2018 GMC Terrain Problems

While driving my 2018 GMC Terrain, the vehicle suddenly displayed an “Engine Power Reduced” warning and the brakes became extremely hard to press. The vehicle experienced a sudden loss of normal power-brake assist while it was in motion, creating a serious safety risk because significantly greater pedal force was required to stop the vehicle. I was able to pull over safely. After stopping, the vehicle would crank but would not start. The vehicle was towed to a GMC dealership for inspection. The dealership documented that the vehicle had a suspected failed/broken vacuum pump, a damaged exhaust camshaft, and a damaged exhaust camshaft actuator. The dealership subsequently documented that the engine was severely sludged and stated that the sludge caused the vacuum pump to fail, which then caused the exhaust camshaft to twist and damage the exhaust camshaft actuator. The dealership’s written diagnosis recommends replacement of the exhaust camshaft, exhaust camshaft actuator, vacuum pump, and associated one-time-use parts. The dealership has also documented diagnostic trouble codes P0014 and P0017. The failed vacuum pump and related components should be available for inspection upon request. The vehicle has been inspected by a GMC dealership, which has documented the suspected vacuum pump failure and resulting engine damage. The sudden loss of power-brake assist occurred while the vehicle was being driven and created a potentially dangerous loss of braking capability. I am reporting this because I believe the failure of the vacuum pump and resulting loss of brake assist may represent a safety-related defect requiring investigation, particularly because the vehicle experienced a hard brake pedal without prior warning.

The contact owns a 2018 GMC Terrain. The contact stated that while driving at an undisclosed speed, the brake pedal was depressed; however, the vehicle failed to stop as intended. The contact stated that the brake pedal was abnormally firm. The brake pedal was depressed to the floor, and the vehicle came to a stop. The check engine warning light was illuminated. The vehicle was towed to the dealer. The vehicle was not diagnosed. The contact referenced an unknown recall; however, the VIN was not associated with a recall related to the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 95,300.

While driving my 2018 GMC Terrain, the vehicle suddenly displayed an “Engine Power Reduced” warning and the brakes became extremely hard to press. The vehicle experienced a sudden loss of normal power-brake assist while it was in motion, creating a serious safety risk because significantly greater pedal force was required to stop the vehicle. I was able to pull over safely. After stopping, the vehicle would crank but would not start. The vehicle was towed to a GMC dealership for inspection. The dealership documented that the vehicle had a suspected failed/broken vacuum pump, a damaged exhaust camshaft, and a damaged exhaust camshaft actuator. The dealership subsequently documented that the engine was severely sludged and stated that the sludge caused the vacuum pump to fail, which then caused the exhaust camshaft to twist and damage the exhaust camshaft actuator. The dealership’s written diagnosis recommends replacement of the exhaust camshaft, exhaust camshaft actuator, vacuum pump, and associated one-time-use parts. The dealership has also documented diagnostic trouble codes P0014 and P0017. The failed vacuum pump and related components should be available for inspection upon request. The vehicle has been inspected by a GMC dealership, which has documented the suspected vacuum pump failure and resulting engine damage. The sudden loss of power-brake assist occurred while the vehicle was being driven and created a potentially dangerous loss of braking capability. I am reporting this because I believe the failure of the vacuum pump and resulting loss of brake assist may represent a safety-related defect requiring investigation, particularly because the vehicle experienced a hard brake pedal without prior warning.

The vehicle has had regular maintenance, oil change, and inspection including the brakes. My boyfriend is visiting me in [XXX] from the [XXX]. OnXXX while driving the vehicle the engine started. Making a ticking noise especially during idle and when accelerating in idle. About 15 minutes after the ticking stopped and all of a sudden there's a complete loss of breaks they locked up and the driver was unable to efficiently stop while going down a hill Road. Driver had to use the emergency brake to make the other brakes release and then the brakes from there would not work even though you could stomp on them stand on top of them there was no breaking power anymore. Vehicle was brought into a GMC dealership on the following Monday where they confirmed the issue was a failed vacuum pump connected to the engine and camshaft which is a known safety issue to GMC as part of an ongoing open case they had specialty coverage and bulletins regarding the Tahoe and Sierra but neglected to include the terrain on this issue. Cold the GMC manufacturer in both [XXX] and [XXX] to try and get cost assistance and specialty coverage as the vehicle as well under the mileage requirements but have been giving the push around and zero assistance. The risk to the drivers and passengers lives was significant as we were on the highway for1.5 hrand thankfully the brake lost didn't happen in full during that time. The repairs were completed and paid for in full by the client which should have been covered by the dealership and we are looking for cost recuperation and are now being ignored. Receipts are here to substantiate the claim. The ABS light is no longer on there was no warnings on the vehicle showing any issues or any codes as OnStar was called and diagnostics were received and the diagnostics came back clear prior to this happening, and following the break failure. Lack of codes and warnings is life-threatening and serious. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2018 GMC Terrain. While attempting to shift to reverse(R) out of a parking spot, the message “Transmission Unable to Shift” was displayed on the instrument panel, and the transmission was unable to shift into reverse(R). The contact called for tow truck assistance. The vehicle was unable to shift into neutral (N). The contact stated that prior to the transmission failure, the “Service Transmission Soon” message was displayed. The vehicle was towed to a local dealer to be diagnosed, and it was determined that the transmission had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 245,000.

