GMC Complaints

My GM Dealership completed the GM 6.2 Engine Inspection and recommended Oil Replacement as part of the 6.2 Engine Recall. Roughly 5,000 miles after this service, the engine failed. I attempted to accelerate from 45-65 miles per hour while getting on the highway, and the engine seized up. I was able to coast/steer the vehicle to the side of the road. The vehicle's starter could not crank the engine. I had the vehicle towed to the shop where the dealership confirmed the engine had seized. The dealership and GM replaced the engine under a warranty repair. I am making you aware of this situation, as the manufacturers suggested solution to the engine issue (The Change in Oil Type, Filter and Cap) did not prevent the engine from failing.

In 2023, the vehicle began exhibiting erratic transmission shifting behavior, including harsh and unpredictable shifts while driving. The vehicle was taken to a GMC dealer for diagnosis and repair. Recently, the vehicle developed additional drivetrain and engine control issues related to the crankshaft position sensor circuit. The vehicle stalled while driving on a highway mountain overpass with multiple vehicles traveling behind me. When the stall occurred, the vehicle shifted into park and would not restart for several minutes. This created a hazardous situation due to loss of propulsion in active traffic at highway speed and limited shoulder space. Following diagnosis, the servicing dealer determined that the engine wiring harness requires full replacement due to internal wiring integrity issues affecting critical engine control signals. The crankshaft position sensor and related wiring are essential for engine timing and propulsion. Loss or corruption of this signal can result in reduced engine power, erratic transmission behavior, stalling, or no-start conditions. The earlier erratic shifting behavior appears consistent with conditions described in GM Technical Service Bulletin 21-NA-149, which identifies engine harness-related causes for drivetrain and shifting concerns. This issue appears to involve degradation or defect within the engine wiring harness affecting engine management and transmission operation. Given that this condition resulted in a highway stall and temporary inability to restart, I am reporting this for investigation as a potential safety-related defect involving loss of propulsion.

My truck started knocking and while driving home and it died on me in the middle of a busy street and would not start. I waved down a police officer and he kept me safe from cars hitting from behind.Come to find out it was the bearing rod and now I’m getting my engine replaced. My truck is a 2024 gmc sierra with 9,000 miles on it.

Dear Sir/Madam, For the 3rd time now, my transmission is being rebuilt. After purchasing it from the dealership and it was still under warranty GMC Bakersfield rebuilt the transmission, then again in 2020 at 119,000 miles it broke down again and All Automatic in Bakersfield rebuilt it for $3500 and now here it is 2026 and only 60.000 miles later again All Automatic is having to rebuilt the transmission again and asking now for another $4950. I was excited to finally hear there was a recall, only to find it was only for 2014 GMC Acadia's. The transmission have failed again and yes it is available for inspection at All Automation in Bakersfield, CA on Quantico. During the course of breaking down the my safety and the safety of my children was at risk. My vehicle was jumping, jerking the RPM's were all over the place and at one point in the course of driving on the freeway it felt like it lost power and nearly stopped. This has been an ongoing problem since the purchase of the vehicle. It has been inspected and diagnosed by All Automatic. There were no warnings, messages or symptoms that were constant. It was sporadically slipping up until the time it gave out. I have spoke to several 2013 GMC Acadia owners who have the exact same problem along with the back light covers falling off and All the plastic coverings on the inside falling off.

I am writing to formally express my dissatisfaction regarding a significant safety and reliability issue with my 2020 GMC Denali. Specifically, the vehicle is experiencing premature wear and imminent failure of the front ball joints. I expect the suspension components of a premium Denali-trim vehicle to last significantly longer than the 37,061 miles currently on my odometer. Industry standards typically place the lifespan of these components between 70,000 and 150,000 miles. Technical Details of the Failure: The vehicle is currently exhibiting the following symptoms of accelerated ball joint degradation: •Excessive Vertical and Lateral Play: Inspection reveals play in the right lower ball joint that exceeds the manufacturer’s maximum allowable wear specifications. The left lower Ball Joint is starting to have a small amount of play, according to the technician

POST-RECALL 25V274 ( & EA25007, EA25001) EXHAUST INTRUSION WITH CARBON MONOXIDE POISONING HAZARD Following the complete engine replacement under GM recall N252494000, my vehicle has developed a severe and persistent exhaust intrusion that allows toxic exhaust fumes, including carbon monoxide (CO), to enter the passenger cabin. CO levels have measured a peak of 83 PPM and consistent reading between 20-37 over multiple tests. PATTERN OF POST-RECALL EXHAUST SYSTEM FAILURES Vehicle has been in for service 6 times, over 100 days, as part of the engine replacement plus (metal found in the oil pan). Since recall, the vehicle has had an exhaust smell and noise rattle issue with the following exhaust system components deemed failed and been replaced: 1. Radiator cap (leaking onto exhaust) 2. Exhaust muffler (replaced TWICE - June 2025 and August 2025) 3. Exhaust clamps (leaking) 4. Left exhaust manifold (warped) Critical Finding: Despite replacement of virtually the entire exhaust system, the defect persists. This suggests a fundamental design or installation defect related to the engine replacement procedure, NOT isolated component failures. Documented Carbon Monoxide Levels: Between January 30 and February 3, 2026, I conducted 15+ tests using a professional-grade Klein Tools ET180 Carbon Monoxide Meter. Results: • Peak reading: 83 PPM • Multiple readings: 40-72 PPM sustained for 6+ minutes directly at my [XXX] daughter's car seat position • Testing method: Vehicle started via remote start, CO meter placed in cabin, readings recorded over 10-15 minute periods Health Impacts to Family: • Wife and [XXX] daughter consistently experience dizziness, headaches, and nausea when riding in vehicle • Daughter now refuses to ride in vehicle because it makes her feel sick • Symptoms consistent with carbon monoxide poisoning Independent service station verification on January 30th confirmed "vehicle is dangerous to operate with children inside and needs immediate service." INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMA

