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The 2020 GMC Terrain is a luxury-minded SUV that is designed to elevate the experience for customers. In fact, the GMC motto is “Like a pro,” but in this case, owners feel that the automaker missed the mark. For the time being, the Terrain seems to have a malfunctioning powertrain, vehicle speed control and electrical system.
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NHTSA Complaints for the 2020 GMC Terrain
| Complaint Category | Number of Complaints |
|---|---|
| Unknown Or Other | |
| Engine | |
| Electrical System | |
| Service Brakes | |
| Power Train | |
| Vehicle Speed Control | |
| Fuel/propulsion System | |
| Visibility/wiper | |
| Air Bags | |
| Steering |
Problems with the Transmission
The powertrain is supposed to be designed with a robust transmission that supplies energy to the wheels. However, this Terrain SUV is struggling to perform.
One Edmunds user puts it simply by saying, “Trans whines between 20-28 MPH.”
But, the issues go deeper than just the transmission making noises. Service Bulletin #PIP5720A also talks about one of the many major issues with the powertrain. It states that there could be a transmission fluid leak noticed, which looks like residual fluid from assembly. To determine if it is still leaking, a complete cleaning is required. New vehicles should not have any type of transmission fluid, whether it is currently leaking or was previously an issue. This doesn’t convince anyone that GMC knows how to do things “like a pro.”
Problems with the Electrical System
A vehicle’s electrical system has a big job. It must start the engine, run all of the accessories and supply up-to-date technology to picky users. When this system begins to fail, no one is happy.
Here is a complaint worth reading, left on the NHTSA website. “Every week it’s something different. In motion…no cruise control. No audio. Don’t drive over 50 mph brake problem. Parking brake engages randomly and without user engagement. No AWD. No Stability Traction. This happens so frequently the dash indicators have been reduced to Idiot Lights. At what point do I become concerned? Things appear to resolve when the engine is turned off and back on, sometimes…I compare it to other glitchy technology. However, I potentially could be at an 80 mph cruising speed when I decide to ignore the idiot lights…what happens when a real problem presents and I ignore the dash indicators due to frequent glitches? I’m so disappointed. My 2 previous Terrains were 10 times the vehicle the 2020 model year.”
It turns out that there are so many electrical system problems that GMC can’t keep up. One of the communications, Service Bulletin #PIT5745, talks about how the memory seat module can wake up the Lan BUS, leading to a parasitic battery draw. There’s nothing worse than running out to the SUV in the morning only to find out that the battery is dead and getting to work on time becomes impossible. This is a real problem, especially if the owner wants to make the money to pay the higher Terrain payments.
Problems with the Vehicle Speed Control
The vehicle speed control is designed to help cars move at a specified rate, without much operator input. When this system fails, a lot of people are put at risk, as is seen with the Terrain.
Another NHTSA complaint states, “When cruise control is engaged at 71 mph, holding +Res Button to increase speed and releasing it at 77 mph sets cruise speed too high. Car continues to accelerate. Cruise gets set at 100 mph and accelerates more than desired.”
When it comes to this defect, GMC doesn’t want to talk about any problems. Instead, the automaker has allowed customers to drive blindly down the road, not knowing that it could accelerate on its own. Apparently, the Terrain is so focused on being a “Pro” that it also wants to move every other vehicle out of its way on the road.
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Complaint Data
| Category | Electrical System |
| Date | Mar 10, 2023 |
| State | IL |
| Description | Radio goes from normal volume to as loud as possible while just driving. Scares ya to death! Can't turn volume down with out 1st shutting off radio and turning it back on. Dealship stayed there isn't a problem they could find. Blu tooth cuts in and out and locks the radio up untill you shut vehicle off and restart. Shows you still on a call even though you have disconnected phone from radio. Volume issue has happened several times |
| Category | Engine |
| Date | Mar 03, 2023 |
| State | UT |
| Description | The contact's friend's son owns a 2020 gmc terrain. The contact stated that while her friend was driving at an undisclosed speed, the brake pedal went to the floorboard while depressed. The brakes failed to immediately stop the vehicle. Additionally, the vehicle made grinding sounds while driving. The vehicle was taken to the dealer, where the vacuum pump, exhaust camshaft, and valve cover gasket were replaced; however, the vehicle lost motive power while driving. The vehicle was towed back to the dealer, where it was determined that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and informed the contact that there was no recall associated with the vin. The failure mileage was approximately 48,552. |
| Category | Service Brakes |
| Date | Feb 15, 2023 |
| State | TX |
| Description | The brake system is only working at about 5%. There are known defects with other gmc models of this year and this vehicle should be reviewed . |
| Category | Power Train:automatic Transmission |
