FaultScore report

2018 GMC Terrain problems

Owners have filed 330 complaints about the 2018 GMC Terrain with NHTSA between 2017 and 2026. The largest single group is the brakes. Across this model's run it ranks 3 of 17 worst.

D

68/100

CleanWorst

Measured against the other years of the GMC Terrain, never against another car.

How this is worked out

The numbers

330

Complaints

22

Crashes reported

2

Fires reported

10

Injuries reported

15,615 mi

Median mileage at failure

Half of reported failures happened before this

66%

Failed under 36,000 miles

Inside a typical bumper-to-bumper warranty

NHTSA overall crash rating

From the agency's own crash tests

8

Safety recalls

5 US, 3 Canadian

What kind of bad

The letter says how bad. This says what kind — whether this year drew an unusual number of complaints, unusually dangerous ones, or failures that arrived unusually early.

Complaint volume 64 vs 50 Severity 53 vs 50 Early failure 100 vs 50
The dashed ring is 50 — the national norm. Further out is worse.
Complaint volume — 64
Against the median year of the GMC Terrain. 50 means typical for this model; 100 means roughly double.
Severity — 53
10.3% of these complaints involved a crash, fire, injury or death, against a national rate of 9.7%.
Early failure — 100
66% of failures with a mileage on record happened under 36,000 miles, against a national rate of 29%.

How 2018 compares with every other GMC Terrain

Click any bar to open that year's report.

Complaints filed with NHTSA, by model year. Bar colour is the FaultScore grade: A B C D F ungraded

What breaks on a 2018 GMC Terrain

Every complaint is filed against a part. Follow any row for the complaints about that part alone.

Brakes 81 24.5%

2 crashes, 0 fires · median 58,000 mi

Engine & Cooling 54 16.4%

0 crashes, 1 fires · median 21,500 mi

2 crashes, 0 fires · median 10,300 mi

1 crashes, 1 fires · median 22,000 mi

1 crashes, 0 fires · median 6,050 mi

2 crashes, 0 fires · median 26,000 mi

Airbags 14 4.2%

7 crashes, 0 fires · median 20,575 mi

1 crashes, 0 fires · median 300 mi

Acceleration & Cruise Control 8 2.4%

1 crashes, 0 fires · median 15,615 mi

Stability & Traction Control 7 2.1%

Median failure at 2,034 miles

Steering 6 1.8%

2 crashes, 0 fires · median 11,950 mi

Windows, Mirrors & Wipers 5 1.5%

Median failure at 300 miles

Seats 3 0.9%

Median failure at 8,669 miles

Seat Belts 3 0.9%

1 crashes, 0 fires · median 21,700 mi

Body & Structure 3 0.9%

1 crashes, 0 fires · median 2,290 mi

Child Seats 2 0.6%
Wheels 2 0.6%

Median failure at 12,000 miles

Suspension 2 0.6%

1 crashes, 0 fires · median 11,950 mi

Doors, Latches & Locks 1 0.3%

Median failure at 130,000 miles

Tires 1 0.3%
Lights 1 0.3%

When it fails

Odometer readings owners gave when they filed. About half of all complaints include one.

Under 1,000 miles 17 12.2%
1,000 – 9,999 miles 38 27.3%
10,000 – 24,999 miles 24 17.3%
25,000 – 49,999 miles 20 14.4%
50,000 – 74,999 miles 16 11.5%
75,000 – 99,999 miles 9 6.5%
100,000 – 149,999 miles 9 6.5%
150,000+ miles 6 4.3%

NHTSA crash tests

The agency crash-tested this model year itself. These are its own photographs and star ratings.

Configuration Overall Front Side Rollover
2018 GMC Terrain SUV FWD Later Release
18.5% risk
2018 GMC Terrain SUV AWD Later Release
16.4% risk
2018 GMC Terrain SUV AWD Early Release
16.5% risk
2018 GMC Terrain SUV FWD Early Release
18.8% risk

When owners complained

A spike years after the car went on sale usually means a part wearing out on schedule across the whole fleet — the kind of pattern no single owner can see from inside their own car.

Dec 2017 peak 11 Aug 2026

Recalls on the 2018 GMC Terrain

A complaint is one owner's allegation. A recall is the point at which the manufacturer or a regulator agreed the defect is real and dangerous enough to fix for free — however old the car is.

