Vacuum pump is in the shop now being replaced for the 7th time in almost 6 years. The previous one was replaced in September 2023. You get no warning signs, then all of a sudden you can barely press down on the brake pedal. This started within the 1st year of purchase.

- Canton, MS, USA

I was driving down the highway between 65 and 70 MPH. The semi-truck in front of me almost missed his turn and stopped quickly to make a 90 degree turn off the highway. I went to slow my vehicle appropriately, and my brakes did not respond. I had no warning that my brakes were compromised. I quickly used the downshift button to use my engine to slow me down and I crashed my vehicle off the road into the sagebrush (luckily no trees and there wasn't a dramatic drop off). At that time, after my vehicle came to a stop, I received a warning on my dash that stated "service brake assist". I looked up the issue on my phone to see what may have happened, and read that GMC had a recall for this very issue. I contacted the dealership and they indicated that they were aware that the 2018 GMC Terrain has this issue, but it was not included in the recall. I am traumatized by this incident. I am a very experienced driver, but I had bought this vehicle for my daughter, had she been driving, this would have been a catastrophic accident. I have nightmares about if this had failed when approaching a crosswalk or in a school zone. If GMC is aware of the problem, and they had a full recall on this on other models with this same problem, why aren't they fixing the Terrain, why are they waiting for a fatality. It is unacceptable, dangerous, and I don't even want to know what the cost is going to be to repair the vehicle. I am thankful it wasn't much worse.

- Reno, NV, USA

Safety was put at risk when brakes went out without warning, and unable to use emergency brake at that time. Car was serviced for over $1700, with the mechanics stating that the piece -??blew up.-??

- Olathe, KS, USA

The brakes stop working, they get really stiff and locks in the middle of the highway, very hard to stop and almost caused an accident, it is not the first time, the vehicle was serviced by an authorized mechanic and the problem had been resolved until today, the brakes locked and almost caused me to loose control of the vehicles brake system.

- San Antonio, TX, USA

We were driving back from vacation and while on I-95 the brakes went out. The check engine light came on and the service brake assist light came on. My husband was able to pull off to the side of the road but if it weren-??t for already starting to slow down due to an accident we were approaching this could have been much worse. When the brakes went out my husband could hardly press the brake peddle. After researching this appears to be a known issue amongst GM vehicles. It appears to be the vacuum pump that went out. There is an open recall for certain models of GM but not all. This was such a dangerous situation. We literally could have died. This should be a recall for all models as Terrains appear to be largely affected as well from this issue.

- Ocala, FL, USA

While driving on the interstate the brakes all the sudden stopped working. I was able to stop the vehicle by pulling over to the shoulder of the road. I received a warning saying service brake assist and a check engine light after the brakes went out. The vehicle later shut off and is no start with no warning codes. I am currently towing the vehicle to a mechanic. Several people claim to have the same issue online stating that it is an issue with the brake vacuum booster shearing off in the exhaust cam which then causes major damage to the engine. It appears the same issue exists with several other GMC models that were already recalled

- Ocala, FL, USA

While driving truck around 55mph with family in vehicle and tried to make a stop in a traffic light, notice truck had a hard brake pedal and did not stop, luckily I (Parent) around [XXX] of age was able to divert around and put on neutral until truck stoped in side of road. After a while of looking around and checking truck for system errors or lights there was no indication not warnings. i was able to move truck to a near by location and asked a mechanic to go look at it. Mechanic notice oil coming out of brake vacuum pump and took out part and mentioned that the pump had broken in pieces inside engine block and might need a replacement. Truck is still on shop and waiting for our decision to fix. At this point my family is so scared of this truck and don't even want to talk about the incident. Me as a parent is very concern on all this new vehicles that are suppose to be more reliable and better protection than older vehicles, i feel more protected in my 90-??s truck. I hope this gets enough attention to at least save someone's life. Thanks in advance, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Rio Grande City, TX, USA

Vacuum pump failure which leads to total engine repair

- Ward, AR, USA

I was driving and my brakes seized up. Could not apply pressure at all. This could have caused serious injury to myself and my daughter as we were driving alone 3 hours from home. I was able to get into a parking lot but now my car won't start.

