2019 GMC TERRAIN Service Brakes Problems

52 complaints about Service Brakes

52
Complaints
1
Crashes
0
Fires
0
Deaths

High Severity Issue

This component has been associated with crashes, fires, or deaths.

This Problem Across All Years

All Service Brakes Complaints (52)

Dec 16, 2025

Failure of the cam driven vacuum pump causing brake failure. Leading to a hard brake pedal which increases risk of a crash. Debris from the broken vacuum pump can fall down into the engine causing a catastrophic failure of the engine needing a replacement. This happens with little to no warning. Warranty companies will not pay to repair the known issue. A recall needs to be issued for this to provide a fix. This is a family suv and I do not feel safe putting my children in a vehicle that can endanger their lives and safety.

Oct 21, 2025

When approaching a stop sign, the brake pedal became extremely hard I was unable to stop, and rolled through the intersection avoiding collision. I was able to slow down enough to engage the emergency brake. There are no lights on the dash.

Oct 12, 2025

Driving approximately 70mph on interstate. Came to a slight hill, gently applied brake pressure, brakes become hard to apply/would not apply. After diagnostics, found Brake Vacuum Pump with damaged fins.

Oct 6, 2025

We have been having varying issues with this GMC, and have found numerous others with the same issue. Vacuum pump went out while driving. Thankfully I was not going very fast and it stopped prior to hitting someone. This is a known issue, yet no recall from GMC. Vacuum pump is said to have been failing causing other engine and transmission issues that can never be "re-created" for the vehicle to be fixed.

Oct 4, 2025

I was backing out of the driveway, and it was extremely hard to brake enough to stop the car. I immediately parked back into the driveway. I had to stand on the brake to completely stop. Vacuum pump was completely busted and in many pieces.

Sep 10, 2025

While working out of town for work my engine light started flashing and the dash lights went nuts. My brakes were nonexistent and were hard as a rock. I had zero warning as to what happened. Working 3 hours away from home the car had to be towed and I was informed the engine code came back as my cam shaft. Took it to the dealer as Gm has a bulletin put out. I didn’t know what that meant. Long story short and 3000.00 dollars later I find out that the vacuum pump exploded which cause the cam shaft to fail. I was out of work for almost a month. There is a recall for almost all vehicles from this year but not the 2019 terrain even though it contains the same vacuum pump as all the recalled makes and models. Vacuum pump, cam shaft, oil pan, oil pump had to all be replaced at under 100,000 highway miles. Someone needs to address this problem.

Sep 7, 2025

Two weeks ago I was driving on the highway. My car felt fine. No warning light the dashboard. Suddenly I receive a notification on my dash stating “engine speed reduced” and my check engine light went on. My car at this point still feels fine, not shaking, no smoke, etc. I’m on the highway and not in a safe position to pull over. 2 minutes later I receive another notification on my dash stating “service breaks”. I immediately tap my brakes to check and they are stiff. I let off the gas as I was approaching the exit and begin pumping my brakes. They continue to be stiff. Luckily there was no one I front of me as this exit led to a rotary. I was able to coast around the rotary and into a parking lot where I attempted to push the E- break which did not work. My steering tightened and then my car died. I have the car towed to GMC where I bought the vehicle. Am told I will be charged a diagnostic fee and they will let me know what they find before repairs are made. I receive a call back the following day stating “the vacuum pump exploded causing you to loose brakes”. I was told “the vacuum pump and repairs would be about $1,200. BUT they could not guarantee that once the vacuum pump was removed, there wouldn’t be more debris and destruction to the cam shaft and engine”. We asked they continue with the diagnostics and check the engine for debris. We receive a call back stating “the vacuum pump exploded and there are shards of medal debris in your engine”. Recommendations are that I need a new engine as "the vacuum pump explosion caused catastrophic damage to the engine". My safety and the safety of other innocent drivers on the highway were put in extreme danger! I lost all break control, power steering, and emergency break control. I had minutes from the time the first warning alerted to the time I lost complete control of the car. This is a known issue with GM Motors specifically made between 2016-2019.

