2019 GMC Sierra 1500 Power Train

catastrophic engine failure to due connecting rod bearings spun on the crankshaft damaging the crank and sending bearing material throughout the oil galleries

While driving in traffic in March 2025, the vehicle experienced a sudden and complete engine failure, creating an unsafe condition. Subsequent diagnosis confirmed failure of the camshaft and lifters, requiring full engine replacement. General Motors declined to cover this repair. However, this failure is consistent with widely reported camshaft and lifter issues affecting other GMC and GM vehicles equipped with the same 6.2L engine platform. Due to the unavailability of replacement engines through GM, I was forced to wait several months for an engine sourced through Jasper Engines. During this time, the vehicle was inoperable, resulting in over $10,000 in out-of-pocket expenses, including extended rental vehicle costs. The engine replacement was completed by Camden Automotive and Diesel in Camden, South Carolina, who maintain all service and maintenance records related to this repair.

Catastrophic engine failure of known defective L87 engine

On 2/4/2026, my vehicle (2019 GMC Sierra AT4 and VIN # 3GTP9EED5KG240494) experienced a catastrophic failure of the engine oil cooler lines. This is a well-documented manufacturing defect involving the failure of the crimp joints between the rubber hose and metal tubing. This failure occurred abruptly, causing massive oil loss and posing a severe safety risk due to the potential for sudden loss of oil pressure and engine seizure while operating the vehicle at highway speeds. This specific component failure is recognized by General Motors under Customer Satisfaction Program (CSP) N212326940. GM explicitly acknowledged this failure as a manufacturing defect. Despite the fact that the defect is inherent to the part’s design—and not a result of typical "wear and tear"—GM has denied my request for reimbursement, citing that the vehicle is outside the standard 36,000-mile warranty period. I exhausted all good-faith efforts to resolve this through GMC’s internal escalation process. I spoke with a representative and a supervisor, both of whom refused to honor a reimbursement request based on the manufacturing defect. They refused to consider that the defect, as documented in GM’s own internal bulletins, is independent of mileage and that the repair was performed at an authorized GM dealership. I am seeking full reimbursement of $2,171.58 for the repair of a known, safety-related manufacturing defect. GM is failing to stand behind their "Professional Grade" standards by refusing to cover a part they have already admitted is defective. I request that your office mediate this dispute to facilitate a full refund of my out-of-pocket repair costs.

The contact owns a 2019 GMC Sierra 1500. The contact stated that in the first month that the vehicle was purchased, the vehicle intermittently hesitated before slamming into gear hard. No warning lights were illuminated. The vehicle was taken to the dealer, and the contact was informed that the manufacturer was aware of the failure and suggested that a triple fluid flush was needed, and the triple fluid flush was performed. The contact stated that the hard shifting persisted, especially while driving uphill. The vehicle was taken back to the dealer, where it was diagnosed and determined that the torque converter had failed and needed to be replaced. The vehicle was not repaired. The failure persisted, and the vehicle remained at the contact's parents' residence unrepaired. The manufacturer was not notified of the failure. The failure mileage was approximately 57,000.

The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the transmission unexpectedly hard downshifted. No warning lights were illuminated. The contact stated that the vehicle was hesitating while driving the rest of the drive. The vehicle was taken to the dealer; however, no cause for the failure was found. The dealer performed an 8-speed transmission fluid and filter replacement. The contact stated that the failure persisted. A month later, the contact stated that on a separate occasion, the transmission unexpectedly downshifted. No warning lights were illuminated. The vehicle was taken to the dealer; however, no cause for the failure was found. The contact stated that the failure persisted. The contact stated that a month later while her husband was driving on the freeway at an undisclosed speed, the engine seized and the rear-end locked and threw the driver into the steering wheel even though the seat belt was securely buckled. The contact stated that the transmission was stuck in drive(D), and the vehicle was unable to move forward. The driver shifted into reverse(R) and was able to pull off the freeway. The contact stated that the vehicle was then driven to an empty parking lot and left overnight. The vehicle was then picked up the following day and was driven to the dealer; however, no cause for the failure was found. The contact stated that the failure persisted. The manufacturer was notified of the failure. The contact hired a GMC engineer to inspect the vehicle and informed the engineer that the vehicle needed to be driven a minimum of three days and 300 miles before experiencing the failure. The contact stated that the engineer drove the vehicle for 100 miles. The contact stated that the GMC engineer and one of the employees at the dealer suggested replacing the PCM module because there was no fault code present during the failure. However, the contact was informed that there was no guarantee that replacing the PCM would fix the vehicle. The failure mileage was approximately 45,000.

Took truck to dealership for transmission issues such as hard shifts and shuttering on highway. Waiting 2 months for parts that didn’t fix the issue. Now waiting on another transmission which I’m being told is on back order!

