2018 GMC Terrain: What to check before buying
Owners have filed 201 complaints with NHTSA about this car, most about the brakes, transmission, and electrical. The 9 checks below target those problems, in the order you would do them at the car.
2018- Owner complaints
- 201
- Recalls
- 5
- Crashes reported
- 13
- 10 injuries
Your inspection sheet
Tick items off on your phone at the car, or print it. Ticks stay on this device.
0/9 checked
2018 GMC Terrain: inspection sheet
Paperwork and questions
Before you go, or before you touch the car0/2
Walk-around and cabin
Engine off, key in hand0/2
Cold start, engine bay, and underside
Ask the seller not to warm the car up first0/2
Test drive
At least 20 minutes, with some highway0/3
These checks are specific to this model year. For tires, body panels, fluids, and the other basics every used car needs, use the general inspection guide.
Which Terrain is it?
EPA figures for each version of the 2018 GMC Terrain. Use them to confirm you are looking at the version that was advertised, and as a yardstick on the test drive.
| Version | Drive | EPA rating |
|---|---|---|
| 1.5L 4-cylGas | AWD, FWD | 26–28 mpg |
| 2.0L 4-cylGas | AWD, FWD | 23–24 mpg |
| 1.6L 4-cylDiesel | AWD, FWD | 32 mpg |
- The 2018 GMC Terrain was sold in three versions. Confirm which one this is from the window sticker, the engine cover, or the VIN report before you compare prices.
- Reset the trip computer at the start of the drive. A Terrain that averages well under the EPA 23 mpg combined on a mixed route may have an engine or tire problem.
Check the odometer against these mileages
Owners report these failures starting around the mileages below. A car inside one of these ranges deserves a closer look at that part, or records showing it was already fixed.
Pitted brake rotors
14,000–30,000 miles
Brake vacuum pump failure
50,000–121,000 miles
Why these checks: what owners reported
NHTSA complaints for the 2018 GMC Terrain, grouped by the part owners named. Open a row to read what goes wrong.
Brakes581 crash
The brake pedal suddenly turns rock hard and stopping distances stretch out, often at highway speed or on an exit ramp. Most reports trace this to the camshaft driven brake booster vacuum pump. The pump can shatter and send metal into the engine, damaging the camshaft or ruining the engine. A Service Brake Assist message or check engine light sometimes appears, but many drivers say there was no warning. Failures cluster between about 50,000 and 112,000 miles. Some drivers stopped only with the parking brake. A smaller group reports pitted rotors at low mileage.
Transmission381 crash
Most of these reports are about the transmission. Drivers describe revving without an upshift, slipping into neutral when pulling away, jerking into gear, and sudden drops in speed along with warnings to pull over. Some vehicles go into reduced power mode and recover after a restart. Repeat dealer visits often fail to find a cause, and in one case a replacement transmission failed again. One crash followed a harsh shift that jerked the steering wheel. Other reports repeat the vacuum pump failure that destroys camshafts or engines, and one describes a driveshaft coming loose during 4WD engagement.
Electrical291 crash
Infotainment screens go black, reboot, switch stations on their own, or scramble icons and saved settings. In one crash, the backup camera and parking alerts failed while reversing. Door locks work only some of the time, sometimes after a car wash, and dealers have found corroded wiring harnesses in a door and in the rear bumper. Some engines fail to restart after auto stop or shut down in traffic, which can leave the doors and windows locked. One fire-related report describes a burning smell from the dash vents. Several filings here actually describe brake vacuum pump failures.
Engine16No crashes
An Engine Power Reduced warning followed by a stall, sometimes in moving traffic, is the main pattern. Dealers often blame a cracked vacuum pump that damages the camshaft or sensors, and several engines need full replacement. Many drivers say no warning light came on first, and some had to swerve into a median to avoid a collision. Diesel owners report catalytic converter failures and heavy blow-by. In one case, a converter failed at 101,650 miles and the dealer had no replacement part. Auto stop also draws complaints about hesitation and lurching on restart.
Airbags116 crashes
Airbags that fail to deploy in serious collisions make up most of the crash reports. These include driver-side impacts at highway speed, a frontal hit, and a deer strike. Six of the 11 reports involve crashes. One side curtain airbag reportedly burned through clothing and caused 2nd to 3rd degree burns. The rest describe a Service Safety Restraint System warning and airbag light that comes and goes. In one case, a dealer found a failed driver's side front impact sensor. Owners who bought used are often unsure whether a 2018 recall covers their vehicle.
Steering62 crashes
Power steering assist cuts out with a Power Steering Reduced message, or the wheel feels heavy and will not return to center. In one case, a dealer recalibration helped for only about a month. Two crash reports involve sudden loss of control, with 2 people injured. In one, the vehicle veered right and rolled. The other was blamed on a ball joint failing during a turn. Other complaints describe the wheel snatching back in reverse while several warnings light up, and snow packing into the wheels and causing shimmy at highway speed.