United States — NHTSA

20V668000

POWER TRAIN:AUTOMATIC TRANSMISSION

General Motors LLC (GM) is recalling certain 2018-2019 Chevrolet Cruze and Buick LaCrosse, 2018-2020 Chevrolet Equinox, Chevrolet Traverse and GMC Terrain, 2018 Chevrolet Malibu, 2019-2020 Buick Encore, Buick Enclave, Cadillac XT4, Chevrolet Blazer and GMC Acadia, and 2020 Cadillac XT6 vehicles. The start/stop accumulator endcap may have missing bolts.

Risk: Missing bolts on the start-stop accumulator endcap could result in a transmission oil leak and may progress to a loss of propulsion, increasing the risk of a crash. A transmission fluid leak in the presence of an ignition source may increase the risk of fire.

18V576000

SERVICE BRAKES, HYDRAULIC:FOUNDATION COMPONENTS:DISC:CALIPER

General Motors LLC (GM) is recalling certain 2018-2019 Chevrolet Equinox, Impala, Cruze, Volt and Bolt EV vehicles, GMC Terrain vehicles, Buick Lacrosse and Regal vehicles, Cadillac XTS and XTS Professional vehicles and 2018 Chevrolet Malibu vehicles. The rear brake caliper pistons may have an insufficient coating causing gas pockets to form, potentially reducing rear brake performance.

Risk: A reduction of braking performance can increase the risk of a crash.

18V358000

FUEL SYSTEM, GASOLINE:DELIVERY:FUEL PUMP

General Motors LLC (GM) is recalling certain 2015-2018 GMC Canyon, 2016-2017 Buick Envision, 2016-2018 Chevrolet Colorado and Malibu, 2017-2018 GMC Acadia, 2018 Buick LaCrosse, Cadillac ATS, Chevrolet Equinox, and GMC Terrain vehicles. The high pressure fuel pump may detach from its mounting flange, possibly resulting in the pump damaging the high pressure fuel line.

Risk: A damaged fuel line can create a fuel leak, increasing the risk of a fire.

18V340000

AIR BAGS: AIR BAG/RESTRAINT CONTROL MODULE

General Motors LLC (GM) is recalling certain 2018 GMC Terrain vehicles. The sensing diagnostic module (SDM) that senses a crash and deploys the necessary air bags may not power down correctly when the vehicle is shut off, causing it to be inoperative when the vehicle is restarted.

Risk: If the SDM becomes inoperative, it will not detect a crash or command the necessary air bag deployment, increasing the risk of injury in the event of a crash.

17V516000

POWER TRAIN:DRIVELINE:DRIVESHAFT

General Motors LLC (GM) is recalling certain 2018 Chevrolet Equinox and GMC Terrain vehicles and 2017-2018 GMC Acadia vehicles. The right front intermediate driveshaft may fracture and separate while driving.

Risk: If the front right intermediate drive shaft assembly separates while driving, the vehicle will lose propulsion, increasing the risk of a crash. If the assembly separates while parked on a grade, without the park brake engaged, the vehicle may move unintentionally, increasing the risk of a vehicle roll-away.

Canada — Transport Canada

Canada runs its own recall programme, and its campaigns do not always mirror the American ones.

Recall 2018461 19,385 units in Canada

Brakes

On certain vehicles, a problem with the rear brake system may cause gas bubbles to form in the brake fluid. This could cause a soft brake pedal feel and a reduction in brake performance, increasing the risk of a crash causing injury and/or damage to property. Correction: Dealers will bleed the rear brakes.

Recall 2018289 73 units in Canada

Fuel System

On certain vehicles, a joint on the high-pressure fuel pump may have been improperly welded during the manufacturing process. Over time, this could cause the weld to crack and create a potential fuel leak. A fuel leak in the presence of an ignition source could increase the risk of fire, causing injury and/or damage to property. Correction: Dealers will replace the high-pressure fuel pump and high-pressure fuel pipe.

Recall 2018279 12,711 units in Canada

Airbag

On certain vehicles, the Sensing Diagnostic Module (SDM), which controls the airbag system, may not shut down correctly when the vehicle is turned off. If this happens, the SDM may not work when the vehicle is started, making it unable to detect a crash or deploy the airbags, and increasing the risk of injury in a crash. Correction: Dealers will reprogram the SDM with updated software to correct this problem. Note: If the SDM is inoperative when the vehicle is started, the airbag warning lamp would illuminate, a “service restraint system” message would be displayed and warning chimes would sound.