| Date | Feb 08, 2023 |
| State | VA |
| Description | 2020 gmc terrain. Consumer stated that their vehicle started pulling and dragging while driving. |
| Category | Fuel/propulsion System, Service Brakes, Steering |
| Date | Feb 07, 2023 |
| State | FL |
| Description | Service brake assists light flashes on dashboard . Steering wheel locks up and jerk's loose suddenly when making a right turn, in these moments when the steering wheel jerks loose ;hands are off taken off the steering wheel otherwise injury can occur. Battery life 2 -yrs old is not performing optimally. Can not hold a sufficient charge and esc light flashes. Vdnt valve leaks discovered. |
| Category | Back Over Prevention: Rearview System Braking, Forward Collision Avoidance: Adaptive Cruise Control, Lane Departure: Blind Spot Detection |
| Date | Jan 15, 2023 |
| State | SD |
| Description | None of these features have ever worked |
| Category | Forward Collision Avoidance: Automatic Emergency Braking |
| Date | Jan 15, 2023 |
| State | SD |
| Description | The emergency breaking system failed to engage. Failure to engage caused collision with another car |
| Category | Seat Belts |
| Date | Jan 12, 2023 |
| State | MI |
| Description | Driver seat belt exhibits signs of fraying in area of belt hidden from view when not in use. When extended, hair-like fibers extend out, primarily from the car-forward side of the belt in the area coming out of the b-pillar and from behind the trim. It is available for inspection. Concerned that this may continue to degrade the integrity of the seat belt over time. There could be something sharp in the retractor, or flash on a piece of plastic trim hidden from view causing this. My understanding is that if there is a small nick on the edge of a safety belt it can tear across, and concerned that this condition could lead to a similar outcome over time and if the vehicle were involved in an accident. Upon taking to local dealership, was advised that this is a normal condition and not a concern. Advisor said technician told him that it is not fraying, it is a normal condition that can be exhibited by the belt fibers, especially towards the edges. They said the central portion of the belt is not exhibiting a similar condition and therefore not a concern. The fibers seem to have grown in quantity since vehicle purchase. I first recall seeing them during the pandemic, although became more concerned over time and finally took in prior to warranty expiration for review. |
| Category | Engine |
| Date | Jan 04, 2023 |
| State | ID |
| Description | I just purchased this vehicle about 2 weeks ago, and was driving through the fog/cold weather and my check engine light came on. Went to o'reillys and had them check the code. Came up as p0299 (my car was telling me that the engine power was decreased) I had a loss of power I could feel while driving as well. The code said turbo under boost. After I got back into town and the weather was warmer and no fog was present, the turbo started working again. I brought my vehicle into the dealer where I bought it from and they took it to their mechanic and supposedly performed an "update". I will see if I continue to have the same issue in cold weather as I live in idaho and go to the mountains often. |
| Category | Service Brakes, Unknown Or Other |
| Date | Dec 31, 2022 |
| State | LA |
| Description | My service brake assist light came on and then within seconds my vehicle then said engine power has been lowered and my vehicle pretty much shut down no steering no brakes couldn't do anything. Took it into the repair shop and my vacuum pump has shattered and now damaged my camshaft. I am aware there's been many other vehicles recalled with gm's vacuum pumps and I'm not sure why my year and model has not been included when it's doing the same thing and not to mention I have seen countless other cases of people saying same things happen to them with their gmc terrains. |
| Category | Engine, Fuel/propulsion System, Power Train |
| Date | Sep 28, 2022 |
| State | OH |
| Description | Turbo failed. Car ran fine with no warning lights. Stopped at red light entering interstate and then could not accelerate which left us stuck in traffic. When it did move it would not shift and took over a mile to get above 20mph in a 65mph zone. |
| Category | Engine |
| Date | Sep 07, 2022 |
| State | CA |
| Description | The engine will never go into 9th gear! What's the point of gmc doing a 9 gear transmission to help with fuel, if it never actually goes into the 9th gear? |
| Category | Power Train |
| Date | Aug 11, 2022 |
| State | MI |
| Description | In january 2022, I purchased a 2020 gmc terrain from a local gmc certified dealership along with an extended warranty. In july 2022, I started to experience intermittent acceleration issues. The issue only presented itself upon vehicle startup and was very sporadic. Upon startup, the vehicle was very slow to accelerate even with the gas pedal depressed to the floor. The vehicle would move at an extremely slow rate of speed for approximately 10 to 15 seconds before the vehicle would engage and actually start moving forward at the expected rate of speed. This would happen 4 to 5 consecutive times before things seemed to "warm up" and run smoothly. It proved to be dangerous at intersections if making a left hand turn into oncoming traffic or during heavy traffic times. From the beginning of july to aug 9th, this has happened on 5 separate occasions. The story is the same, I start the car after it has been sitting for a bit (it's been from several hours to several days) and the issue will present itself without warning. There are no fault or error codes. I've taken the vehicle to my mechanic as well as the dealership where I purchased the car and both have run diagnostics on the vehicle with no luck. My mechanic did drive the car and he experienced the issue first hand but he could not figure out what was wrong. In the event other terrain owners are experiencing this same sporadic acceleration issue with no fault or diagnostic codes, I wanted to make sure we documented our issue. I did not record the dates of the first few instances but the last two have been july 24th and august 9th. |