Aug 31, 2025

While driving the vehicle the car went into limp mode and the back brakes stopped working. The car had to be drifted into a parking lot. The vacuum pump malfunctioned and has damaged the engine. If it was me in the driver seat instead of my partner, the incident would’ve 100% been an accident. The car was really unable to be controlled and we just happened to have that space that was empty to turn into. The car gave code when this happened. When getting a tow the car also wouldn’t take itself out of park or start to go into neutral to move the car to get it towed. Nothing is working with each other anymore and we were on a busy road of people when our brakes just went out.

Aug 15, 2025

Brake vacuum pump premature failure. As you see GMC, terrains, in Equinox, I have an issue, while the engine it's on while driving etc, if this bark fails, you will have an issue I'm trying to stop. This is a known problem or GM. And as of now, they have not come out with a solution or a recall for this problem. This problem has caused many customers. To lose thousands of dollars, he repairs. I'm not covered by the warranty. This should be addressed and repaired as soon as possible as it may cause someone else to lose their life. Second problem is the 9 speed transmission transmission lack power when trying to gain speed as you enter the highway. Lastly they blamed the selenoids etc. Lastly the pulley belt retention broke down premature with only 68k miles. This is an ongoing problem gm is well aware and tries to hide or fix. When someone buys a vehicle we expect to last longer than 100k miles.

Jul 28, 2025

Friday July 25, 2025 I was driving my 2019 GMC Terrain SLE and when exiting the interstate the brake pedal got hard and I could not stop. After almost rear ending another vehicle, I got the vehicle into the ditch and safely off the road. After several attempts to correct the problem, I was unsuccessful. The vehicle was towed home and seen by a mechanic. The vacuum pump went out while I was driving.

Jul 8, 2025

Accelerating from a stopped position into a busy intersection heard a loud clunk come from engine bay resulting in immediate "Reduced engine power" warning and stall condition. Was able to push vehicle onto the side of the road. Engine would not restart and a tow truck was called. Vehicle towed to local dealership who discovered that Vacuum Pump had failed resulting in sheering off of the exhaust camshaft. Dealers recommended fix was to replace vacuum pump and camshaft at around $4,000 but could not guarantee no debris had gotten into valve body resulting in engine failure so stated they could replace with used engine for 8500. Second vacuum pump to blow on this vehicle, first at 35k miles and replaced under warranty, this incident at just under 80k miles. Could not afford repairs and vehicle has sat for nearly 2.5 years. Contacted GM many times over that time period to get no assistance, only the offer of a small discount on a new vehicle. This incident could have proven fatal if happening at highway speeds since it stalls engine out and makes braking nearly impossible. Both GM and the NHSTA have really flunked on this one, should have been recalled during first complaints in 2020. I will continue to file complaints here on NHSTA and with GM until the cows come home.

May 18, 2025

Vacuum pump broke and car has no brakes

May 12, 2025

While driving the breaks completely locked up and the smell of exhaust entered through vents. Ran a code machine indicating that the break booster power vacuum pump was needing replaced. There are no other issues with my vehicle that would cause it to malfunction out of no where.

Apr 27, 2025

Breaks went out on vehicle with no warning or lights on dash. Nothing prior or now indicating any issues with breaking system.

Mar 2, 2025

Vacuum pump failed causing hard brake pedal and the inability to properly stop the vehicle. Thankfully I made it to a safe area and had the vehicle towed. No warning light or engine service lights ever illuminated. Once it was taken apart the bearings were disintegrated and metal shavings are in engine components.