Recalls cover specific build ranges, so check your own vehicle by VIN at nhtsa.gov/recalls or, in Canada, Transport Canada.

Complaints that involved harm

Reports where the owner recorded a crash, a fire, an injury or a death.

West Mifflin, PA Crash 2 injured

AIR BAGS

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

NHTSA complaint #11724819 — an unverified report by a vehicle owner.

Spring Hill, FL Crash 1 injured

SEAT BELTS

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.

NHTSA complaint #11662829 — an unverified report by a vehicle owner.

Spring Hill, FL Crash 1 injured

AIR BAGS

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.

NHTSA complaint #11662829 — an unverified report by a vehicle owner.

Plano, IL Crash

FORWARD COLLISION AVOIDANCE: WARNINGS

I was in a car accident

NHTSA complaint #11603299 — an unverified report by a vehicle owner.

Villa Grove, IL Crash

AIR BAGS

Head on collision with a deer destroying the front head light and severely damaging the drivers side door. No airbags were deployed.

NHTSA complaint #11562197 — an unverified report by a vehicle owner.

Elkhart, IN Crash 2 injured

POWER TRAIN

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!

NHTSA complaint #11531130 — an unverified report by a vehicle owner.

The most recent complaints

In the owners' own words, exactly as filed with NHTSA.

Katy, TX

Carry Handle, Shell, Base

I purchased an Evenflo Shyft Intuiti Travel System with a Revolve180 LiteMax NXT infant car seat. The car seat was manufactured on 03/27/2025, model TS100212542. I was notified by Amazon that the car seat was recalled due to a calibration issue with the level indicator that caused the product not to meet applicable federal performance requirements. I contacted Evenflo ParentLink regarding the recall and was informed that Evenflo would provide only a repair kit and would not provide a replacement or refund. Evenflo's proposed interim solutions include using the car seat without the rotating base, using a non-rotating base, or using the rotating base with a modified recline or a load leg. These alternatives do not provide an equivalent remedy for the product I purchased. I specifically purchased this infant seat because the base is designed to rotate. Both parents in our household have back problems, and the rotating feature was an important safety and usability consideration when placing our infant into the seat. Removing the rotating functionality or changing the installation configuration does not provide an equivalent product. Because I did not consider the proposed alternatives acceptable for safely and practically transporting my infant, I purchased a replacement rotating car seat. Amazon ultimately agreed to refund the recalled travel system and arrange pickup of the product. I am submitting this complaint because I believe the recall remedy should be evaluated to determine whether it provides an effective and reasonably equivalent solution to affected consumers, particularly when the recalled product's primary functionality is lost under the proposed interim solutions. I am not reporting a crash or injury.

NHTSA complaint #11760395 — an unverified report by a vehicle owner.

Katy, TX

Tether, Lower Anchor (on car seat or vehicle)

I purchased an Evenflo Shyft Intuiti Travel System with a Revolve180 LiteMax NXT infant car seat. The car seat was manufactured on 03/27/2025, model TS100212542. I was notified by Amazon that the car seat was recalled due to a calibration issue with the level indicator that caused the product not to meet applicable federal performance requirements. I contacted Evenflo ParentLink regarding the recall and was informed that Evenflo would provide only a repair kit and would not provide a replacement or refund. Evenflo's proposed interim solutions include using the car seat without the rotating base, using a non-rotating base, or using the rotating base with a modified recline or a load leg. These alternatives do not provide an equivalent remedy for the product I purchased. I specifically purchased this infant seat because the base is designed to rotate. Both parents in our household have back problems, and the rotating feature was an important safety and usability consideration when placing our infant into the seat. Removing the rotating functionality or changing the installation configuration does not provide an equivalent product. Because I did not consider the proposed alternatives acceptable for safely and practically transporting my infant, I purchased a replacement rotating car seat. Amazon ultimately agreed to refund the recalled travel system and arrange pickup of the product. I am submitting this complaint because I believe the recall remedy should be evaluated to determine whether it provides an effective and reasonably equivalent solution to affected consumers, particularly when the recalled product's primary functionality is lost under the proposed interim solutions. I am not reporting a crash or injury.

NHTSA complaint #11760395 — an unverified report by a vehicle owner.