The engine started making ticking sounds, then the check engine light came on on and it began running very rough. GMC dealer replaced camshaft, all 16 lifters and guides and one bent push rod. The repair (not including transportation - I had to leave in GallupNM when I was enroute to Minnesota) cost was $7,832.81. The vehicle has 93,000 miles

Transmission problem I have had 3 transmission replacement. I was told that these trucks have a faulty transmission from the sales representative to the mechanics. After these transmission replacement now I have an engine problem where the lifters need to be replaced and camshaft. I have had all service done on time never missed a service. Now the dealership is telling me that this could be a reason why my transmission keeps going out. And can’t really give me a reason why I keep having the same problem. Truck has 97k miles on it when I purchased it had 45k I can’t even enjoy the vehicle because it’s always at the dealership with the same problem and they don’t know why it’s keeps happening, at this point it is a safety concern for me this is my daily driver where I drive my kids to school now I never know when it will just stop running. It jerks I’m afraid when I’m stop at a stop sign I might hit the car I front of me.

Transmission has been failing for the life of this vehicle. Shuttered shifting and hard shifting are the norm. It is available for inspection. Vehicle does not shift properly when vehicle is in motion. Shifting is often delayed resulting in temporary loss of power. I have had the vehicle in to a transmission shop they have been able to reproduce the events. There are no warning lights visible to indicate an issue.

The contact owns a 2019 GMC Sierra 1500. The contact stated while driving 75 MPH, the vehicle occasionally downshifted or unintendedly came to a stop. There were no warning lights illuminated. The vehicle was taken to a dealer and the vehicle was diagnosed and the contact was informed that the transmission software needed to be updated. The vehicle was repaired; however, the failure persisted. The contact stated that on another occasion, the vehicle started to turn off unintendedly at traffic lights. The vehicle was taken to a different dealer and the vehicle was diagnosed and it was determined that the valve body software needed to be updated. The vehicle was repaired; however, the failure persisted. The contact stated that on another occasion, the vehicle started to vibrate violently while driving on the highway. The vehicle was taken to the original dealer and the dealer replaced the transmission; however, the failure persisted. The vehicle was taken to a different dealer and the vehicle was diagnosed with torque converter failure. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 48,000.

The contact owns a 2019 GMC Sierra 1500. The contact stated while driving at approximately 25 MPH, an abnormal sound was coming from under the floorboards. No warning light was illuminated. The contact had taken the vehicle to a local dealer, where it was diagnosed and determined that the transmission oil pump had failed and the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure. The failure mileage was approximately 158,000.

My truck is currently experiencing shuddering when driving. This happens at random times but is becoming more frequent. I have taken it into service shops on numerous occasions, and they have not been able to identify the cause due to my truck not exhibiting these conditions when they are diagnosing it. I have run out of funds to continually pay for diagnostic fees, so I have had to let it go until recently. Now it shudders, shifts very harshly, rpms fluctuate continuously, knocking noise when driving, and in the mornings when I first leave for work, my truck will not shift out of first without revving high in rpms. I took it to a mechanic and was told that it was my torque converter, which has now damaged my transmission. All of which I have to pay for out of pocket. These symptoms started when my vehicle was still under warranty (around 30,000 miles). I even flushed the transmission, and it did not help. This is my daily driving truck, and I use it to go to work and transport my 3 young children around. Most of our driving is done on the highway at high speeds (70 mph). When my truck shudders or shifts harshly, I feel that it is going to cause me to lose control or wreck, putting not only my life but my children's lives in danger. I have not consulted a lawyer, as I do not have enough money to do so. I have not had the manufacturer look at it, because when I called about it, they told me I would have to pay for all service fees since it is out of warranty. The only warning lamps I get is when it goes into limp mode (which is at least once or twice a month) and by the time I used to get it to a mechanic, the light was off and they said there is nothing they could do about it. All of this has been happening to some degree since it was around 30,000 miles and only getting worse. The fact that I have put over $20,000 into this (not including my monthly payments of $990) and now have to replace the transmission & torque converter is ridiculous.

I bought my 2019 GMC Sierra in August of 2019. It had 3000 miles when I bought it. It now has 59000 miles on it and is in the shop today for transmission repair. The authorized dealer has flushed the transmission and I am waiting for a call back. The flush will be in the $500+ range and they charge a $165 diagnostic fee also. The transmission shudders, knocks and grabs when I accelerate. It feels like I have been rear ended. It also leaps from a complete stop. It doesn't accelerate smoothly. I feel this is a dangerous situation. I have called GMC Customer Service to complain and they have escalated to someone who is going to call me back in 24-48 hours.

My truck has had two lifters fail at different times which ended up ruining the camshaft Now my truck feels like it’s going over a rumble strip on the highway at low rpm’s. During this speed the trans is slipping and can not pick a gear. Other gmcs had a service bulletine to change trans fluid but my did not. I have emailed twice to gm and have not heard anything back. I have close to 10000 in repairs and my truck has been down for 4 months.

Had to have transmission rebuilt found metal shavings and was shifting bad and shuttering. Vehicle Has 63,000 miles and is well maintained. Vehicle was taken to GMC but said their transmission person was on vacation for 2 weeks. Also parts dept Said they had no transmissions in stock and were back ordered. Truck was taken to AAMco and transmission was rebuilt And torque converter replaced . This is a common issue with GMC trucks.