| Category | Unknown Or Other, Visibility/wiper |
| Date | Jun 13, 2022 |
| State | CA |
| Description | Vehicle has 56801 miles and air conditioning completely went out. I have also replaced windshield wipers twice in 6 months. This is more than any other vehicle I have ever owned (I have had the vehicle 1 year now) |
| Category | Unknown Or Other |
| Date | May 14, 2022 |
| State | TX |
| Description | The engine "auto stop" feature can have enough of a delay to allow the accelerator to be pressed as the engine starts causing it to lurch forward rather than accelerate smoothly. It also can cause a delay when pulling out into heavy traffic. There is currently no way to temporarily or permanently defeat the system on this gm model according to gm service department. Though I am sure it is operating as designed for certain owner driving styles and traffic conditions this can be a serious hazard. Car makers should be required to either disable the feature permanently by owner request or have a method for the owner to bypass the system. With less than 250 miles I have experienced 2 incidents of almost hitting the car in front of me from a stop and 1 of almost being hit pulling into heavy traffic from a stop. I see many other similar complaints and hope this can be addressed before someone is hurt or worse due to it. |
| Category | Fuel/propulsion System |
| Date | May 04, 2022 |
| State | AR |
| Description | I had been fishing at the lake and went to leave and when I got in my car I put it in reverse and backed up then put in drive to pull forward, only I pushed the throttle all the way to the floor and the vehicle was completely unresponsive. I put it back in reverse and backed up a little more then put back in drive and same thing happened. I then put it in neutral and have it gas and with the pedal to the floor it barely revved the engine at all. I put it back in drive and floored it again and started turning the when from side to side still nothing. I put it in park then back in drive and with the gas pedal to the floor it barely started to creep forward. It continued to creep for about 40ft then all of a sudden the throttle worked and vehicle jerked forward. 2 days later I was driving in town with my daughter in the car and slowed down before turning up a steep hill and the vehicle did the same thing. Gas pedal to the floor and wouldn't accelerate. Only this time I almost got rear ended. I have contacted the dealer and told them I need a loaner while my vehicle is fixed and their response was "I don't know what to tell you we don't have any". I called gm and they said they would contact the dealer and see if they just don't have any loaners available or of they don't offer them and said they would call me back. The end of the next day I still haven't heard from them so I reach out to them again this time being told "an owning advisor has already handled your claim, sorry you haven't been updated yet". I don't need updates, I need a safe vehicle for me and my kids! My car has only 57xxx miles plus I bought a 100,000 extended warranty. Please hold gm accountable for their poor quality of vehicles and even worse customer service! |
| Category | Electrical System, Unknown Or Other, Vehicle Speed Control |
| Date | Apr 08, 2022 |
| State | OH |
| Description | Dash had gone black intermittently, did not know what speed I was going. Onstar called oor phone multiple to notify us that our airbags we're offline for ten days no warning light on dash until one to two days later . Took to service was informed that gear shift control, engine control module, passenger presence module and airbag sensor needed replaced. All within a month of purchase of said used vehicle. Vixed under warranty. Then another monther later, got warning on dash saying "conditions not current for shifting", park break light came on, and a p in a yellow circle with a wrench under it came on. Serive did fix vehicle, but could not verify message on dash about conditions not favorable... Also recalibrated breaker. Complained numerous times to dealer about these issues and was told "live with it". |
| Category | Engine, Lane Departure: Assist, Service Brakes |
| Date | Mar 28, 2022 |
| State | OR |
| Description | Unknown... Acts as if its a smart car that's not really a smart car |
| Category | Air Bags, Power Train, Service Brakes |
| Date | Feb 18, 2022 |
| State | LA |
| Description | Brakes hard to press. Almost cause an accident on interstate. Was able to contain vehicle. Took to autozone to assessed and it said powertrain system. Brake booster senor circuit. |
| Category | Electrical System |
| Date | Feb 08, 2022 |
| State | AL |