Huntsville, AL

UNKNOWN OR OTHER

Approximately 3 miles from my residence my car display flashed "Reduced Engine Power" and slowed down. When I reached a stop sign and tried to stop, my brakes were stiff and I was unable to stop. I went through the stop sign. I continued to my residence at 10mph and backed into a parking space with a curb to help stop my vehicle. I turned the car off and called a mechanic to come look at my car. I explained the events and let him know it would not start. He checked the codes after hooking it up. The error codes were for Cam shaft and crank shaft, etc. I was instructed to not try and start the car because further damage could occur and it would need the camshaft pulled to determine the extent of damage.

NHTSA complaint #11759068 — an unverified report by a vehicle owner.

Huntsville, AL

ENGINE

Approximately 3 miles from my residence my car display flashed "Reduced Engine Power" and slowed down. When I reached a stop sign and tried to stop, my brakes were stiff and I was unable to stop. I went through the stop sign. I continued to my residence at 10mph and backed into a parking space with a curb to help stop my vehicle. I turned the car off and called a mechanic to come look at my car. I explained the events and let him know it would not start. He checked the codes after hooking it up. The error codes were for Cam shaft and crank shaft, etc. I was instructed to not try and start the car because further damage could occur and it would need the camshaft pulled to determine the extent of damage.

NHTSA complaint #11759068 — an unverified report by a vehicle owner.

Huntsville, AL

SERVICE BRAKES

Approximately 3 miles from my residence my car display flashed "Reduced Engine Power" and slowed down. When I reached a stop sign and tried to stop, my brakes were stiff and I was unable to stop. I went through the stop sign. I continued to my residence at 10mph and backed into a parking space with a curb to help stop my vehicle. I turned the car off and called a mechanic to come look at my car. I explained the events and let him know it would not start. He checked the codes after hooking it up. The error codes were for Cam shaft and crank shaft, etc. I was instructed to not try and start the car because further damage could occur and it would need the camshaft pulled to determine the extent of damage.

NHTSA complaint #11759068 — an unverified report by a vehicle owner.

at 117,000 miles Charleston, WV

SERVICE BRAKES, HYDRAULIC

The contact owns a 2018 GMC Terrain. The contact stated that while her son was driving 45 MPH, the brake pedal was firm while depressed. There was no warning light illuminated. Due to the failure, excessive force was needed on the brake pedal to stop the vehicle. The contact was able to drive the vehicle to the residence. The following day, the vehicle was taken to an independent mechanic. The mechanic diagnosed the vehicle with an inoperable vacuum pump that was shredded and needed to be replaced. The manufacturer was notified of the failure and informed the contact that the VIN was not under recall. The contact was then referred to the NHTSA Hotline for assistance. The vehicle was not yet repaired. The failure mileage was approximately 117,000.

NHTSA complaint #11758514 — an unverified report by a vehicle owner.

Southgate, MI

ENGINE

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.

NHTSA complaint #11755920 — an unverified report by a vehicle owner.

Southgate, MI

SERVICE BRAKES

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.

NHTSA complaint #11755920 — an unverified report by a vehicle owner.

at 95,300 miles Hometown, IL

SERVICE BRAKES, HYDRAULIC

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.

NHTSA complaint #11754433 — an unverified report by a vehicle owner.

Nazareth, PA

SERVICE BRAKES

Vehicle would slowly roll even when break is applied. It was confirmed by the service center that the break booster vacuum pump was only reading 8 when it should be at 27. It was not making enough pressure. The vehicle would not stop when break was applied.

NHTSA complaint #11752244 — an unverified report by a vehicle owner.

Bensalem, PA

ENGINE

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)

NHTSA complaint #11751119 — an unverified report by a vehicle owner.

Bensalem, PA

SERVICE BRAKES

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)

NHTSA complaint #11751119 — an unverified report by a vehicle owner.

Bensalem, PA

FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING

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)

NHTSA complaint #11751119 — an unverified report by a vehicle owner.

Caruthersville, MO

SERVICE BRAKES

Vacuum pump that supplies vacuum to brake booster failed without any warnings beforehand leaving us without the ability to stop. Luckily was able to avoid an accident.

NHTSA complaint #11742410 — an unverified report by a vehicle owner.

Marquette, MI

SERVICE BRAKES

While traveling on the highway in traffic, brakes became very stiff when depressed after attempting to slow down to exit. Was able to put full bodyweight into the brake pedal to slow enough to exit and navigate to the gas station right off the exit. Had to roll stop signs and unsafely navigate traffic because brakes were not working. Service Brake System warning light came on after the incident.