The original engine (6.2L L87) had to be rebuilt by GM because of lower engine knocking in June 2024, with 57,873 miles. The rebuilt engine had to be replaced with a remanufactured engine in October 2024, but had to wait until the completed work in December 2024. The remanufactured engine started knocking, and that engine was replaced in October 2025. All part of the L87 6.2L engine failures. Problem documented by dealerships. Components were brought to GM's attention. No warning lights or messages - just lower engine knock.

The contact owns a 2019 GMC Sierra 1500. The contact stated while accelerating from a complete stop, the vehicle hesitated and the transmission experienced a hard shift to first gear. Additionally, the contact stated that the vehicle was shuddering while driving at slower speeds. There was no warning light illuminated. The vehicle was taken to the dealer but was not diagnosed or repaired. The manufacturer was notified of the failure and informed the contact that the VIN was not included in a related recall. The failure mileage was approximately 38,000.

Component/System that failed: The issue appears to originate from the transmission or drivetrain, specifically resulting in the rear wheels locking up and dragging at low speeds. It feels like something is seizing inside the drivetrain, making the truck very difficult to move. The vehicle is available for inspection upon request. How safety was put at risk: This failure presents a serious and unpredictable safety hazard. The vehicle begins locking up randomly when slowing down, such as in parking lots or residential areas. If this occurred at higher speeds or in traffic, it could easily result in a crash, loss of control, or pedestrian injury. It’s completely unreliable and unsafe to operate in this condition. Has the problem been reproduced or confirmed by a dealer or service center? The issue is part of a well-known transmission defect affecting GM’s 8-speed automatic transmissions. There are multiple class action lawsuits and thousands of consumer complaints documenting identical symptoms. GM is fully aware of the defect but has refused to issue a recall, instead allowing the time-based warranty to expire even when the mileage is still well within the 60,000-mile limit. My local GMC dealer refused to offer a loaner or goodwill repair and quoted over a week just to diagnose it despite knowing that this is a known failure point. The symptoms are consistent with the known defect GM continues to avoid addressing. Has it been inspected by the manufacturer, police, or insurance? No outside inspection has occurred yet. Given the widespread documentation of this defect and the consistency of symptoms, it should not be necessary to involve other parties. Were there any warning lamps or messages? No. There were no warning lights, messages, or alerts of any kind. The failure occurs randomly, and without any prior indication. That unpredictability makes the issue even more dangerous.

I was headed out of town and stopped in the neighborhood at a stop sign. As usual, the Auto Stop/Auto Start feature turned the engine off and when I lifted my foot off the brake pedal to reengage the engine, the truck started rolling backward. The engine would not start even though all the gauges and systems were working as if the engine was on. I had the truck towed to my mechanic and after troubleshooting, they determined the engine was locked up and would need to be totally replaced. My truck has the 6.2L gas engine and have since learned that GMC is recalling later model trucks with this engine in them due to engine failure. If my engine failure had happened anywhere other than at a stop sign in a neighborhood, it could have caused a significant accident. I can't find a new engine because of the GMC recall and the cost to replace the engine with a lower mileage, used engine is approximately $16,500.

I bought this vehicle at 80k miles and I have had an on going issue with the transmission. I have done research online and found that GM had put the wrong fluid in the transmission from the factory that has caused internal issues with the transmission leading to hard shifting and transmission shuttering. On my dime I have changed the fluid twice already and also the torque converter as well. This issue has gotten better but still a problem. This has caused me to not be able to trade my truck with out being upside down because of the dealers telling me they would have to put a new transmission to sell it. So now my trucks value has dropped as well. Now I am stuck in a truck that is not safe to drive. Thanks GM for not helping me.

Transmission hesitates. Transmission jerks when shifting. Possible torque conversion issues. Mileage is 35,623.

Transmission started fluttering around 60k miles. Per GMC Dealer - this is due to water getting into transmission from fluid put in at the factory. Even though dealer admitted that it's a defect from the factory, the warranty wouldn't cover the repair. This is a well known issue in the 5.3L 8 speed trans.

The contact owns a 2019 GMC Sierra 1500. The contact stated while driving at approximately 20 MPH and making a left turn, the vehicle shook violently. The contact stated that no warning light was illuminated. The contact stopped the vehicle and turned off, and restarted the vehicle. The vehicle was restarted, but after shifting into drive(D), and depressing the accelerator pedal, the vehicle failed to exceed 30 MPH. The contact stated that the vehicle was making an abnormal "roaring" sound. The contact stopped the vehicle and had the vehicle to be towed to the dealer. The dealer diagnosed the vehicle and determined that the valve body on the transmission needed to be replaced; however, the part to complete the repair was on a national back order. The vehicle was not repaired. The manufacturer was informed of the failure. The contact stated that the failure was the second transmission failure. The contact had the transmission replaced in 2024 by the same dealer. The failure mileage was approximately 84,000.

Transmission experiences shuddering while accelerating. Impact on driving performance which is a safety issue. Problem has been confirmed by the dealer. No warning lights are present during this problem.