My vehicle has been in 16 times since I bought it the most recent incident is for the engine which started about six months ago. It’s been in since then for other issues concurrently with this one it hesitates like it’s getting stuck in sand before it wants to go first the mechanic told me he didn’t sense it but the thermostat was stuck open so they fix that. Second time it went in they thought it was some sort of a filter and some other components I’m not sure. Again it was not fixed then my son and I were out in Minnesota freezing cold night in November and go and drive and then when again it was the drive train this time that got fixed a month ago about a week ago it starts making a noise like there’s too much snow in the tires. I get my car washed every few days but I got it washed again and that didn’t fix it so it’s in the shop again and I’m paying for a rental again. I have the Walser guard thank the Lord because it’s paid for itself about 15 times over. I’ve gotten two transmissions, an air conditioner, two sensors the arm that other people have complained about I don’t know exactly the name of it the trailer component that you plug into also blew out my seven way and I had to have my seven way wire fixed so I’m nervous about plugging that back in. My dad passed away and I spent $70,000 of my inheritance by this car. I should’ve flushed it down a toilet instead. Everybody makes fun at work that this car is literally gonna kill my kids and I because every other day it feels like we’re stuck on the side of the road.

I am driving a 2019 GMC Terrain SLT, and I have a serious concern regarding a recent service experience. On 02/10/2026, I had an oil change and a complete vehicle inspection performed at Kunes GMC Greenfield, Wisconsin. After the service was completed and I returned home, I noticed an unusual noise coming from under the engine hood. I immediately went back to the dealership and informed them of the issue. I was asked to return the following day (02/11) for further inspection. After their investigation, I was informed that the vacuum booster had failed. It appears that this issue was not identified during the original inspection, and I was the one who brought the noise to their attention. From my understanding, vacuum pump/booster issues are common with many 2019 GMC Terrain models. I am surprised that this has not resulted in a recall, especially considering the potential safety risks it poses to me and my family. What concerns me even more is that this issue was not detected during the dealership’s inspection. If it had worsened, it could have led to a serious safety situation. I had to spend $450 today to repair what appears to be a manufacturing-related defect. I respectfully request that this matter be escalated and that my claim for reimbursement be reviewed. I would appreciate your assistance in helping me pursue compensation for this expense.

This letter serves as a formal notice of concern and demand for accountability regarding the 2009 GMC Sierra LD, VIN [XXX] , owned by [XXX] . There are numerous documented complaints and safety investigations concerning premature tie rod failure in 2009 GMC Sierra models. While the 2009 model year may not have been subject to a sweeping, industry-wide recall specific to tie rods in the 1500 series, it is undeniably and consistently associated with premature steering component failure — including both inner and outer tie rods. The refusal to proactively address this defect, assign a broader recall, or take ownership of the recurring issue reflects a troubling disregard for consumer safety. Documented and Reported Issues Include: • Premature Wear: Tie rods becoming loose or failing between 50,000–100,000 miles, resulting in steering wander and excessive play in the steering wheel. • Clunking/Knocking Noises: Audible front-end knocking at low speeds, a well-known symptom of failing tie rod joints. • Severe Safety Risk: Instances where tie rods have separated or become dangerously compromised, directly affecting steering control. • Uneven Tire Wear: Excessive inner or outer tire edge wear caused by steering instability. • Recall 14V-246000: A related recall acknowledging improper tightening of tie rods where they thread into the steering gear rack — a defect that could cause separation and loss of steering control. The common symptoms — steering vibration, looseness, clunking when turning, and vehicle pulling due to misalignment — are not minor inconveniences. They represent serious safety hazards that endanger drivers, passengers, and the public. It is unacceptable for GMAC and General Motors to minimize or compartmentalize this issue when patterns clearly demonstrate a systemic steering component weakness in this model year. The presence of Recall 14V-246000 further demonstrates that the manufacturer was aware of tie rod-related risks ! INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5

Thermostat Issue (Steering Assist is Reduced Drive with Care) have changed this sensor 3 times in the past 3 years, there is no excuse for that. The emergency braking almost cause me and my daughter to be hit by a train when my car emergency braked while going over train tracks. this is unexcusable