| Description | Infotainment system shuts off completely. Disables blinker. Bluetooth and usb ports continuously went in and out and wouldn't stay connected. Took to dealership on 02/07/2022 and was advised the system needed an update and the usb port needed to be replaced. Usb port was replaced and software bulletin #20-na-171 was applied. I picked up my vehicle on 02/08/2022 and the infotainment issue has not been corrected. It turned off again. Usb ports seem to be working as they should for now. Also an issue with rear camera. Camera view sometimes shows a fisheye lens instead of normal camera view. Rear camera will sometimes stay on once car is in drive for a few seconds. I also notice a noise and vibration within my gas pedal randomly while driving. Clearly there are multiple issues that gm needs to acknowledge. It's not a coincidence that this is happening to multiple people. |
| Category | Engine, Fuel/propulsion System, Vehicle Speed Control |
| Date | Feb 03, 2022 |
| State | NY |
| Description | As I was driving on the highway in new york on route 17 south near exit 111, I tried to accelerate but when I did the car went slower and the check engine light and traction control lights came on. I was right in front of a huge truck and thank god I was in the right lane that I was able to quickly get on the shoulder and turn the car off. I was able to make it to where I was going, but it was very nerve wracking. I took the car to the dealer service center and was told that it was probably a fuse issue. It turns out my entire engine has to be rebuilt. I have approximately 25,000 on my car, how could it require an entire engine rebuild? The dealer has gotten me two rentals cars that only last 5 days at a time each time and now I'm driving a dealer loaner. It's been 3 weeks and still nothing. I'm still making payments on my car. |
| Category | Exterior Lighting |
| Date | Jan 25, 2022 |
| State | VA |
| Description | Interior lights stays on at night while driving and when parked. Tried turning it off but it won't turn off |
| Category | Electrical System, Engine |
| Date | Dec 31, 2021 |
| State | NC |
| Description | This 2020 gmc terrain has a "feature" called autostop. This is not a switch to turn this off. It would not be so bad if the engine would run for 5 minutes at a stoplight before stopping the engine but it immediately shuts down the engine after a stop. This is getting annoying and dangerous due to the delay in getting the car moving. I have only had the car for a month. I understand that later gmc cars have a disable switch. This car should be recalled and either disable the auto stop permanently or be able to disable the "feature" on demand. Problem: potential crash hazard due to car not starting and damage to battery and starter. |
| Category | Engine |
| Date | Nov 09, 2021 |
| State | MI |
| Description | Loss of oil due to engine defect and need new engine. Engine and car at dealership. Engine has not been torn apart to find cause. Occupants could have died because of engine stoppage... Gm wants owner to pay over 15,000 for new engine and instillation. Car under new car warranty has 24211 miles. No early warning lights of low oil.... Owner took car in immediately when warning lights appeared 9-27-21 and gmc dealership improperly serviced . On 10-14-21 same warning lights reappeared and taken immediately to same close dealership. Now told new engine needed. |
| Category | Electrical System, Unknown Or Other |
| Date | Nov 05, 2021 |
| State | VA |
| Description | While driving instrumental panel and infotainment panel completely blacked out for no reason at all. This is the second time in two days this has happened. |
| Category | Electrical System, Unknown Or Other |
| Date | Nov 04, 2021 |
| State | VA |
| Description | Instrument panel and infotainment system panel completely blacked out while driving vehicle |
| Category | Service Brakes |
| Date | Nov 04, 2021 |
| State | NJ |
| Description | The contact owns a 2020 gmc terrain. The contact stated while driving at various speeds, the vehicle lost brake functionality while depressing the brake pedal. The contact stated no warning light was illuminated. The vehicle was towed to a local dealer where it was diagnosed with needing the vacuum pump replaced. The vehicle was repaired however, the failure persisted. The manufacturer was not informed of the failure. The failure mileage was approximately 40,000. The vin was unavailable. |
| Category | Unknown Or Other |
| Date | Oct 08, 2021 |
| State | VA |
| Description | I had an incident this morning when I put my car in park position it remained in reverse. I took it out of park and put in drive then I put forward but the vehicle still remained in reverse. I turned the vehicle off and it still remained in reverse. Ali controls on infotainment panel was inoperable. ( example: I couldn't turned off or turned radio). |
| Category | Forward Collision Avoidance: Adaptive Cruise Control, Vehicle Speed Control |
| Date | Sep 08, 2021 |
| State | TX |
| Description | Not long after I bought my 2020 gmc terrain my adaptive cruise started disengaging. There are never any warning lights, except the noise and vibration of the seat before it shuts off then tells you it's disengaging. I didn't think anything of it until it's became a regular occurrence in the last month or two. I tell my dealership about it and they drive it but it never disengages on them, so they say nothing is wrong with my vehicle. I have a picture of the "adaptive cruise disengaging" and video of where I can't reset it until after about 15 or so minutes or letting my car set for a while or turning off the engine then it works again. I also have noticed that my auto start/stop hasn't been turning on & off anymore. |