Fuel system4No crashes
Fuel leaks lead this small group. One report describes a steady drip from the fuel tank and cites a recall for the same model year. Diesel fuel line leaks were reported on more than one fleet vehicle. Another report describes turbo failure with power loss, whining or grinding noises, blue smoke, and a check engine light. One more objects that auto stop shuts the engine off at stop signs, then lags before restarting when pulling into traffic.
Seats3No crashes
Seat height adjustment causes most of these few reports. In one, a manual lift lever keeps coming off its track and needed a second dealer visit. In another, a driver seat will not raise for better visibility. The most serious report describes a bolt snapping on the front passenger seat frame with a loud pop, leaving the seat rocking back and forth before the vehicle had moved.
In owners' own words
Excerpts from complaints Terrain owners filed with NHTSA, as written. Listen for the same symptoms on your test drive.
I was coming to a stop with my vehicle and the brakes would not work. I carefully got my car home and to a shop. It was determined that the break booster pump broke which caused metal parts to go into the engine. Now my engine is blown! Bought my car brand new in 2018 and kept up with regular vehicle maintenance has 90k miles.
Filed with NHTSA, January 2023
The brakes are extremely hard to engage while driving. All 4 rotors are pitted with less than 30k miles. Doing some online research this is a common problem and should be addressed. I just did my first set of brakes at 100,000 miles on my truck.
Filed with NHTSA, February 2022
Car is losing go power when accelerating on to interstate. It’s like the transmission loses power, the d illuminates, and then it kicks in to drive. It puts us at risk for an accident and I had a semi almost hit me because of this. This has been reproduced at the mechanic shop as well. No warnings before this happens
Filed with NHTSA, September 2023
My vehicle put itself in park in the middle of an intersection while waiting to make a left turn in the middle of rush hour traffic. The car could not even be placed in neutral to be pushed out of the way of oncoming traffic. Narrowly avoided a collision.
Filed with NHTSA, September 2023
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.
Filed with NHTSA, December 2025
I was driving my vehicle, there was no indication that the vehicle was in need of servicing or that something was wrong with the vehicle, no check engine lights were on. The vehicle stopped in mid traffic, just completely shut down in active traffic. I had to serve my vehicle in to the curb/median to stop if from hitting traffic ahead of me.
Filed with NHTSA, May 2023
Beaverton GMC did repair work on my vehicle. During the inspection they said they found the radiator leaking from a number of spots and it needed replaced. It has never leaked and did not need replaced. Why did they do it? I as for the parts but they tossed them and would not give them to me.
Filed with NHTSA, December 2021
How the 2018 compares with other Terrain years
Complaints for this year next to the average for the other model years, area by area.
The 2018 has the most owner complaints of the 8 Terrain years we cover, about 3.0 times the average of the others. Newer years have had less time to collect complaints, so compare like with like.
- Brakes5813
- Transmission3814
- Electrical299
- Engine166
- Airbags110
- Steering61
Where the 2018 fits in the Terrain's history
Redesigns and mid-cycle updates change what can go wrong.
The 2018 is the first model year of the Terrain's second generation (2018–2024). First years of a redesign often carry teething problems that GMC fixes in later years, so the checks above matter more than usual.
GMC updated the Terrain for 2022, so a 2018 does not have those changes.
What changed for 2022 (not on a 2018)
- Updated front and rear end
- Exterior LED lamps
- New trim levels including AT4
- Discontinuation of low-end SL trim
Should you avoid the first year of a redesign? See the 45-car study.
Recalls to confirm (5)
Recall repairs are free at any GMC dealer, but the seller may never have had them done. Check each campaign number against the VIN.
20V668000TransmissionOct 2020
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.
Fix: GM will notify owners, and dealers will inspect the start-stop transmission accumulator and replace it if any bolts are missing, free of charge. The recall began December 15, 2020. Owners may contact GMC customer service at 1-888-988-7267, Buick Customer service at 1-866-608-8080, Chevrolet customer service at 1-800-222-1020 or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N202313440.
18V576000BrakesAug 2018
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.
Fix: GM will notify owners, and dealers will bleed the vehicle's brake system, free of charge. The recall began October 11, 2018. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 18279.
18V358000Fuel systemMay 2018
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.
Fix: GM will notify owners, and dealers will replace the high pressure fuel pump, and high pressure fuel pipe, free of charge. The recall began July 2, 2018. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 18188.
18V340000AirbagsMay 2018
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.
Fix: GM will notify owners, and dealers will reprogram the SDM with updated software, free of charge. The recall began June 29, 2018. Owners may contact GMC customer service at 1-800-462-8782. GM's number for this recall is 18179.
17V516000TransmissionAug 2017
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.
Fix: GM will notify owners, and dealers will replace the right front intermediate drive shaft assembly, free of charge. The recall began August 25, 2017. Owners may contact GMC customer service at 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is 17329.
Also looking at these instead of a Terrain?
Cars shoppers compare with the GMC Terrain, with their own 2018 checklists.
2018 owner complaints, side by side
- Kia Sportage147
- 2018 GMC Terrain201
- Toyota RAV4330
- Hyundai Tucson362
- Chevrolet Equinox382
- Nissan Rogue718
- Honda CR-V1,960
