2023 GMC Sierra 1500: engine knocking or ticking

Filed Oct 29, 2026 · Engine · AL

My 6.2 motor in my 2023 GMC AT4 truck has blown up. As part of the recall that GM has on this motor it passed the "pico test" at around 50k miles or so ( I can provide the paperwork) and then this past week with 63k miles or so the engine developed a miss and eventually by the time I got it to the dealer there was a significant "engine knock". The service center called the next day and said there was definitely a engine failure and I was lucky to have made it to the dealer. The vehicle is at the dealer waiting on a new engine. I was quoted 2 weeks but we are passing that time frame now. GM needs to be held accountable for this mess.

Filed Oct 21, 2026 · TX

The engine was part of the initial recall for the L87 GM motor and failed its inspection. Ultimately the engine had to be replaced. Since, the engine was replaced everything was fine till recently it starting to make a knocking noise and was immediately taken to a GM dealership for diagnosis. Currently, waiting for final decision on the fix, but preliminary the dealership stating its the lifters or camshaft.

Filed Oct 16, 2026 · Engine · MI

A 6.2 engine operated as expected for 75,000 miles. I turned a corner at an intersection, and had a loud knocking in the engine occur. For the first 75,000 miles, there wasn't any unusual engine noises or oil consumption.Seconds later the engine light illuminated on the dash, reduced engine power, and every safety light within the dash was going on and off. I managed to drive slow and return to my residence and have the truck towed to the dealership to have the engine replaced. As many have learned, the recall from GM states to either pass a PICO test and change to 0W-40, or have the engine replaced if necessary. My concern is that the replacement engine is the exact same engine with the exact same components that assuredly will fail due improper design, production, and overlooked components that attribute to such failure. The crankshafts are being found to have values of "peaks and troughs" within the finish that are many times out of given specifications. The extraneous pressures created by the Dynamic Fuel management system over time are creating stresses and friction that the designated oil and oil pump are not compensating for. These mechanical stresses over different durations, seem to be part of the cause of the engines failure. The replacement engine came with a warranty that only extends to an odometer reading of 150,000 miles. I no longer have confidence in a manufacturer that is enforcing false resolve upon a customer as a solution. The new engines of replacement have been failing as well. This result exhibits a fact that shouldn't be ignored. The new engines have the same components and are due to fail, just the same as the original. I would like the manufacturer to resolve this failure by offering a "true" solution. A proven remedy and a documented warranty that assures the manufacturer stands behind the product. GM sells a new product that fails and then recalls the engines to replace with the same failed components and lack of warranty.

Filed Sep 16, 2026 · Engine · TN

On 9-10-26 Engine spun rod bearings per the dealership repair order Miles 52,796 I was towing a car on a car trailer traveling down the interstate when the motor failed. I had my wife in the truck with me. No prior warnings just a check engine light right before engine failed. GMC dealer replaced engine and returned on 9-14-26. The truck had already had the recall to check the engine and replace the oil to a thicker oil.

Filed Sep 9, 2026 · Engine · 12,998 miles · TX

The contact owns a 2023 GMC Sierra 1500. The contact stated that while driving 65 MPH, the engine made a clunking, knocking, and tapping sound. The engine was driving on seven of the eight cylinders. The contact slowed down and pulled over. The engine warning light was illuminated. The vehicle was taken to the local dealer and was diagnosed with a detached valve. The vehicle was repaired under an extended warranty. The dealer informed the contact that the failure might recur. The failure mileage was approximately 12,998.