- Benton, AR, USA

My vehicle keeps showing -??service brake assist-?? and -??service TSC-?? lights. I was on a hill and the auto-start was engaged, as well as hill assist. When I let off the brake pedal slightly to get the car to come out of auto-start, the car acted like it completely shut off (radio went black and lost power) and the car just started rolling backwards quickly. If there was a vehicle behind me it would-??ve %100 caused an accident. My wife and child ride in this car every day and this is the second time I-??ve had serious issues with this car. The first time I was driving down the interstate and the brake vaccuum pump went out and I lost all brakes, I had to put all 180lbs of my weight on the brake pedal to get it to stop.

- Cleveland, TN, USA

Vehicle brakes went completely hard and vehicle would not stop. There was no warning signs, no lights on the dash and vehicle was driving on highway normally. Upon taking a highway exit, I could not stop the vehicle, completely unexpectedly. Upon further research it is a very common problem that needs to be addressed. My 3 kids and wife were in the vehicle when it happened, and this is actually the second time it has happened. The first time it happened we could not stop the vehicle at all to turn onto the road I live on, could barely push the brake pedal and coast to a stop. The repair last time it happened was the camshaft driven brake booster vacuum pump, and it has failed again after 20,000 miles. This is a serious manufacturer defect that has almost killed my family twice now.

- Epsom, NH, USA

While driving down the road at approximately 55 mph, came up to an intersection, 4 Lane I was in the right lane to go straight, there was a right turn lane next to me. I applied the brakes, pedal was really stiff and very slow to respond, I was able to edge over into the turn lane cutting people off and just barely missing the vehicles in front of me. It took 5 car lengths to stop my vehicle. When I finally was able to get the vehicle fully stopped I was almost in the paths of the crossing traffic.. when the light turned green I was able to slowly cross the intersection looking for a safe place to pull over. Immediately crossing the intersection the Service Brake Assist notification appeared, about another half mile the vehicle informed me of loss of power and that it was reducing engine power (limp mode). I was able to find a gas station parking lot to put it. When I opened the hood I noticed quite a bit of engine oil located under where the brake assist pump was located. I had lost about 1.5 quarts of oil. I refilled that. The next day I returned with a tow dolly. The vehicle was started just long enough to load and unload it at home. We pulled the vacuum pump where upon inspection it was noticed that the part has exploded and so far we are still missing some pieces that may be inside the engine. This is a known and documented problem of this part and should have a safety recall issued.. I still owe over twenty eight thousand on this vehicle and it has only 109,000 miles on it. I hope we can find all the pieces and that the engine wasn't fately harmed. GMC needs to make this right, a lot of people could have been harmed.

- Rockmart, GA, USA

The contact owns a 2018 GMC Terrain. The contact stated that while driving at approximately 35 MPH going over a hill, the brake pedal was depressed but was firm and failed to depress as needed. The engine power reduced message was displayed and flashed on and then off. The brake assist warning light was illuminated. The service transmission message was displayed. The contact continued to depress the brake pedal until the vehicle responded as needed. The driver was able to pull into a parking lot, and the vehicle rolled to a stop. While driving, the engine misfired. Additionally, the vehicle failed to fully shutoff. The vehicle was towed to the local dealer, where it was diagnosed that the brakes had locked up and that the vacuum pump needed to be replaced. The contact was also informed that the cam shaft had fractured inside the engine. Additionally, the fuel injector, fuel line, and fuel pump needed to be replaced. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 19V645000 (Service Brakes, Hydraulic) and 23V013000 (Fuel System, Gasoline). The manufacturer was contacted, and the contact was informed that the VIN was under recall. The failure mileage was approximately 30,000.

