact owns a 2015 GMC Sierra 1500. While driving 50 mph, the brakes failed to respond and the contact lost control of the vehicle. The contact drove on the shoulder and was able to park in a rest area to inspect the vehicle. The contact drove the vehicle back home. The vehicle was taken to mcgovern Buick GMC (located at 2806, 150 turnpike rd, westborough, MA 01581, (508) 439-4362) where it was diagnosed that the vacuum brake pump needed to be replaced. The vehicle was not repaired. The manufacturer was not aware of the failure. The failure mileage was 102,000. The VIN was unknown.

- Somerville, MA, USA

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