Feb 4, 2025

Service parking brake comes on, steering reduced. Problem reoccurring often, but intermittently. Actuators malfunctioning causing many sensors to fail off and on. Huge safety concern for myself, my riders, and anyone else on the road. When this happens my car has to “think” to move unless you clear the pop up message. Check engine light comes off and on at its leisure. When steering reduced comes on the car will not move until ready. This is clearly affecting electrical things as when I shut power off to other supplies it sometimes becomes more frequent as well as less frequent. The car does not understand what to do as its computers are confused at what the problem is, as the problem does not consistently happen. I have print outs of one time I caught it with failing actuators. I refuse to go to the dealership as I’m told “oh the problem isn’t happening now.” Which negates safety of all people on the roadways. You’re more than welcome to inspect. Though I will be present as I refuse to be told there’s no problem. As previously stated this happens when it wants to happen, but again I’ve caught the issue and can supply information.

Jan 16, 2025

Driving home from dropping my daughter off at school. When slowing down at stop sign, car locked up brakes completely, almost went through stop sign, car shut down engine and placed vehicle in park. Diagnosis is a vacuum pump failure, causing reluctor wheel to spin freely from camshaft. This happened without warning at 70k miles. Diagnostic report from three weeks prior showed no bad diagnostics with engine or drivetrain components, or brake components. Had to have car towed from intersection where i was impeding traffic due to sudden failure. Garage is concerned regarding potential for debris and engine damage, as well as timing issues due to sudden failure of vacuum pump. GM has authorized vacuum pump recalls on other makes from prior years, not Terrain for some reason. This is how becoming highly reported failure among GMC/Chevy vehicles with shaft driven vacuum pump design between 2019-2022. GM has stopped using this design on 23 and newer models. They should absolutely recall these older models for this issue. Sudden vacuum pump failure can lead to unrepairable engine damage due to design.

Dec 9, 2024

My ESC randomly comes on. Service parking brake message comes on intermittently. Messages pop a up saying steering wheel assist limited, drive with care. Again, all of these are intermittent but when they happen my steering wheel locks up. Even mid turn. Being intermittent it doesn’t always happen and weather seems to affect when it happens, or that’s a coincidence.

Nov 1, 2024

The brake vacuum pump failed. I am extremely fortunate this happened at a rest stop after being on interstate 80 for numerous miles. Had this happened at highway speeds it would have been catastrophic for myself and most likely others. I do not have the part. The problem was confirmed and the psrt was replaced by Mavis Discount Tire in Mountain Top, PA There were no warning lights, signs, or symptoms prior to the malfunction. It is my understanding that GM has recalled the part on other models, but did not include the Terrain in the recall. I believe it should be before someone is seriously injured.

Nov 1, 2024

At 86,000 miles information board on dashboard alerted “Service, Brake Assist” upon braking from coming off of interstate. Diagnosed to a failed cam shaft driven Vacuum pump for power brake booster, next to no braking power with little to no warning what so ever. Terrible design from GM. Near miss collision due to brake failure with no warning. This needs an immediate attention through the engineering department to create a redundancy within the system. Nearly caused a very bad accident with my [XXX] and [XXX] daughters in the vehicle while fiancé was coming to pick me up from being on the road as a OTR truck driver. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Oct 24, 2024

I was riding on the freeway when my brakes failed. i was not able to press down on my brakes with zero warning. I had to swerve to miss cars and pull on the shoulder of the freeway and my car still would not slow down. I finally got from 65 to 35 and pressed on my emergency brakes. I stopped the vehicle then my engine light came on and I got my car towed to the car shop where my car would not stop and suffered internal damage to my engine from the brakes and vacuum pump

Aug 19, 2024

Break booster pressure sensor and engine underbooster causes the car to slam on breaks or not break at all.

Aug 4, 2024

The brakes failed with zero warning while driving. Car only has 60,000 miles. Extremely dangerous and it looks like it has been reported and known issue! It needs to be recalled.

Jul 29, 2024

on two occasions the vacuum pump booster failed causing the vehicle to lose braking ability while traveling on a highway at highway speeds. The vehicles brake completely failed and were unable to be engaged. the part was initially replaced by the dealer at the owner's expense and then the same issue occurred only a few months later. the second occurrence cause additional damage to the camshaft and timing chain causing the vehicle to not even be able to start. The vehicle was inspected by the servicing dealer and found metal shavings in the oil as well as extensive damage to the engine.