| Category | Electrical System:adas:hill Descent Assist:sensor, Forward Collision Avoidance: Automatic Emergency Braking |
| Date | Jun 25, 2021 |
| State | MI |
| Description | On fairly level ground, reduce speed hill descent control msg has activated (12 mile and maxwell area 2x, rochester hills kohls parking lot exit) and once entering river bend dr. Vehicle has also has had activated brakes on oak hill street in rochester. The vehicle has less than 4100 miles. Very concerning about activated brakes. |
| Category | Unknown Or Other |
| Date | May 31, 2021 |
| State | SC |
| Description | After starting my vehicle on may 28, 2021, the infotainment screen was pink and green with lines. The radio was playing loudly, and I had not previously set it to that volume. Additionally, the volume control button did not work. I headed to the nearest gm dealer, and I did not attempt to turn off the screen. A service representative said I needed an appointment, and I could not be seen until one day during the next week. I needed the turn-by-turn navigation, and I did not know if the issue would worsen or cause other issues, so I asked for a rental vehicle. My vehicle had accumulated less than 10,000 miles, and I have an extended warranty. I was told the vehicle has to be diagnosed before a rental is approved, and their loaner vehicles were out for two and a half weeks. Every dealership I called stated I could not get an appointment that day. I asked gm to call dealers, and nothing worked. Gm said if I rented a vehicle, they would not reimburse me because my vehicle would need to be diagnosed beforehand, with a minimum of a one-day, overnight stay. Normally, the back-up camera takes too long to transition to the radio screen, and it has temporarily appeared black. At less than 300 miles, the vehicle stopped going into drive. That occurred three times, placing me into a dangerous situation the third time, before the selling dealer decided to replace the transmission. At less than 8,000 miles, the driver door switch had to be replaced. I purchased the vehicle with seven accumulated miles. I am still getting familiar with this state, so I need navigation, but it would have caused major safety issues had I attempted to visit family members out-of-state, like I had planned, without turn-by-turn navigation. I had to forgo visiting my family. If more pressing issues had arisen, I would have been completely stranded, over a long weekend, and possibly on a roadside, like before. If I had a family emergency to attend to, the situation would have been horrible. |
| Category | Electrical System |
| Date | Apr 28, 2021 |
| State | NY |
| Description | While starting vehicle the infotainment screen went black and nothing would work. Stayed this way while driving. Stopped turned off car and still didnt work. Was told it was the data communications module. |
| Category | Service Brakes |
| Date | Mar 27, 2021 |
| State | WI |
| Description | Service brake assist message came across screen after I was unable to push down brake pedal. |
| Category | Visibility/wiper |
| Date | Mar 17, 2021 |
| State | OH |
| Description | I am a male of 6'1" height and find it very hard to see out the rearview mirror when I drive my wife's gmc terrain. Because of the limited mobility of the mirror, I am unable to see other cars behind my vehicle without lowering my head and reclining my seat backwards, both of which can be very dangerous to do while driving. I would like to see the mirror adjusted to be longer, or able to be adjusted further upward to improve visibility for taller people, like myself. |
| Category | Unknown Or Other |
| Date | Mar 05, 2021 |
| State | NC |
| Description | When ever I go to turn my steering wheel and I go tp puch in the gas peddle there is a vibration during motion. |
| Category | Power Train, Steering, Suspension |
| Date | Feb 16, 2021 |
| State | CA |
| Description | This vehicle is unsafe due to a violent side to side wobble in the front end much like the jeep death wobble. This happens constantly anywhere from 30mph - 70mph usually after hitting a small bump or when turning hard. The turning aspect is where it has become very dangerous on slippery surfaces as the car then slides out. I live in the mountains where this is a normal occurance. I am actually afraid to drive this vehicle any longer. The dealers have confirmed the issue, but states that gm does not have a fix for this as of now. I have heard this is affecting only the awd terrains and equinox platforms. Gm has been unresponsive trying to get an answer or getting this fixed. The car has been into multiple dealerships several times for this same issue and has been happening since the car turned about 2400 miles and has been happening more frequently since then for the past 6000 miles. |
| Category | Air Bags |
| Date | Dec 21, 2020 |
| State | OH |
| Description | My air bag warning light/dashboard message has come on 7 times in the last 3 weeks, along with 4 other times in the 2 months prior, but the gmc dealership will not investigate since it does not stay on. At the most recent event this weekend, I pressed onstar, and they ran diagnostics and emailed me the "b0085" detected error code, but my dealership will still not investigate, since the light went out. The light has come on at startup and while driving. Warnings have come on 8/27/20, 10/5, 10/8, 10/12, 111/28, 12/2, 12/8(x2), 12/11, 12/14, and 12/19/20. |
| Category | Fuel/propulsion System |
| Date | Nov 18, 2020 |
| State | NH |