Filed Sep 2, 2026 · Engine, Transmission · PA

I am reporting a serious safety concern involving a 2023 GMC Sierra 1500 Denali, 6.2L L87 V8, VIN [XXX]. This vehicle has now experienced two catastrophic powertrain failures at very low mileage. The first catastrophic engine failure occurred at approximately 23,696 miles. The vehicle was taken to a GMC dealer, where the repair documentation states that the engine had suffered significant internal damage, including damage to the #3 connecting rod, a missing connecting-rod bearing, bearing material throughout the engine, and a scored crankshaft. The dealer determined that the engine was seized and required replacement. GM replaced the engine under warranty with GM engine assembly part number 12740076. The vehicle has now experienced a second catastrophic failure. On [XXX], while traveling approximately 40 mph, experienced grinding, lurching, and knocking, followed by a complete loss of propulsion. The truck would no longer move and had to be towed to a GMC dealer. At the time of the incident, no warning lights or warning messages were observed. The transmission is also suspected to have failed, although the exact cause and extent of the transmission failure have not yet been determined by the dealer. I understand that the federal safety agency is currently investigating failures involving GM 6.2L L87 engines, including failures occurring after previous recall remedies and engine replacements. I am therefore requesting that this incident be included in the federal safety agency’s investigation and considered when evaluating the effectiveness of the existing recall remedy and the safety of replacement L87 engines. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 1, 2026 · Engine, Fuel system · CA

I am reaching out to the federal safety agency due to a vehicle that I believe will get me and/or my family in a major accident and cause serious injury or death. The vehicle that I had purchased in 07/08/2025 had a clean history report and was bought at 54,587 miles. It started having issues 8,563 miles later (odometer reading 63,150 ) on a trip that was 400 miles round trip. I was driving the vehicle on a highway at 65 mph and i felt a knocking vibration in the pedal it was not long before i could even pull over when the engine throttle had completely lost power causing the vehicle to almost come to a complete stop immediately having to steer onto the shoulder. after failing with no check engine light or warning present during the use of the vehicle on the road. it was giving off high temp/engine overheating with the engine making a continuous knocking sound in the engine. It eventually seized to work completely not being able to shift into neutral to push, and had to get it towed to the dealership 204 miles away. GM had advised the dealership to replace the whole engine which they did, and that second engine had given out 678 miles later (odometer reading 63,828.) I am now on my THIRD engine and i cannot trust or rely this vehicle for saftey or transporation. i have reached out to GM to file a claim and attempt to adress this issue to try and come to a resolution, however they denied my claim and have said that i am not "eligible" for a buyback program. I am considering getting legal attorney this is very frustrating to say the least GM is a terrible manufacturer for this issue

Filed Jul 25, 2026 · Transmission · WI

While towing my trailer the vehicle intermittently slams gears and will hesitate the back tires momentarily to the point of screeching. This has led to close calls being nearly rear ended and having to pull over. This started out as a hard slam while trailering on the highway and has progressively gotten worse. Had into dealership twice to multiple times to try and figure out the issue but it’s not throwing any codes and they can’t get it to duplicate the issues. Nothing can be replaced due to no codes even though they think the valve body is going bad. Leaving the vehicle as a ticking time bomb for failure which could result potentially in a catastrophic incident. Only had the vehicle for one year now has 37k miles on it and have had the ecm, full wiring harness, and multiple sensors replaced already for a different problem early this year that had the truck in the shop for a month.

Filed Jul 23, 2026 · Engine · KY

Complete engine failure while driving on a highway. While cruise was set, the truck emitted a sound and sensation like we had run over something on the highway. Within a few minutes the engine started ticking. The cruise was disengaged which thru the truck into neutral. No dashboard sensors were illuminated. We were able to get off the highway but the truck would not restart. Truck was towed to nearest dealer who has confirmed engine failure.

Filed Jul 10, 2026 · Engine · 17,000 miles · CT

The contact owns a 2023 GMC Sierra 1500. The contact stated that while operating the vehicle, there was an engine knock at start-up, and the engine intermittently hesitated and skipped. The vehicle was taken to the local dealer, who performed a PICO test on the engine, and the engine passed. Later, while hauling a trailer, there was a rattling sound coming from the engine. The vehicle was taken back to the dealer, who diagnosed the vehicle and determined that the engine needed to be replaced. The engine, radiator, and oil cooler were replaced, and the vehicle was repaired. The manufacturer was notified of the failure. The failure mileage was 17,000.

Filed Jul 2, 2026 · Engine · CA

While driving vehicle on state highway exit at approximately 55 mph a knocking noise started coming from engine then engine just died and would not restart. Engine was replaced under recall.

Filed Jun 29, 2026 · Engine · CT

Engine knocking. Engine being replaced under warranty due to premature bearing failure. Picotest was performed prior to my purchase with 12800 miles. 0w40 oil being used at the time of failure. At the dealer now getting the engine replaced.