Jun 28, 2024

My daughter was driving her 2019 GMC Terrain at 15 - 20mph when she suddenly lost her brakes. Fortunately she had just turned into a new housing development where the road ended into an empty field. This could have been catastrophic for her & other citizens on the road. The following morning she would have been heading to work on a highway with heavy traffic with a posted speed limit of 65mph. We towed the vehicle home & after some investigating I found a vacuum pump failure. This vacuum pump broke apart internally sending chunks & shards of metal into her valve train. This issue is mentioned several times in Terrain forums & someone needs to address this issue before it becomes a fatality.

Jun 21, 2024 Crash

The contact owned a 2019 GMC Terrain. The contact stated that while the wife was driving at approximately 60 MPH, the brake pedal was depressed and it felt stiff. The vehicle failed to decrease in speed and as a result, the driver merged to the shoulder of the road however another vehicle crashed into the front driver side of the vehicle. The driver was able to merge to the shoulder of the road where the road bumps were able to decrease the speed of the vehicle. The ABS warning light was illuminated. The driver, front passenger, and rear driver's side passenger all sustained headaches and received medical attention via an ambulance on the scene. No occupants in the second vehicle were reported injured. A police report was taken at the scene and the vehicle was towed away. The cause of the failure was not determined. The manufacturer and local dealer were not contacted. The failure mileage was 40,000.

Mileage: 40,000

Apr 22, 2024

Vaccumm pump failed and broke metal shavings off into engine resulting in “engine failure”. I was driving on the highway with my 6 year old child in back seat, car completely shut down and shot a “reduced engine power” message while on a busy on ramp heading onto highway. This created an extremely dangerous situation for myself and my child as many cars almost smashed into the vehicle. I’ve seen many other complaints of this happening, the same exact parts and issue happened to the Chevy Equinox which resulted in a recall but they have yet to recall the Terrain, which is having the exact same issue. I am a single mother, with 20k still on my loan. This mistake made by gmc has now costed me over 5,000$ out of pocket for something that is not my fault and completely out of my control. Even after all of the money poured into this repair, I still feel unsafe in my own vehicle as there is no guarantee this issue will not happen again. I’ve kept up on all oil changes and maintenance of my vehicle. The issue was confirmed by a GMC mechanic which cost 500$ out of pocket for diagnosis as well. I also had to spend 1000$ on a rental out of pocket because of this. I have seen many others complaints of the same issue happening to their GMC terrain and am appalled no recall has been discussed after the reaccuring issue. I should not be having to pay out of pocket for an issue GMC has yet to fix or issue a recall on. I had to miss days of work, and it really was a huge inconvenience. I do not feel safe in my own vehicle even after the repair, cause I have no guarantee this won’t just happen all over again.

Apr 13, 2024

I had just gotten off the highway and had gone less than a mile on a 35 mph road when the brakes acted like the antilock brakes came on for a brief second then the brake pedal became very hard to push. This resulted in me having a difficult time stopping the vehicle. The service brake light also came on.

Mar 29, 2024

While driving on 95, I lost all engine and power breaks with no warning. A message came up on my dash stating that I had lost engine power. Fortunately an exit was up ahead so I was able to get there and coast down the ramp. I attempted to make a right turn to get out of the way but ran out of momentum. Dealership stated my vacuum break pump failed and went into the cam shaft. They had to replace those and the solenoid actuator and value. They also conducted an oil change. I received it back yesterday, started the car today and the check engine light was on. They found more debris and replaced another point and said if the light comes on again it's the timing chains in the engine. I went out leave and the check engine light was on. They are now keeping it to repair the timing chains. I am fighting with GM to cover the expenses since I see this is an issue in previous models/years of GMC and Chevy vehicles.