| Description | Vehicle was on 1/8 of a tank,I tried to fill, it would only take on 5 gallons of fuel, gas gauge read full. Reported to dealer, there is a 'bulletin' on the vehicle, fuel tank was replaced. After successfully filling tank 3 times, it happened again, returned vehicle to dealer, they could not replicate, brought vehicle home, dealer was able to fill tank with approx 13 gallons, I ran it to 1/8 of a tank tried to fill and it continues to only fill with 2-6 gallons, and record on the gauge a full tank. Very difficult to tell how much fuel is on board. Meeting with gmc district rep 11/19/2020. They suggested I drive it till it runs out of fuel as to see what the gauge reads! Really? Help please! I have photos of the pumps and dashboard to record and time stamp. I need help please! The first occurrence was september 28, 2020 , second occurrence october 16,2020 and third was november 15,2020. The vehicle was returned to the dealer on october 16, they tried to replicate with no luck, vehicle was returned to me november 11,2020! 26 days later. Help! |
| Category | Power Train, Wheels |
| Date | Nov 17, 2020 |
| State | PA |
| Description | Only a month after purchasing my vehicle I started to feel a wobble in the front end when accelerating up hills and turning while on the gas. I took it to the dealer and they changed out the front tires stating that the problem had been fixed. Once again while driving the problem persisted. I took the car back to the dealer again and they said that they could not find anything wrong and suggested that I make an appointment to go for a drive with the mechanic to show them what is happening. I made an appointment. A day before the appointment I received a call from the dealership stating that an employee recently purchased the same car and they are having similar difficulties. They found online that gmc was requesting information from dealers about the problem and was told that I now need to wait for gmc to come up with a solution. My car shakes every time that I drive it, it's awful, and it only has around 6,000 miles on it. I'm not sure what to do because the dealership told me that I have to wait for a solution. They are not even trying to fix anything at this time. Please help. |
| Category | Electrical System |
| Date | Nov 12, 2020 |
| State | LA |
| Description | Twice within the last two months my entire radio shut off, my screen went black and so did my gauges for at least 20 seconds. Then they just came back on and picked up where it left off. |
| Category | Unknown Or Other, Vehicle Speed Control |
| Date | Nov 09, 2020 |
| State | PA |
| Description | Purchased new 2020 gmc terrain w/7miles. Left dealership on my way home, and within 20 miles, received a message on dash-> service - esc - dismiss. Check engine light flashed several times, and the suv slowed down at least 10 miles from 65miles per hour. After engine light stopped blinking, I continues home around 30 miles more with no more problems. Called my sales person the next day, and he did not know what esc was. (electronic stability control) he called me back and indicted the vehicle may need a software update. I told my wife, why would a dealership not check on vehicle software updates before releasing vehicles to the new owners, prior to leaving the dealership. This is called, "being proactive." we were on the highway leaving the dealership after purchasing this new suv. |
| Category | Service Brakes, Wheels |
| Date | Sep 19, 2020 |
| State | CO |
| Description | When reversing out of a parking spot, brakes failed causing accident. Multiple attempts to depress brake pedal with no braking. Hit a parked car. After shutting car off and attempting to move vehicle brakes did engage and respond correctly. Rear damage to terrain occurred requiring towing. |
| Category | Electrical System, Engine, Power Train |
| Date | Aug 30, 2020 |
| State | CA |
| Description | We drove to a farm with a family of 5m kids and an elderly, and parked my car for 2-3 hours in the farm's open area parking lot. Vehicle showed no warning lights, no problems, no issues during our drive to the farm and prior to this trip. Everything was fine when we go there and parked. We were ready to leave the farm to drive back home, but the car simply wouldn't start. The neutral gear didn't work, I attempted many times in 30 minutes to start the car, but it didn't start, continued making the sound of engine attempting to start but not suceeding. 30 minutes later, I decided to give it another try, I was afraid to burn down the starter after attempting so many times. It sounded terrible, screeching metal sound. All of a sudden, the car started. I let it run, afraid to turn it off again. After 15 minutes of running, while we were waiting for roadside assistance to arrive, the vehicle turned off again, all by itself. No one was inside the car, we were waiting outside with the driver door wide open. I called roadside assistance, waited 40 minutes to get a live agent to talk to. The yellow engine light is on. I tried to look in the manual to be able to find anything remotely close to what was happening. Came up with nothing. This was so far the trickiest thing to happen to me. I scheduled an appointment to take the car to the dealership for diagnosis. |
| Category | Unknown Or Other |
| Date | Aug 05, 2020 |
| State | NJ |
