2020 GMC Terrain

During heavy rain, the sunroof on my Terrain leaked badly enough to allow a substantial amount of water into the vehicle. The rear floor area became completely saturated, and the sunroof controls stopped working. I brought the vehicle to Hudson Cadillac Buick GMC in Poughkeepsie, New York, to have the problem diagnosed and repaired. The resulting repairs and water-damage cleanup cost me nearly $3,000 out of pocket. I was advised that the damage was not covered by my warranty or by my insurance. What concerns me most, however, is that this does not appear to have been an isolated incident. While my Terrain was at the dealership, I learned that four other GMC Terrains were also at the dealership experiencing water damage related to leaking sunroofs. Mine was the fifth. Finding five Terrains at the same dealership with what appeared to be similar water-intrusion problems was extremely concerning to me and made me question whether this is a recurring issue with these vehicles. I also have a video provided by the dealership documenting the water damage to my vehicle, and I am happy to provide that video, my repair invoice, photographs, or any other documentation you would like to review. They went to great lengths to dry the vehicle, which was especially important to me because I was extremely concerned about hidden moisture and dangerous mold. Thankfully, after their work, there is no odor and no indication of remaining moisture or mold, and I am very satisfied with the quality of the repair and cleanup. The extent of the water damage was frightening. At one point, I was genuinely concerned that I might have to get rid of the vehicle simply because I was afraid of the long-term consequences of having so much water inside it. I am very grateful that the dealership was able to restore the vehicle so thoroughly but there is still a possibility that the repair will fail and I will have to replace the sunroof module.

Backup camera stopped working and displays a blue screen stating “service backup camera.” This was an issue when the vehicle was under 3 year manufacturer bumper to bumper warranty and was fixed by dealer at no cost. Now this same issue has occurred again approximately 3-4 years later. I thought at first this was an issue specific to my vehicle but now after doing research I see this is an issue across several GMC Terrian vehicles and other GM vehicles. This issue should be fixed by the manufacturer for all vehicles affected. Vehicle owners should not be responsible to fix faulty parts from the manufacturer.

On June 7, 2026, I was driving my 2020 GMC Terrain. I was going at about 40MPH along a very busy main road. While slowing for a red light the Check Engine Light turned on and the car displayed a notice about reduced engine power. Seconds later, the brake pedal became stuck and would not press down all the way and I lost braking ability. The car rattled/shook violently, made a grinding noise, and then the engine shut off and the car stopped abruptly, narrowly avoiding hitting the car in front of us. I turned on the hazard lights. I was not able to get the car to start again, nor was I able to get the car to shift into any other gear including neutral. We were nearly hit by other vehicles multiple times while attempting to get the car to move again, and to get myself and my child safely out of the road. Myself and multiple bystanders attempted to engage the transmission interlock override multiple time. We were eventually able to engage it and push the car to the side of the road. This failure created an extremely unsafe situation for all involved as this road is very busy and there were numerous near-collisions both with my disabled vehicle, and with other drivers serving out of the way and into other lanes at the last second. As time went on and the battery drained, most of the car's exterior lights turned off and other drivers had a hard time seeing my car. I used a strobe flashlight to alert other drivers but this required that I had to stand in the road near the vehicle. Police were called immediately when I found that we could not move the car out of the road, but they did not arrive. Ultimately the vehicle was stuck and inoperable in a travel lane for over two hours. The car was then towed to a nearby repair shop. The mechanic evaluation stated that the brake vacuum pump had failed resulting in loss of braking ability and expensive damage to the engine and other components. The manufacturer is aware of this issue. See: Thieme, et al. v. General Motors LLC.

Filled up with gas and went to leave gas station and was still rolling to come to a stop and car shut off and would not crank back up o couldn't put in neutral to even move out of the way. After about 10 mins I was able to crank it back up. No lights came or was on and battery was showing 14.5 now that im sitting battery is showing 12.8. Oil was just changed 4 days ago. Just purchased used less then 3 weeks ago. Im at a lost has 122,272 miles on it

The article below appears online, 4/13/2026. I have the exact same problem with my 2020 GMC Terrain Denali and I would like other GM vehicles added to their Chevy recall. They use the same parts within GM's product lines. As background info, I went to the dealer, Matick Buick GMC, 29300 Telegraph Rd, Southfield, MI 48034 on Jan. 14, 2026 for repair. I was told water infiltrated my backup camera and its harness. Matick said very few parts are available in the USA. Still not fixed and it is dangerous. Yes is the answer to the 1st 4 general guideline questions. The 5th question is NO. READ MORE TRENDING NEWS: Chevrolet has recalled 271,770 vehicles over an issue with the rearview camera. Some 2023 to 2025 Chevy Malibus were recalled because the camera screen may show a distorted or blank image, the National Highway Traffic Safety Administration said. Dealers will replace the camera at no cost to correct the issue. Owners will get letters in the mail alerting them to the problem after May 18, the agency said. For more information, call Chevrolet at 800-222-1020. The company’s internal recall number is N262551720. The vehicle identification numbers can be searched on NHTSA.gov.

I own a 2020 GMC Terrain with approximately 110,000 miles. While driving in winter, the vehicle suddenly lost cabin heat and defrosting capability. The temperature gauge began fluctuating and the cooling fans continued running after the vehicle was shut off. A mechanic diagnosed the cause as a cracked radiator that allowed coolant to leak out, which is a known frequent failure on this model. Because the heater stopped working in sub-freezing temperatures, this created a safety hazard due to lack of defrosting and heat while driving. The failure occurred without warning, and no coolant warning light was displayed before the heater stopped working. The vehicle was not overheating at the time, but the loss of heat and defrost made winter driving unsafe.

The rear backup camera in my 2020 GMC Terrain failed. I first noticed and noted that the image was 'cloudy' on 5/3/2023, and it became very bad by 1/22/2024. On 7/1/2024, the image stopped working completely, replaced with a blue screen on the dashboard screen. I ordered a new camera and replaced it myself on 8/1/2024. Because the dealership did not mention any safety effects or recalls, and instead quoted me a very expensive repair estimate, and the vehicle was out of its 3 year warranty, I assumed it was my responsibility to repair this feature. However, I have seen recent news articles where other vehicles have been recalled by NHTSA for similar problems with backup cameras.

My a/c went out within 2 years of having the car in 22’. In 2025 i have had nothing but problems, the radio will go out when im driving for about 2 hours and it resets, the screen goes black, music stops, navigation stops and then it turns on like nothing happened. It happens everytime I drive 2+ hours. Back in September of 2025, I was on my way to work when I was stopped at a red light, it turned green and then my brakes locked up and I couldn’t drive my car had shut off, and wouldn’t come back on. I was stuck in the middle of the road not knowing what happened as the car had driven fine up until i stopped at the red light. Then tonight November 21,2025 around 0315 I was leaving work, I started my car, my car threw up a message that said “Low fuel, 0 miles” I had half a tank of gas when I got to work. I turned my car off then back again and it did the same thing. I let my car sit for a second and then my Gas gauge started to slowly increase to the correct amount of gas. Then when I got home (3 mile drive from work) I turned my car off and then back on and this time when I turned the car on my brakes were locked and I couldn’t start my car. All of the Engine lights were on so I turned the car off and then let it sit for a minute before trying to start it. When I tried to start it this time, I couldn’t. It’s like the car had died and was getting no power. I couldn’t lock my car, no lights were working, I couldn’t turn it on or start it. Some time went by and my interior lights were on so then I started the car and it’s almost like my car reset. I can’t see my tires PSI, the clock went to midnight (it was about 0330) it was all just very weird!!