Feb 20, 2024

Brakes got hard all of a sudden locked up, almost hit another car, front collision warning keeps going off and automatically hitting brakes with no one in front of me. I’ve read it could vacuum brake pump failure. Please recall this as many people have kids and could hurt them.

Dec 19, 2023

It began with showing "Service Brake Assist" for about 2 weeks + then on Dec 18th 2023 around 10:30 as my fiancé was stopped at a stoplight and all of sudden when the light turned green she attempted to continue forward as traffic started to move only to stall stalled out before any movement could be achieve the battery was reading severely depleted and the vehicle would not function at all she was stuck in Drive and could not put the vehicle in neutral or even park to even try to restart the vehicle, she could not even turn the steering wheel, roll down the windows, open the door, or anything. the only thing she was able to accomplish was opening the hood so an officer that had arrived at this time could give her a jump, The officer also proceeded to leave the negative cable on the battery terminal and disconnected the Positive cable from the battery terminal which would have indicated a bad starter or depleted battery when the positive cable had been removed, which was not the case. she continued to where her appointment was and that is where i met her and took over vehicle to transport it home, driving with hazards on. I arrived at the house with no incident. then at 4:45pm on the evening of 12/18/2023 while at the stoplight I had a similar issue occurred as i was going from a stationary position to a forward slowly accelerated speed gaining momentum where the vehicle wanted to stall out while i was stopped at a stoplight attempting to proceed forward. and then at around 10:20 pm while stopped at a stop sign a similar issue occurred as i was going from a stationary position to a forward slowly accelerated speed gaining momentum attempting to proceed forward. On Dec 19th 2023 around 10:00 am I test started the car by remote and it started up and then i turned it off, now it is showing that the battery is completely depleted at 1:26 pm

Nov 30, 2023

For the third time, the brake booster has failed on our GMC Terrain. We had the first replaced with an OEM part. That booster failed after 2 weeks. A second OEM brake booster was installed. That one lasted about a year until it failed as well. This time we were traveling down the interstate and interstate speeds. There were no indications of an issue until trying to slow down when attempting to exit the interstate. Luckily it was a long ramp and there was not much traffic as I had to push extremely hard to slow down the vehicle. Knowing immediately what had happened, we noticed a GMC dealership was just down the road and safely made it. We left the vehicle at the dealership and rented a car to continue our vacation. We are now being told that not only did the brake booster fail, but the components entered the engine and caused major damage. The suggested repair is a full engine replacement. This is unacceptable for an issue that GMC has know about and has had recalls for on other years of their vehicles. Not only could my family have been severely injured, or worse, we are not financially able to repair the vehicle.

Nov 21, 2023

My 2019 gmc terrain, vaccum pump failed at about 45000 miles, was driving on the highway and brakes were hard to stop, almost crashed. About 52000 miles, vacuum pump failed again, also while driving on the highway. Brakes were hard to stop, again almost causing me to crash. 69000 miles again vacuum pump failed while driving on the highway, again almost causing me to crash. All times pump was replaced under warranty and now this has caused my engine to fail. i was denied factory warranty, pre certified and extended warranty. Now im stuck with a car with with three years left to pay on it

Aug 28, 2023

There are 3 recalls and one open on this car I was sold by a dealership, none of them ever fixed. I drive to work in the highway the car never had any warning light on but the RPMS would occasionally go up for no reason. I told the dealership the second day that it had issues , they took it and say they fixed the back brakes but did nothing about the engine or transmission whatsoever ever. This was the beginning of may and it was in the shop two weeks. I called my lender to even get out of the loan and a saleswoman even tried assisting me into talking her manager out of the loan because of all the issues. Fast foreword to august I had just gotten a new job and was driving in the night after hearing that ticking or slight knocking noise and I went to my job and as i tried to park the brakes went completely stiff on me! I could not get the car to slow down I had to weave through other cars and people in till it finally coasted to a stop. So I put it in park and immediately after the check engine light came on. I tried to start it and it would start , putter and turn off over and over. I had to end up calling OnStar to have a diagnosis which she said something like solenoid and something being clogged. So it was towed to my residence and before i could get it towed to s shop they lender came and repossessed it because I had missed payments due to losing my job unexpectedly, completely unexpectedly. I told the lender of the problem and the unfortunate troubles I was having to pay for the car but I had just landed a job and could start payment but she didn’t care. She said she is going to tow it . I had my friends dad who is a licensed mechanic look at it before it was towed and he said the car was trash , basically a lemon that there was oil clogged and instead of passing through like it’s supposed to do it being pushed the opposite way and ending up in other reservoirs it shouldn’t be in. I obviously didn’t do that type of damage oil and trans problems I was scammed

