GMC Hummer EV Problems — All Years, Common Issues & Reliability

Under full acceleration on flat, dry pavement, the vehicle suddenly pulls hard to the right or left without any steering input. The steering wheel does not move, but the vehicle abruptly changes direction, requiring immediate counter‑steering to avoid losing control. This happens every time under full acceleration and has been confirmed by two GMC dealers. GM Corporate states this is “normal,” but the behavior is unsafe and could cause a crash. Two GMC dealers reproduced the issue and confirmed the sudden directional pull under full acceleration, but both stated it is ‘normal.’ GM Corporate also acknowledged the behavior but claims it is within manufacturing tolerance. The vehicle still pulls violently to one side under full acceleration, creating a serious safety risk.

Charge port door on vehicle will not open regardless of what you do.

While operating my 2024 GMC Hummer EV at a low speed in a school zone, I came to a complete stop at a stop sign and began making a left turn. As I initiated the turn, the steering wheel suddenly locked and became unresponsive. I was unable to turn the wheel back to the right or regain control of the vehicle’s direction. At the same time, the vehicle did not respond as expected when attempting to stop. Because I could not steer or properly control the vehicle, I collided with another vehicle. The impact with the other vehicle is what ultimately brought my vehicle to a stop. During the incident, multiple warning messages appeared on the dashboard, including a message indicating: “Service Steering System.” My vehicle sustained minimal damage due to its height (a bent side step), however the other vehicle sustained damage. Police responded to the scene and a report was filed. I was NOT issued a citation. (see report attached) The vehicle has since been towed to Northwest Hills Chevy/GMC in Torrington CT for inspection by the GMC manufacturer. This incident raises serious safety concerns, as the sudden loss of steering control at low speed could have resulted in significantly more severe consequences under different circumstances. I was in a school zone at dismissal time going to pick up my son. This appears to be a potential mechanical or electronic steering system failure. I believe this represents a serious safety defect that should be investigated to prevent similar incidents.

The frunk latch on the vehicle becomes faulty and does not recognize the hood being latched and secure when it is. While driving, the vehicle without warning will immediately limit speed to 26mph regardless of existing vehicle speed. This has occurred multiple times when driving on the highway with the vehicle immediately decelerating and then saying the hood (frunk) is open. This poses a serious danger to not only the occupants of the vehicle but also those around them on the highway. This occurred when traveling at highway speed in the middle lane. This resulted in the inability to change lanes to pull off the highway due to the drastic reduction in speed in reference to the other vehicles on the highway causing a high stress and high risk situation for the driver and occupants.

Visibility / Defogging / Defrosting issues are main safety concerns. Every winter for the last 3 years, the heater fails and blows only cold air. This is intermittent throughout the year, but recurring. With cold-weather driving conditions, it creates an unsafe driving experience when windshield and windows can't defog or defrost properly. The problem has been reported several times to the dealership and it was never fully resolved while under warranty. Each time I took the vehicle to the dealership for servicing with temporary adjustments. Dealership now states a heater module needs to be replaced at my expense although the same codes and part affected while under warranty. The component/part number needing replaced is part 85757074 (hybrid electric coolant heater module per dealership). There were several service vehicle warning lights and diagnostic codes were shared with dealership when dropped off for repairs.

Severe recurring roof water intrusion on 2022 GMC HUMMER EV; repeated failed repairs; interior rust/corrosion; safety concerns in high‑voltage EV. Vehicle: 2022 GMC HUMMER EV Edition 1
VIN: [XXX] Current mileage: ~12,000 miles
 
My vehicle has a recurring defect involving severe water intrusion into the cabin through/around the removable roof panels/roof sealing areas during rain. Despite repeated dealership repair attempts, the vehicle continues to leak. The ongoing water intrusion has caused visible corrosion (rust) on interior metal structures, including the floor area and seat rails/seat mounting areas. The corrosion indicates prolonged moisture exposure inside the cabin. The dealership has attempted to repair this water intrusion issue approximately six (6) separate times, and the defect remains unresolved. First documented repair attempt: 03/14/2023 (issue presented to dealership for correction) Most recent repair attempt/out-of-service: 12/29/2025 to 01/06/2026
The vehicle has spent weeks at the dealership across these attempts, including time waiting for parts and work completion. Even after these repairs, the vehicle is still leaking and the corrosion is still present. 
Because this is a high‑voltage electric vehicle, I am concerned that water ingress and corrosion are compromising electrical wiring/connectors and safety systems located in/near the cabin floor and seat areas (including areas where sensors and connectors may be present). I am concerned this could increase the risk of electrical short, malfunction of safety systems (including airbag sensors), and in a worst case scenario a fire risk if moisture reaches sensitive electrical components. I can provide photos/videos of active water intrusion and corrosion and all repair orders upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The vehicle was no longer able to charge, and therefore could be stranded. Yes, the vehicle is currently back at the dealership and available for inspection. Without ability to charge, the vehicle could shutdown and not be able to restart. Yes. It was at the dealer from 6/27 to 8/20 and then the issue re-exhibited on 9/3 and it was returned to the dealership. Yes, it was reviewed by the dealership and returned, only to happen again within 100 miles. Yes, the Service Engine Soon light appears.