The contact owns a 2018 GMC Terrain. The contact stated that while driving at various speeds, there was an abnormal grinding sound coming from the vehicle while transitioning to 4WD. The contact continued driving and the driving sound became more frequent while shifting into 4WD. Upon inspecting the vehicle, the contact discovered that the driveshaft had detached and was hanging down from the suspension. An independent mechanic was contacted, and the contact was informed about NHTSA Campaign Number: 17V516000 (Power Train); which the mechanic associated to the failure. The contact called two local dealers and was informed that the VIN was not included in the recall. The manufacturer was notified of the failure, and the contact was referred to the NHTSA Hotline to report the failure. The vehicle was not repaired. The failure mileage was approximately 160,000.

The infotainment system will just randomly start going haywire and when it happens, you cannot use the touchscreen. It will try to randomly delete app icons such as the camera, it will try to delete connected phones, it will try to delete radio favorites and it will move app icons all around. These are just a few examples of things that happen.

The contact owns a 2018 GMC Terrain. The contact stated that the transmission was shifting gear erratically. The contact stated that the doors were locking and unlocking independently, and the instrument cluster was blank. There was an abnormal beeping sound coming from the vehicle. Additionally, the contact stated that while at a traffic light, the Auto START/STOP feature delayed to respond. OnStar was alerted, but the contact declined to perform the service. The contact was in contact with the independent mechanic who sold the vehicle, but no assistance was provided. The local dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 130,000. The VIN was not available.

The vehicle has had regular maintenance, oil change, and inspection including the brakes. My boyfriend is visiting me in [XXX] from the [XXX]. OnXXX while driving the vehicle the engine started. Making a ticking noise especially during idle and when accelerating in idle. About 15 minutes after the ticking stopped and all of a sudden there's a complete loss of breaks they locked up and the driver was unable to efficiently stop while going down a hill Road. Driver had to use the emergency brake to make the other brakes release and then the brakes from there would not work even though you could stomp on them stand on top of them there was no breaking power anymore. Vehicle was brought into a GMC dealership on the following Monday where they confirmed the issue was a failed vacuum pump connected to the engine and camshaft which is a known safety issue to GMC as part of an ongoing open case they had specialty coverage and bulletins regarding the Tahoe and Sierra but neglected to include the terrain on this issue. Cold the GMC manufacturer in both [XXX] and [XXX] to try and get cost assistance and specialty coverage as the vehicle as well under the mileage requirements but have been giving the push around and zero assistance. The risk to the drivers and passengers lives was significant as we were on the highway for1.5 hrand thankfully the brake lost didn't happen in full during that time. The repairs were completed and paid for in full by the client which should have been covered by the dealership and we are looking for cost recuperation and are now being ignored. Receipts are here to substantiate the claim. The ABS light is no longer on there was no warnings on the vehicle showing any issues or any codes as OnStar was called and diagnostics were received and the diagnostics came back clear prior to this happening, and following the break failure. Lack of codes and warnings is life-threatening and serious. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

It starts to “warn” you by the seat doing whatever it does and the dash lights up collision flashing and slams on the brakes when nothing is even around

Gas leaking from the hood. High pressure fuel pump

Turbo boost went out in my vehicle and 3 others with the same engine, different makes/models. Vehicles were serviced at Grayling Car Care 4430 M-72, Grayling, MI 49738 (989) 348-3200. Significant power loss, sluggish acceleration, poor fuel economy, and often strange noises (whining, grinding), accompanied by blue smoke from burning oil and a lit check engine light, with the severe risk of catastrophic engine damage from broken parts entering the engine if driven, requiring prompt replacement. It's generally unsafe to drive with a bad turbo, as metal fragments can destroy the engine.

My car was t-boned on the driver side and no airbags deployed. The outer door and window exploded with the force. We were also hit from behind

My car said to me this not that there is something wrong with the Service Safety Restraint system! It was fine last night when I got home! I just bought this car a month ago and everything was fine and now my air bag light is on and will not go off!