NHTSA complaint #11739875 — an unverified report by a vehicle owner.

Covington, GA

FUEL/PROPULSION SYSTEM

Gas leaking from the hood. High pressure fuel pump

NHTSA complaint #11739681 — an unverified report by a vehicle owner.

at 260,000 miles Marion, IL

SERVICE BRAKES, HYDRAULIC

The contact owns a 2018 GMC Terrain Denali. The contact stated while the contact's daughter was driving, the brake pedal was depressed, however the vehicle failed to stop as intended. In addition, the contact stated that the brake pedal was unusually hard when depressed. The vehicle was taken to the dealer where the vehicle was purchased. The contact stated that the service brake vacuum pump failed while the vehicle was at the dealer. The vehicle was diagnosed with a failed service brake vacuum pump and a failed engine. The contact was informed that the service brake vacuum pump, the CAM Shaft and the engine needed to be replaced. The vehicle was repaired. The contact stated that the failure was a known failure of the vehicle. The manufacturer was not made aware of the failure. The failure mileage was approximately 260,000.

NHTSA complaint #11737294 — an unverified report by a vehicle owner.

at 260,000 miles Marion, IL

ENGINE

The contact owns a 2018 GMC Terrain Denali. The contact stated while the contact's daughter was driving, the brake pedal was depressed, however the vehicle failed to stop as intended. In addition, the contact stated that the brake pedal was unusually hard when depressed. The vehicle was taken to the dealer where the vehicle was purchased. The contact stated that the service brake vacuum pump failed while the vehicle was at the dealer. The vehicle was diagnosed with a failed service brake vacuum pump and a failed engine. The contact was informed that the service brake vacuum pump, the CAM Shaft and the engine needed to be replaced. The vehicle was repaired. The contact stated that the failure was a known failure of the vehicle. The manufacturer was not made aware of the failure. The failure mileage was approximately 260,000.

NHTSA complaint #11737294 — an unverified report by a vehicle owner.

Waterloo, NY

SERVICE BRAKES

We just got off the bus thruway and my brakes pedal got hard to press and it was hard to stop car I had to push on brake dry hard to get the car to stop it was jarring and o had to get my some and o to a safe place. Garage said it’s brake assist and he researched there’s is an active law suit against GM bc lots of Moses and models have this issue although they claim to know nothing about it

NHTSA complaint #11726554 — an unverified report by a vehicle owner.

West Mifflin, PA Crash 2 injured

AIR BAGS

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

NHTSA complaint #11724819 — an unverified report by a vehicle owner.

Somersworth, NH

UNKNOWN OR OTHER

The control knob that controls AWD, 2WD,Off-road, and 4 x4 AWD. Just stopped working. Stuck on 2WD mode. I did have it checked for any codes, even though, there is NO check engine light is on.

NHTSA complaint #11722587 — an unverified report by a vehicle owner.

at 245,000 miles Detroit, MI

POWER TRAIN

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.

NHTSA complaint #11721631 — an unverified report by a vehicle owner.

Gray, GA

SERVICE BRAKES

Faulty Brake Vacuum Pump!!!! 2018 GMC Terrain @ 119254 miles--- NO warning! Brakes were hard to press, did not work and I rolled into ditch to prevent an accident. I see hundreds of people with same issue now that I Am having to research. This was very scary. I was told it was as a brake booster pressure sensor. But that was not the problem. It is the brake vacuum pump. This is so dangerous. Why is GMC not correcting this issue? This is insane. GM issued multiple technical service bulletins on vacuum and booster issues starting in 2017. Why hasn't anything been done?

NHTSA complaint #11721477 — an unverified report by a vehicle owner.

Fifield, WI

UNKNOWN OR OTHER

Vehicle will not shift out of park, despite replacing the valve body, putting in a new battery, and transmission fluid. It has been this way since mid January. The codes don’t make sense and there is no current recall, nor have we had this vehicle for very long. It has 48,000 miles on it and is having this issue. Very disappointed.

NHTSA complaint #11720574 — an unverified report by a vehicle owner.

Damascus, GA

ENGINE

Brakes were hard to engage or press when stopping due to Vacuum pump stop working. Had to replace the vacuum pump

NHTSA complaint #11719833 — an unverified report by a vehicle owner.