Jul 25, 2023

2019 gmc terrain with 45000 miles, regular maintenance performed. Driving on highway 70mps brakes failed with no warning. No issues with brakes or lights coming on up to this point. Brake pedal became stiff very minimal brake working lights began flashing on dash stating "service brake assist". Barely made it off the highway without a catastrophic Collison. Took car in states brake vacuum pump completely failed. Apparently there are many models of gmc/chevy that were recalled and have known issues with the brake vacuum pump. Not sure why the terrain is not included. It needs to be, this was a very dangerous situation. I had children in the car and was very scary! 600$ to repair, and from reading other reviews the pumps are breaking often, sometimes ruining engines. Gmc stand behind your product and fix this!

Jul 18, 2023

In July 2022 vacuum pump failed and created a hard brake situation going 55 mph downhill. Vehicle removed from roadway safely, transported and vacuum pump replaced. In May of 2023 vacuum pump again failed driving at around 25mph, vacuum pump failed catastrophically and blew up inside cam cover. Taken to garage via flatbed and reported car needed a new engine or alternatively we could try a new cam and vacuum pump with hopes pieces did not make it into engine. Now vehicle sits while I still owe money as I do not have 3-5000 to repair it. The fact that this is such a common issue and has happened frequently with other GM models is criminal. I feel as if GM should offer a buyback on affected models or reimburse customers for damages done. Vehicle is outside of warranty currently at 83k first vacuum pump failure occurred at around 70k.

Jul 8, 2023

When parked in home driveway brake lights came on with no one in car or driven during the day. Only way to turn off brake is to remote start & then cut off engine with Fob. Dealer diagnostic unable to find issue & condition didn't occur when at their location.

May 5, 2023

Brake booster failure detected by rumbling sound during braking and certified gmc tech advised of brake booster failure on a 2019 gmc terrain with only 24k miles.

Apr 13, 2023

While driving at the speed limit on U.S. Interstate 83 in Pennsylvania, my 2019 GMC Terrain's braking system suddenly, without any warning, became severely limited. The brake pedal suddenly became very hard to press and the my ability to slow or stop the vehicle became very difficult, requiring a great deal of pressure to even slow the vehicle. The braking system worked perfectly until that moment. If I needed to stop quickly or if I did not have as much leg strength, it is highly likely the equipment failure would have directly resulted in a catastrophic crash. I struggled to get the vehicle safely off the road and stopped. I then had it taken to a certified auto mechanic shop. There, it was found the GM vacuum brake booster pump had inexplicably failed, making the "brake assist" function inoperable. The mechanic was surprised GM had a replacement pump in stock, as he said that is not the norm for other brands. A moment after pressing the brake for the first time as the incident began, a message appeared on the dash stating "Service Brake Assist." There was no pre-failure warning or symptoms. I was in the middle of a 300-mile road trip, having already completed about 220 miles that day, without any notable incident. The cost to replace and install the vacuum pump was about $640.

Nov 14, 2022

Vacuum pump went out while getting off the freeway, going around a roundabout. Brake petal extremely hard to depress and was unable to slow down or stop in a timely manner. Tooke vehicle to GMC for diagnostics and they said the vacuum pump shattered causing damage to my cam shaft and possible engine damage.