The super cruise self driving system is entirely defective and faulty, this is a safety issue.

On August 11, 2025, at about 2:52pm, my vehicle was at a complete stop at an intersection awaiting the traffic light to turn green. There was a slight downgrade slope towards the intersection. The vehicle one-pedal driving was enabled. Weather was sunny with no wind or rain. Suddenly, the vehicle started vibrating violently and started rolling into the intersection. I pressed on the brake pedal but the vehicle continued to vibrate and the vehicle rolled into the middle of the adjoining lane of traffic. There was no traffic on the roadway and no other vehicles were affected. My vehicle had come to a compete stop in the roadway and I attempted to accelerate through the intersection but the vehicle would not move. I recycled the power to the vehicle and placed the vehicle into drive and proceeded to drive through the intersection. I do recall that when I was pressing the brake pedal, the vibration felt somewhat similar to vibration of the ABS brake system when the tires are losing traction but the vibration was much more pronounced. I pulled the vehicle onto the side of the road and checked the driver information display. A "Service ESC" notification appeared on the driver information panel followed by "One-Pedal Driving Unavailable Use Brake for Stopping". No other warnings or notifications were observed after this incident and the vehicle seems to be driving normally. I was able to re-enable the one-pedal driving mode the next morning.

The contact owns a 2025 GMC Hummer EV. The contact stated while driving at an undisclosed speed, the message "Forward Collision Avoidance System Unavailable" was displayed. The contact stated while another vehicle pulled in front of the contact's vehicle, the forward collision avoidance system and the side-view sensors safety features failed to engage. The vehicle was taken to the dealer, but was not diagnosed due to a schedule error. The diagnostic testing appointment was rescheduled for a later date. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was unknown.

On [XXX], my [XXX] son was riding in the back seat of our 2025 GMC Hummer EV (VIN: [XXX] ) and reported his seatbelt felt loose. I pulled over and discovered the seatbelt bracket was completely detached from the vehicle frame. The bolt was present, but the nut that secures the bracket was entirely missing, leaving the belt nonfunctional and my child at risk of serious injury or death in the event of a collision. This is a catastrophic failure of a federally regulated safety system. I immediately contacted GMC and the dealership, explained the issue, and stated the vehicle was unsafe to drive. Despite this, I was told to drive the vehicle in for service on 6/9. The dealership confirmed the nut was never installed during manufacturing. However, instead of repairing the defect properly using OEM hardware and torque specs, the dealer used a generic lock nut found in their shop and said it “should hold.” No engineer signed off on the repair. There were no warning lights or messages. The issue became apparent only after my son noticed the looseness. The vehicle also has other documented issues: mirror folding failure, seat cushion defect, hydraulic frunk failure, swing gate malfunction (fixed), and a squeaky rear door. All were diagnosed on 2/28/25 and parts were ordered. I received no follow-up. When I returned on 6/9, nothing else was repaired. The advisor said the original technician had left and the new one couldn’t proceed. I also own a second 2025 Hummer EV (VIN: [XXX] ) and am now concerned about its integrity. This experience has caused ongoing emotional distress. GMC’s failure to inspect, respond, or properly repair a critical seatbelt defect demands NHTSA investigation and possible recall. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2025 GMC Hummer EV. The contact stated that while the vehicle was stationary, the brake pedal was depressed, and several unknown warning lights illuminated. The contact stated that while the vehicle was idling for several minutes, several unknown warning lights illuminated. The vehicle was then taken to a dealer where it was inspected by an engineer who stated that the system was extremely sensitive, and the dealer stated there was no additional assistance that could be provided. The vehicle was not repaired. The contact stated that while driving at an undisclosed speed on another occasion, several unknown warning lights illuminated. The contact was informed the system was extremely sensitive and the issue would reoccur. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 2,300.