| Description | The ac system produces a toxic chemical smell causing the driver and/or passenger to open the windows in order to remove the toxic odor. The smell is intermittent and can be moderate to extremely potent. The vehicle is usually in motion when this occurs and can happen while driving locally and on the highway. The last time this happened was aug. 1, 2020. I have had the vehicle seen at a local gmc dealer 3 time since june, 2020. The vehicle was not driven between march and early june due to the pandemic. |
| Category | Electronic Stability Control, Service Brakes, Vehicle Speed Control |
| Date | Jul 28, 2020 |
| State | MN |
| Description | Every week it's something different. In motion... No cruze control. No audio. Don't drive over 50mph brake problem. Parking brake engages randomly and without user engagement. No awd. No stability traction. This happens so frequently the dash indicators have been reduced to 'idiot lights'. At what point do I become concerned? Things appear to resolve when the engine is turned off and back on, sometimes.... I compare it to other glitchy technology. However I potentially could be at an 80mph crazing speed when I decide to ignore the idiot lights... What happens when a real problem presents and I ignore the dash indicators do to frequent glitches? I'm so disappointed. My 2 previous terrains were 10 times the vehicle the 2020 model year. |
| Category | Structure:body, Suspension, Unknown Or Other |
| Date | Mar 05, 2020 |
| State | TX |
| Description | The complaint I have is the inside front of the car is too small and I cant reach the gas pedal except with my toe. My foot keeps slipping off as I am driving. I have to have the seat way up or I cant reach. I am 5 foot tall woman. This is a ridiculous thing that I have to put up. I drove it for 10 minutes and didn't realize it. I asked for a pedal that is longer and closer to the floor after I had bought it and service people told me they don't have anything to do to fix it. They asked if I had a button to adjust it and I don't. Its on the expensive one. This should be on all vehicles for safety. I wanted to give it back but they never helped me. I have 1100 miles on it . It new still. The other thing this creates is I am up so close to the steering wheel that its almost on my chest in order to reach pedal without having to strain and later having pain in my leg from doing that. I am so disappointed with chuck nash gmc in san marcos , texas. Is there anything to be done by the gmc company. I also told the salesman I wanted a canyon pickup like I had before. I traded that one in due to the fact that the 2017 canyon was always in the shop. Only had it for 2 yrs and 1 month. They were no help! Thank you, [xxx] please help me information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6). *tr |
| Category | Vehicle Speed Control |
| Date | Nov 02, 2019 |
| State | IL |
| Description | When cruise control is engaged at 71mph, holding +res button to increase speed and releasing it at 77mph sets cruise speed too high. Car continues to accelerate. Cruise gets set at 100mph and accelerates more then desired. See link with video of event https://photos. App. Goo. Gl/o7zgeqwcsu7kycv58 see attached picture of owners manual |
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About the Author:
Brian Jones spent more than 20 years working as an ASE Certified Master Tech and Parts Specialist at multiple dealerships. Brian has become an authority in the industry, traveling across the country to consult for car dealerships and contributing his expertise as a writer for several major automotive publications. In his spare time, Brian enjoys working on pickup trucks, muscle cars, Jeeps and anything related to motorsports.
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I purchased a 2020 GMC Terrain SLT with 65000 ish miles on it. After driving the vehicle through fog and cold weather my check engine light came on saying that my engine power was reduced. Pulled code PO299, stating that my vehicle was under boosted. Brought it to where I got it from and they took it to their mechanic and they supposedly “updated” something to do with this issue.
I have a 2020 terrain it’s rebuilt title with 3000 miles almost brand new a week later engine make a noise I took to the dealer it was a bad news the The crankshaft bearing it going bay it’s horrible
After purchasing my 2020 Terrain in November 2019 everything was fine until I noticed grooves in the left front brake rotor at about 4500 miles. I usually change my oil at 5000 miles even though the manual states 7000 so I mentioned the grooves when I had the Oil& filter changed. The answer I got was that it must’ve been a pebble lodged between the rotor and brake pad. I let it go not believing that was the problem. After a couple weeks the grooves got deeper and I returned to the dealership and the car was given to another tech who discovered that the piston within the caliper had broken and part of it grooved the rotor. I had to leave the car for a couple days because they had to order a new caliper and rotor. Everything was fine until I noticed the grooves reappearing again in the new rotor. I once again returned to the dealership and was told it was normal wear. Right!!! Why were the other three rotors groove free. I waited a while and returned to the dealer and seen the service manager and told him all about this problem and said you guys replaced everything but the brake pads on the last repair. Sure enough the pads had something embedded in them so now I had to leave the car again so they could turn the rotor and replace the pads on both front wheels.
Worst and worsen car ever made in the world. car blast on the way and caught fire.