Nov 9, 2022

Brakes failed on my car while driving and ran through 4 way stop. Took car to dealership and was told the vacuum pump seized up and sheared off. Asked the dealership what caused the problem and all they could say was normal wear and tear of the vehicle. Dealership called and said it was going to cost $900 dollars to fix the problem. I asked what that included and they said a new vacuum pump and to clean the motor out. Picked the car up on Monday and by Tuesday evening car would not run. Took it back to the dealership and am now told I need a new cam shaft which cost another $2400 to fix. This is a serious safety concern as I had no warning or received no notification that the brakes had failed just went to stop and could not. How long is GMC going to let this issue go before being addressed. How many people have to die first before they recall them as the have already recalled the bigger models of gmc, Chevrolet, Cadillac and Buick for the same reason? I don’t know how people are suppose to afford to fix an almost brand new vehicle that they are still making payments on.. Something should be done ASAP...

Oct 7, 2022

I was driving through a four way intersection with my children and the breaks locked up and I couldn’t get to a stop. This was the middle of September: There are MULTIPLE complaints on this happening with my model and someone is going to die if it’s not recalled. This is a serious safety concern. There was NO warning, or light to prepare me for the problem. Please do something to help us.

Sep 27, 2022

my vacuum booster pump for my brakes keeps needing to be replaced. i had to get it replaced twice now & every single time that it stopped working i was driving on the highway at 65 mph and my brakes just suddenly wouldn’t work and we’re very hard to push down. this has happened twice now

Sep 27, 2022

I was exiting off the interstate and all of a sudden my brakes got hard and wouldn’t let me stop. I tanned thru a red light barley missing another vehicle. The dealership says my vaccines pump went out and caused it to strip my valve cover gasket to shreds and now has stripped the gears in the camshaft.

Aug 26, 2022

We were in the driveway thru lane at a fast food restaurant and all of a sudden the car shut off and the brakes got hard to push in. The car was able to be started at this time but the engine wasn’t working well. We were able to make it home, slowly and carefully. We had the vehicle towed to a Mechanic and this is what was told to us: Possible increased brake pedal effort due to mechanical engine vacuum pump failure. We had it sent to David's Auto Service 219-861-0666. This could’ve been a very dangerous accident if we were driving on the expressway or on a regular street going the normal speed limit. Thankfully we were in a drive thru lane.

Aug 22, 2022

After driving down around 40 miles, the brakes failed when pulling into a parking spot. There was no indication that the brakes were having issues. No sounds or vibrations were felt. I stopped at a stoplight before turning into the parking lot. Then when attempting to spot in a parking spot, the brakes were very difficult to press. Luckily there was not a vehicle or person in front of me. Had the vehicle taken to a dealer and was told it was the vacuum booster that failed. Upon researching, this has been an issue in past GMC models, but I was told there was no current recall for the vehicle. The vacuum booster was replaced for $540 and I drove the vehicle home. The vehicle showed no issues for the first day. On the second day, I went to pull into a parking spot at a park and the same issue with the brakes occurred. I nearly struck a child that was walking in front of the parking spot. Luckily I was able to slam the pedal to the floor and come to a stop. Took the vehicle to the mechanic and was told the same part had broke. That part has been fixed again and has been fine for 2 days so far. I'm scared that it will happen again and I will not be able to stop in time before I hurt someone else or my family. This needs to be addressed. And I believe I am owed compensation from the manufacturer.