My husband and son were involved in an almost fatal accident on 07/08/23 in our 2018 Terrain. My husband described that the vehicle spontaneously veered to the right uncontrollably, he was unable to steer to correct the vehicle, unable to brake, they went airborne, hit several poles and a transformer, rolled and flipped several times. All the airbags deployed.After the accident, I found a recall notice from back in 2017, I believe, regarding the drive train. My husband was extricated from the vehicle. My son wasble to cut the seatbelt and crawl out the window. From what my husband explained (he was the driver), this sounds like what they experienced during the collision. I never received a recall letter from GM as this is something I would of taken care of and have got repaired. Please see the photos and the recall I found. Please let me know if there is anyone else I need to contact regarsing this collision.My car was almost paid off. My husband and son could of lost their life. Please advise. Thank you!

Multiple warning lights are appearing at once (Automatic brake assist, forward collision assist, parking brake released) When the car is put in reverse, the radio turns off for a brief moment and the steering assist warning shows on the dash. The steering wheel snatches back in the opposite direction causing a safety concern. The car also completely cuts off after the auto-stop takes effect at red lights causing me to have to pump the brakes at least twice to re-ignite and be able to accelerate.

The headliner fabric detached somehow from the panoramic track causing the fabric to hang down obstructing the rear and back window view causing a safety hazard. The automatic forward collision alert will come on for no reason since this has happened. The problem has not been reported to insurance or the manufacturer yet but GM is my next call. This is a safety hazard due to the obstruction of visibility to safely make turns or change lanes. This happened August 5th while driving with the windows up. It just dropped down still attached to the front of the track and the rear.

My driver seat does not raise or incline so it gives me like a visibility when I’m driving. The seat needs to be raised so I have more visibility on the road while I’m driving.

The contact owns a 2018 GMC Terrain. The contact stated that the transmission was shifting gear erratically. The contact stated that the doors were locking and unlocking independently, and the instrument cluster was blank. There was an abnormal beeping sound coming from the vehicle. Additionally, the contact stated that while at a traffic light, the Auto START/STOP feature delayed to respond. OnStar was alerted, but the contact declined to perform the service. The contact was in contact with the independent mechanic who sold the vehicle, but no assistance was provided. The local dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 130,000. The VIN was not available.

My driver seat does not raise or incline so it gives me like a visibility when I’m driving. The seat needs to be raised so I have more visibility on the road while I’m driving.

The strike plate on my rear driver door fell off. The plate and bolts are in perfect condition but the backing is gone. Multiple body shops have attempted to locate the backing, which is somewhere between the interior and exterior metal body pieces, and gave been unable to. Every body shop I've taken it to also says that they have never seen anything like this happen before. They are reluctant to fix it because that would mean cutting through the body to replace the backing for the strike plate then welding, sanding, and painting in the area they cut and they worry about the integrity of the striker and functionality of it as well, as they've never had to do a repair like this before. One of the body shops was also a certified GM repair shop at the dealership from which the car was purchased and even they have said the same as the others. They also encouraged me to report this to the NHTSA and GM as well because they've never seen it happen or heard of it happening and they are concerned because it is a safety issue. I know that there is a similar recall on some newer GMC Terrains and wonder if my issue would be related to the recall or if it's is a separate issue all together. The striker was barely touched and someone exited my back seat and fell off into a parking lot, I was able to recover the striker and both bolts which are completely undamaged and unworn. This is my only vehicle so I now have to hold my door shut with bungee cords and tape in order to use my vehicle. I have a child who is still in a car seat and must remain in the back seat for safety but now my backseat is also not very safe because of the door. A few days prior to the striker falling off my door would not close fully flush with the rest of the vehicle but still closed, locked, and remained closed with no other issues.

Rear side windows in hatch area leaked filled up spare tire compartment with about 3-4 gallons of water. Now navigation doesn't want to work, sunroof not working, electric systems are not working right

The contact owned a 2018 GMC Terrain. The contact stated that while driving and nearly coming to a complete stop in the right lane, another vehicle driving approximately 40-50 MPH crashed into the rear of the vehicle, causing the contact to hit her face against the steering wheel, and the contact became unconscious temporarily. The contact stated that upon regaining consciousness, the contact noticed that the vehicle had moved to the grass by the left lane of the road, where traffic was going in the opposite direction. It was unknown whether the vehicle was involved in a second collision. A message advising that an accident was detected and inquiring whether 911 should be contacted was displayed. The contact stated that the air bags failed to deploy, and the front driver's side seat belt failed to retract as needed. A bystander opened the driver's side door to verify that the contact was safe. The contact noticed that she was bleeding significantly and was unable to move the right shoulder and the neck. The emergency units assisted the contact out of the vehicle. The emergency units placed braces on the contact's neck and placed the contact on a stretcher. The contact was transported to the hospital, where the contact underwent X-rays and CT scans. The contact was informed that she had sustained a concussion, lumbar injuries, a fractured nose, loss of taste and smell, laceration on the inner and outer side of the bottom lip, carpal tunnel on the right hand, severe whiplash, laceration on the right shoulder, and a cut behind the right ear. The contact was in the process of undergoing MRIs. A police report was filed. The vehicle was towed and totaled, but was still under investigation. The dealer was not notified of the failure. The manufacturer was notified of the failure, and a case was filed; however, no further assistance was provided. The failure mileage was unknown.