- Chicago, IL, USA

On 9/3/23 I was travelling down interstate 94 in Illinois when all of a sudden my check engine light came on. Not knowing what the issue was, but knowing that the car still seemed to be OK and I was only a few miles from home I decided to drive home and figure out the issue from there. At this point I had no idea that the brakes had completely locked up. Once I realized what was happening I did my best to slow the vehicle down by decelerating, frantically pumping on the locked up brakes, and then finally slowing enough to take an exit and roll in to a gas station. Frankly, it was the most terrifying moment of my life travelling 70 MPH without the ability to stop. Upon inspection, the independent service tech informed us that the vacuum pump had exploded (yes, exploded) and that he had never seen anything like it, especially in a car with less than 70,000 miles. What component or system failed or malfunctioned, and is it available for inspection upon request" The vacuum pump failed and unfortunately it completely exploded so there were only a few pieces left inside of the engine. How was your safety or the safety of others put at risk? My brakes locked up completely on the interstate, with my family in the car, and I was unable to stop. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. The independent service center where I currently have the vehicle has confirmed, and spoken with GM. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? No, GMC refuses to do anything about it even though there is a prior recall for the same part on other GMC vehicles during the same time frame. I'm told it's the exact same part. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear" Yes, roughly 1 minute prior to the breaks locking up the "check engine" light came on.

- Gurnee, IL, USA

Driving on highway and all of a sudden I could not break - the car breaks failed to operate - had to slowdown by it self and pull to a McDonalds, I had the loss of effective braking with no warning whatsoever. We found out that the Break Booster Pump was destroyed without any warning from the electronics of the SUV.

- Mahwah, NJ, USA

Last year this time brakes went out at 50 mph power brake module imploded from inside out. The part was on national back order. Second incident car stopped immediately while traveling 40 mph no warnings or anything both incidents could of been horrible. Not sure on second incident the issue yet car is in shop. Both incidents are safety concerns for myself and others. Driving at average speeds and something malfunctioning is a great concern of mine. I contacted GMC no one to talk too just chat and the person on the other side told me it was no concern of theirs all was dumbfounded by the conversation but until I said I was putting on social media and bringing to everyone attention her entire tune changed in regards to part and service. So I researched locally and luckily I found the part they had one left and I was told by dealer that it is an issue on these vehicles. Both safety incidents have been within a year of each other 2022 and 2023

- Georgetown, OH, USA

The vacuum pump started leaking and the car was parked immediately. When The pump was pulled out to be replaced, the reason for the leak was identified. The vacuum pump had busted into small pieces which are now in the engine.

- Point Pleasant , WV, USA

The contact owns a 2018 GMC Terrain. The contact stated while driving 45 MPH, the check engine warning light illuminated. The contact stated while making a left turn the brake pedal was depressed but failed to stop the vehicle. The contact was able to continue driving without proper braking response to her residence. The contact stated she used the parking brake to fully stop the vehicle. The contact's husband took the vehicle to the local dealer, where it was diagnosed with needing an unknown pipe and vacuum pump to be replaced. The vehicle was not repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 79,000.

- Oswego, IL, USA

Driving home from our local town 4/15/2023, the brake pedal became to hard to push down. Check engine light came on as I got to my driveway, and that is 1 mile from the main road. My kids were scared to tears as was my girlfriend. Run a scan and dtc p0557. Come to find the vacuum pump on the top drivers side of motor is the part that is bad it broke inside the valve cover. Looking up the issue and find out it is a known problem and no recall. I have kept the parts and all receipts for the repairs, I have to do myself cause the repairs are way to much for me to pay out of pocket. This is a serious issue for this car and year and GMC needs to address the issue. Why has nothing been done yet"?? I am making payments on this car with no warranty for the car so I'm stuck fixing the car. But GMC knows that this is a problem and does nothing?!? I remember when American cars were good cars what happened to that time ?? And what happened to company's being responsible for the product they put out to customers" Guess that time is gone, I won't buy another American car again, unless it's a old Detroit built car.

- Barstow , CA, USA

I was coming to a stop with my vehicle and the brakes would not work. I carefully got my car home and to a shop. It was determined that the break booster pump broke which caused metal parts to go into the engine. Now my engine is blown! Bought my car brand new in 2018 and kept up with regular vehicle maintenance has 90k miles.

- Lima, NY, USA