Aug 18, 2022

Our son and two daughters were driving on the highway at approximately 70mph when a message came up to say the engine was in "Reduced Engine Power". Although nothing seemed to change. The instruction for such and error message is to "get vehicle to a dealership within the next day." So they slowed to 60mph and continued on their way. About 8-10 minutes later another message popped up that said "Service Brake Assist", at which point they immediately tested the brakes and they worked. But 2-5 minutes later they tested the brakes again and the brakes had completely failed! Zero brakes on the highway! No matter how hard the driver pushed the brake pedal there was 0.0% response. So luckily they were able to coast down to about 10 mph with hazard lights on. But at that point they lost everything. No power steering, no engine, and zero brakes. Thank the lord that they were able to have enough room to slow down and get over to a shoulder prior to the loss of power steering and that they had enough room to coast to a stop. Please help, as we were extraordinarily lucky that day that 3 of our children were able to walk away from such a catastrophic vehicle failure. I just do not want that to happen to anyone else.

Jun 1, 2022

Brakes quit working after service light came on. Vehicle will not stop

Mar 17, 2022

I have been notified that my brake vacuum pump EXPLODED in to my engine, leaving me with limited braking ability. I was driving through a school zone when the brakes went out, I noticed as I was not able to stop at an intersection. This could have led to multiple injuries, including children being in harms way. I had no warning this was coming and now look towards a hefty repair bill. GMC has recalled vacuum pumps in other models but for some reason the terrain is not included. I wonder if there just haven't been enough deaths caused by faulty brake systems for them to cover this model too.

Jan 17, 2022

GMC Corporate Office General Motors Company300 Renaissance Center Detroit, MI 48265 To Whom it May Concern, Been a customer with GMC for a good while despite the issues and troubles we were still loyal to the company. October 31,2021 Sunday, I had sudden lost of my brakes/stalled on my 2019 Terrain SLE while driving to the store close to my area on top of that having less than 30,000 miles in it. Despite the horrible and devastating event I was able to have the truck without any scratch , hit , or had any accident on this event but instead still safely stopped the car down a hill from where I lost my brakes/stalled. Fast forward Nov 2nd had the truck towed to the Milea Pontiac Buick GMC Service And Parts at 3281 E. Tremont Bronx New York 10461. Towing company both from picking up the truck and dropping off Milea had a hard time since the truck was not starting or even able to be placed in neutral to be able to have the truck roll of the flatbed. Nov 2nd Tuesday 2019 GMC Terrain was dropped off at Milea Service and Parts. 1st issue identified by your crew (sort of technical experts) was a bad battery and needs to be replaced, 2nd problem was the computer need to be replaced, 3rd problem was that I had put BAD gas into the tank and the fuel pump need to be replaced after 9 days so fast forward now to Nov 9, 2021.Now finally spoke to a mechanic now stating pistons doesn’t seem to be firing but does not have proper tools to do the test is trying to get from another dealer to be able to diagnose the problem. Nov 20, 2021, still no news as to what is the real issue on the truck we again visited the Milea to find out what is the deal and still without a truck from Nov 2nd to Nov 20 still yours truly has no loaner and no written nor verbal confirmation of what really cause my lost of my brakes/stalled truck. Linda Cuomo the Milea representative has nothing to inform us regarding the cause and instead waiting for a specialist from out of town which claims to be the e

Dec 7, 2021

I received a "service brake assist" message which came on then off. Took the car to a local mechanic who looked it over and said to see dealer as they saw nothing obvious. internet search revealed that many people with terrain said this warning came on when battery was low. Made a service appt for NJ dealer for 12/6/21. on 12/3/21, began a 1200 mile drive from Florida to NJ, after 2 hours, check engine light came on. Took the exit ramp from I 75 and at end of ramp, there was a total braking failure. I had to press very hard to eventually stop. Shut off car, attempted to restart but it would not. Towed to a mechanic who found fluid leakage and a repair bulletin on GM site involving vacuum seal camshaft. #pip5598A diagnostic tip. Internet search reveals many anecdotal instances of same problem. On Monday, 12/6/21, I received an email from GMAC saying that the on board diagnostics had shown a "low battery" concern. The catastrophic loss of braking seems to be connected to a low battery situation. This needs to be looked into by NHTSA.

May 21, 2021

Driving down load. Brake pedal got stiff as a rock. Brakes started to lock up. Almost caused a collision, as the car would not stop