I have 2020 Terrain bought brand new other then some rattling underneath and other noises outside & inside I’ve had no real problems. Today I was going up a small hill and when I pushed the gas to go it made a clicking noise underneath and engine light flashing, Service esc, all wheel drive off flashed, wouldn’t go any faster. So upset I am now at GMC in York ruined my day! I hope they find a loaner if they need to keep 😭
We purchased a 2020 GMC Terrain in October of 2020 brand new. At around 15,000 miles my wife started noticing kind of a popping sound under the right side of the car. At about 23,000 miles I was driving the car and there was a loud bang from that side and the car shot me left across 2 lanes of traffic where i hit the curb before getting it stopped just missing cars at a used car dealership. When it hit the curb it rolled the right front tire into the fender by the door and broke the wheel. The car has been sitting at the GMC dealership for over 2 months and we have been fighting them about it being a defect. they are trying to say it was a collision but the only damage to the car is where the wheel rolled into the fender. there are no pot holes in the road and I do not have a clue what caused the bang.
I have a 2020 GMC Terrain purchased in Feb 2021. There is a transmission issue upon the first drive or so after the car has been sitting still. First in the morning or First in the evening after work it stalls. I have to take my foot off the gas and let it catch up. This is very disappointing as this is not the first purchase from the Chevy/GMC dealership that has had issues (both cars have).
We bought our 2020 GMC Terrain certified used in may of 2020, the vehicle looks sleek and beautiful, the interior is nice, beautiful leather seats, however weeks after purchase we noticed the transmission seems to be slipping or not engaging at very very erratic strange times! Often is putting it in drive after reversing the vehicle won’t go and then we it does it shoots forward. I’ve nearly been in a handful of wrecks as well as my husband. I have taken it in to Chevy where we purchased 3x now and left it with them and the “can not replicate the issue” I said if you google search my vehicle it’s the first issue that’s reported across the board, it is always been reported in their bigger SUVs and trucks, there have even been recalls and class action lawsuits. We got this SUV to have for the next 5 years and it’s simply unsafe to keep. I even contacts GMC directly and they are no help.
I have a 2020 Terrain 2.0 Elevation Edition. I have 0 issues except an annoying rattle on the passenger side A-pillar area. I just hit 17,448 miles and bought it new. Love the car otherwise.
I own a 2020 GMC Terrain, and occasionally the cruise will turn off by itself, and won’t come back until I turn the car off and leave it for 10-15 minutes. The radio sometimes will not let me change the channel and the traction control light comes on by itself. Again, it will all reset after I turn the car off and walk away for a few minutes.
I own a 2020 Terrain and love it. 5,800 miles so far and it’s only been taken back to dealer for scheduled maintenance. I sure hope it stays this way. I am always concerned about the engine constantly cutting off and on again. Now I don’t even notice it. There are lemons, I know, years ago I bought a new Jeep Grand Cherokee and had to return under the Texas Lemon Law. I sure hope the best for the GMC Terrains and their owners.
Lights and turn signals fail regularly, Repeated trips to dealer for repairs, problems are intermittent and they day bring it in while is happening. Of course, when the car is switched off and bac on there appears to be no problem. Power train is sometimes jerkey at 55 to 60 mph. It usualy, takes me some time to hate a car,but not this thing,3 weeks in I hated it.
We purchased our 2020 denali Terain a year ago and have had it into the dealership 4 times now due to check engine light coming on. The first time they said it was a sensor, but of course it went off the day we took it into the dealership and told that if it comes on again bring it back in. The second time the check engine light came on I took it and they “supposedly” replaced it. Then it came on a 3rd time, this time I was told that the “motherboard was bad” supposedly they replaced the entire system. Just last week the check engine light came on again. Just took it into the dealership again to find out what it is this time.
My problem in terrain 2020 is that car’s smoke enter my car cabinet when ac/heater is turned on even during internal circulation mode.
I bought it brand new from gmc agent in jordan and they told me that problem can not be solve
I purchased a new 2020 Terrain with 32 miles from a local GMC dealer. At 350 miles the power steering failed, nearly causing me to crash. The entire steering column was replaced by GM at mile 1,140. Now at mile 3,900 there was a loud pop under the hood, while driving with the cruise control set at 60mph, and the vehicle is in limp mode with the check engine light on. The engine stalls at low rpms and it looks like I’ll miss work to take it back to the dealer tomorrow. I’m ready to be rid of this thing!
Every manufacturer and vehicle model has lemons no doubt. Your comments here make it sound as though all GMC Terrains have terrible problems. Being in IT, I know you can look on forums for software/hardware problems and you will find them to the point you will wonder how the product even works! I own a 2020 GMC Terrain Denali for over a year now and have experienced none of these issues — I hope I don’t — and expect the vast majority of owners will not.