The "Service Safety Restraint System" warning light appears on the dashboard and warning chimes continually sound. To my knowledge GMC had a recall for this in 2018. I purchased the vehicle in 2021. I contacted GMC and told them this issue and they informed me that there are no recalls on the vehicle. My concerns being that airbags are fully functional.

TL* THE CONTACT OWNS A 2018 GMC TERRAIN. WHILE DRIVING 80 MPH, THE REAR PASSENGER TIRE SHOOK AND VIBRATED LOUDLY. THE CONTACT TOOK THE VEHICLE TO ED BOZARTH CHEVROLET (2001 S HAVANA ST, AURORA, CO 80014, (720) 746-2716) WHERE IT WAS DIAGNOSED THAT THE TIRES WERE FAULTY. BOTH REAR TIRES WERE REPLACED, BUT THE FAILURE CONTINUED. THE MANUFACTURER WAS NOT NOTIFIED. THE FAILURE MILEAGE WAS UNKNOWN.

THE VEHICLE WAS IN MOTION MAKING A RIGHT HAND TURN AND IN THE TURN THE OPERATOR LOST CONTROL OF THE VEHICLE CAUSING HER TO STRIKE A CURB THEN HEAD FOR ONCOMING TRAFFIC. WHEN IT WAS ALL SAID AND DONE IT LOOKED LIKE THE BALL JOINT HAD FAILED CAUSING THE LOSS OF CONTROL. A BYSTANDER SAID HE HEARD A LOUD POP AND LOOKED UP AND WITNESSED THE VEHICLE SLIDE INTO THE CURB AND THEN SEE THE FRONT LEFT TIRE LOCK UP AND THE VEHICLE COME TO A STOP.

TL* THE CONTACT OWNS A 2018 GMC TERRAIN. WHILE DRIVING 80 MPH, THE REAR PASSENGER TIRE SHOOK AND VIBRATED LOUDLY. THE CONTACT TOOK THE VEHICLE TO ED BOZARTH CHEVROLET (2001 S HAVANA ST, AURORA, CO 80014, (720) 746-2716) WHERE IT WAS DIAGNOSED THAT THE TIRES WERE FAULTY. BOTH REAR TIRES WERE REPLACED, BUT THE FAILURE CONTINUED. THE MANUFACTURER WAS NOT NOTIFIED. THE FAILURE MILEAGE WAS UNKNOWN.

WHILE DRIVING ON A SNOW- COVERED ROAD WITH ANY AMOUNT OF SNOW, THE SNOW GETS PACKED INSIDE OF THE WHEELS AND THROWS THE WHEEL BALANCE OFF CAUSING THE STEERING WHEEL TO SHIMMY BADLY AT HIGHWAY SPEEDS. I HAVE TO REMOVE THE SNOW PACK EVVERY DAY, AND I BELIEVE THAT THIS IS AN AERODYNAMIC DESIGN FLAW WITH THE WHEELS WHERE THE SNOW DOESN'T GET BLOWN OUT OF THE WHEEL WHILE THE CAR IS IN MOTION.

At ignition, vehicle tire pressure monitoring system indicated low tire pressure in rear right wheel of 9psi; right front tire indicated 38psi and left front and rear indicated 38psi. Driver verified pressure as good at 38psi in rear right tire with hand held gauge. While operating the vehicle on the interstate, vehicle driver experience a flat tire in the right front passenger tire. Tire Pressure monitoring system indicated 41psi in right front tire (even while flat), and indicated right rear tire at 0psi even though it was visually inflated.

TL* THE CONTACT OWNS A 2018 GMC TERRAIN. WHEN DRIVING DOWNHILL, THE VEHICLE STALLED AND WOULD NOT ACCELERATE. THERE WERE NO WARNING INDICATORS ILLUMINATED. THE CONTACT PULLED THE VEHICLE OVER AND HAD IT TOWED TO ANCHOR BUICK GMC (1 AUTOMOTIVE BLVD, ELKTON, MD 21921, (443) 406-4623) WHERE IT WAS DIAGNOSED THAT THE TRANSMISSION CLUTCH NEEDED TO BE REPAIRED. THE VEHICLE HAD NOT BEEN REPAIRED. THE MANUFACTURER WAS NOTIFIED. THE FAILURE MILEAGE WAS 4,200.

Radio, hands free calling, and light on mirror shorting out. None of them work. It’s like it has a short in the wiring.