GMC Complaints

Ticking at cold start. 4/02/26 on way home from work. Truck loses acceleration while driving. Bug jumps then display says low power mode. Truck will start but will not move forward or in reverse. RPMs increase but no propulsion. Recall was performed 11/17/25 and passed inspection through Romain GMC Evansville, IN. Called Romain on 4/02/26 and was told someone would return my call 4/03/26. Still waiting. Plan to call Kate Faupal dealership in Henderson,KY on 4/06/26

While backing out of a parking place my husband noticed he couldn't stop the 2025 Acadia and almost hit restraunt behind us, while pusing on the break. He then started to go forward and kept saying "I can't stop it, it won't stop, I'm pushing on the break." The vehicle then went forward and couldn't stop even pushing on the break. I tried pusing the button to turn off the 2025 Acadia a couple times (possible turning back on and because he foot was on the break restarted the vehicle) and then pushed park to see if that would stop. We hit the building in front of us and stopped. The air bags did not deploy so not going that fast. I pushed the button for 911 and they came on to assist and call police and asked if everyone was all right and other questions. Lucky no on was hurt and thank God for that. Tow truck was called and taken to local tow yard.

I purchased my 2025 GMC Acadia on March 26, 2025. // My vehicle began to have electrical/communication/system issues in August 2025. // I took my vehicle to the dealer to address these issues at this time. When I got to the dealership, a representative performed diagnostics, and said "I can't even get a read on this. There is no signal coming from your module. You need to contact OnStar about this." // I called OnStar, and they ran a test, and stated that it is a manufacturing defect that needed to be handled with GMC. //No one informed me of the severity of the safety implications involved. // In March 2026, my vehicle was inoperable. The module controls everything, and was draining the battery at a severely high rate. I had my vehicle towed to the dealership. They tried to deny all liability and said that they weren't the dealership that sold me the vehicle. // I had my battery jumped so I could take it from the dealership have a new battery installed. My vehicle stalled and shut off while I arrived at the Auto Parts store. *** Answer to Questions: Q1: Yes. My vehicle is available for inspection. It is at the dealership. // Q2: My safety and others were put at risk because the brand new batteries were constantly draining and making me stall out in mid-traffic without having any control. // Q3: Yes. The problem has been confirmed by the dealer. They tried (and still are trying) to avoid responsibility. Other reports show that this is a significant safety issue with many GMC vehicles. // Q4: Yes. The vehicle was inspected by the GMC dealership. This is day-16 with no solution. // Q5: Yes, there were issues with the car, as stated above. But absolutely no indication that it would be safety issue. My engine was running normal the night before. No signs that the battery was low or dead and prohibit me from driving safely or that it would shut off.

While driving west on Hwy 20, near Augusta, GA my vehicle motor blew without any warning. I had to guide my dead but rolling truck and trailer to the side of the Hwy against a high retaining wall. The truck shut down and set the brakes after stopping and would not restart, shift into neutral, or move without special two equipment. **when I received the first recall notice I call my GMC dealer and they said their was nothing they could do yet. Later I received a second notice and responded to GMC dealer where the changed the oil and cap. A few weeks/months after that the motor blew. GM has refused to be any help and replacement motor has been on back order for 3 weeks and counting.

When shiftiing to park and turning the car off the message "Action Required Shift to Park". It is difficult to get the message to go away.

The contact owns a 2018 GMC Yukon. The contact stated that the vehicle was taken to a local dealer for service, and the contact was informed that the radiator was leaking and needed to be replaced. The contact stated that there were no signs of a leak prior to taking the vehicle for service. The contact was advised by the dealer that it was a common failure for the year and model vehicle. The manufacturer was contacted and offered a buyback. The vehicle was not repaired. The failure mileage was 128,640.

The contact owns a 2019 GMC Sierra 1500. The contact stated that while stopped, there was an abnormally loud sound coming from the vehicle. The vehicle was consuming an excessive amount of engine oil. The engine and transmission warning lights were illuminated. The vehicle was initially taken to the local dealer; however, the dealer was unable to determine the cause of the failure. The vehicle was later diagnosed, and it was determined that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the issue and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 106,000.

Began with a misfire on cylinder 5 code P0305. Replaced spark plugs, wires, and coil pack. Misfire still existed. Fuel injector on cylinder 5 was stuck open and had to be replaced. Misfire still existed. No spark from new coil pack on cylinder 5, replaced coil pack connector. Misfire still existed, but lifter tick became present. Removed cylinder head and found exhaust lifter on cylinder 5 was bad and needed replaced. Currently awaiting parts delivery (only available through GM dealer). Have been without vehicle for 7 weeks now. Was told this was most likely related to Active Fuel Management.

The service department has identified "gasoline contamination" as the cause of a fuel system failure; however, this diagnosis is directly contradicted by both the shop’s internal test results and independent laboratory analysis.the shop performed an API Gravity test and a Styrofoam cup test.•API Gravity Result (35): According to GM Service Information (GMSi), the standard API range for #2 diesel is 30–39. result of 35 is a textbook "pass" for clean diesel. Gasoline contamination would typically spike this number into the 50s.GMSi protocol indicates that gasoline-contaminated diesel will melt a cup within 30 minutes.results only provided a "softened bottom," which is an inconclusive result per GMSi standards.Sinclair Refinery lab confirms the fuel sample taken from my vehicle is within 100% of factory specifications for diesel, with zero gasoline or DEF detected.Violation of GM Service Protocols even assuming the shop’s diagnosis of contamination was correct, the repair performed deviates dangerously from GMSi requirementsFor a 2024 L5P Duramax that has been cranked with contaminated fuel, GMSi (e.g., Bulletin 16-NA-376) mandates the replacement of the entire high-pressure fuel system, including the pump, both fuel rails, and all eight fuel injectors. shop replaced only the pump and cleaned the lines. This "partial repair" is not a GM-approved recovery procedure for contamination. Reusing potentially contaminated injectors and rails is the primary cause of catastrophic repeat failures.This clearly falls under warranty work and I should not had been charged for this repair. The dealership refusing to acknowledge my concerns and evidence is not only dangerous to the safety of myself and passengers, but raises concern for my vehicles future maintenance status, both inside and out of warranty. This shows a deceptive business practice and complete lack of accountability, compassion and moral understanding for the customer.I am owed a full refund and a warranty claim open

Motor was replaced at 70000 miles it blew rear main on the technician. Now 30000 miles later saying it needs valve body its been in shop 5 weeks now and no ETA on parts. Also the onstar module went out or never worked after engine replaced. The truck has locked up 4 times before the engine was replaced once at 11000 miles. Had hard shifting issues from new dealership kept saying it just needed an update or tuned everytime until 100000 miles warranty was up. On my truck all the extras were were installed when they arrived. Heated and cooled seats. Heated steering wheel, park assist and something else however the truck was already out of manufacturers warranty before the 1st item installed at 50000 miles over a year after I had purchased. Everytime something was put on something else failed. And the grille started peeling immediately after I purchased vehicle and is almost completely gone.