The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at approximately 20 MPH, the vehicle lost motive power. The contact stated that the accelerator pedal was depressed; however, the vehicle failed to respond as needed. The contact moved the transmission lever from drive(D) to neutral(N) to reverse(R) several times and was able to drive back to the residence. The contact stated that the check engine warning light was illuminated. The contact had the vehicle towed to a local dealer. The dealer diagnosed the failure and determined that the transmission control valve had failed and needed to be replaced. The vehicle was repaired; however, the contact stated that the failure had reoccurred. The vehicle was taken back to the same dealer who advised that the transmission control valve had failed, but the parts needed to complete the repair were on back-order. The vehicle was not repaired. The contact had asked the dealer what the possibility of the same failure reoccurring after the second replacement of the control valve and the dealer advised that the valve would fail again. The vehicle was awaiting repair. The manufacturer was informed of the failure. The failure mileage was 27,676.

- Knoxville, TN, USA

The control valve system on my 2021 gmc has malfunctioned and this is the second time, currently sitting at Nelson GM Dealer in Fergus Falls MN. I have to drive back to TN as thats where I live and the mechanic said this issue will happen again. This vehicle hasn't had recalls but I believe it was missed since this is the second time with this same issue. This is a GM wide issue as I have researched.

- Knoxville, TN, USA

We had to replace the transmission at 70,000 miles even though problems were reported to the dealer at 53,340. This repair costed $2300 on a 1 year old truck. Then we needed to replace a solenoid circuit which was not covered under warranty. We repaired this 2x (the second time covered). Then at 147,000 miles 9/24, there was a cylinder misfire which bent the push rod and collapsed lifter. This engine repair cost $8300 dollars. Who has to replace an engine on a truck that's 3 years old. This is a defect. Please help us. We have spent over $10,000 on repairs. We faithfully do our changes and service.

- Sanbornton, NH, USA

L87 engine problems. I have had failed lifters, on top of transmission issues and a current oil consumption issue where I have to add two quarts of oil (sometimes more) without any indication of low oil. I took my vehicle into the local dealership and the technician asked if I had gotten any low oil indicator and I stated no. He proceeded to tell me it had little to no oil in it. Imagine this at highway speeds and sudden engine seizure.

- Spruce Pine, NC, USA

Transmission has a hard shift when coming out of each gear. 2nd to 1st shifts hard and jolts entire vehicle a head. Feels like a slip or difficulty in shift.

- Navajo, NM, USA

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at various speeds and downshifting, the rear wheels locked up with the parking brake warning light flashed on the instrument panel. The vehicle would resume normal operation soon after the failure. The vehicle was taken to a dealer where the contact was informed that there was a pending NHTSA Campaign Number: 24V797000 (Power Train) on the vehicle for the failure. The contact was informed that there was a temporary fix on the vehicle to repair the defect. After the temporary fix was performed, the contact experienced the failure twice within a week. The contact received a call that the permanent fix was available; however, soon after the repair was performed, the failure immediately occurred upon leaving the dealer. The manufacturer was notified of the failure, and the contact was informed that he would receive a callback. The vehicle was not repaired. The failure mileage was approximately 75,000.

- Goshen, OH, USA

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 24V797000 (POWER TRAIN); however, the part to do the recall repair was unavailable. The local dealer was contacted, and it was confirmed that the part was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The contact stated that the transmission was shifting hard while driving. The local dealer was notified of the failure. The cause of the failure was not yet determined. The manufacturer was not made aware of the issue. The failure mileage was 120,000. VIN tool confirms parts not available.

- Coeburn, VA, USA

transmission has a shudder when accelerating and after shifting through all gears (8speed) during cruise mode when going on an incline as in overpass it starts to shudder and seems like it is trying to find the right gear to go into.

- Grubbs, AR, USA

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The contact stated that the rear of the vehicle was shuddering and shaking. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The contact stated that over time the failure became more persistent. The contact was concerned because two small children were seated in the rear of the vehicle daily. The manufacturer was made aware of the failure but provided no assistance. The contact referenced NHTSA Campaign Number: 24V797000 (Power Train); however, the contact was informed that the VIN was not included in the recall. The failure mileage was approximately 61,000.

- Oakwood, GA, USA

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 24V797000 (Power Train); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer was contacted. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

- Houston, TX, USA

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at various speeds, there was a whining sound coming from the transmission. The vehicle was taken to the local dealer who diagnosed and determined that the transmission was faulty and needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure and informed the contact that the vehicle was not covered under the Extended Warranty for the failure. The failure mileage was 86,000.

- Pinedale, WY, USA

After having simple oil and filter, and engine and cabin filter replaced at Alpine Buick GMC in Colorado Springs, CO, I received my vehicle back and noticed a complete difference in performance. It hesitates when accelerating, stays low in every gear, and bounces, and I mean bounces hard, when shifting gears, especially slowing down. When slowing down, as it shifts to the next lower gear, it almost pushes the truck forward against me pushing the breaks. Then, when feathering to accelerate slowly, it almost bounces back up to speed, hesitating until I let off the accelerator pedal a little, and it immediately shifts to about 1000 rpm in gear. I have to push really hard for it to go up a gear, and when it does, it has lost all power. My vehicle doesn-??t run right anymore after my service appt. I have brought it to my hometown dealership and they say it runs fine and nothings wrong. But there is something wrong with it.

- Winter Haven, FL, USA

Transmission shifting is at times confused causing the vehicle to jump forward shifting to first gear. It pushes your vehicle 2-5 miles an hr faster when slowing down. The transmission also does the opposite when letting off the accelerator, shifting fast to a lower gear slowing the vehicle down quickly in a jerking motion at times. I have an 8 speed transmission. GMC dealer is replacing my torque converter, stating this may fix the issue, but it is a safety concern.

- Van Buren, AR, USA

1 June 2022, while driving, started hearing a clicking noise from front end, under hood. Took to local GM dealer, Mechanic drove with me, and he heard the noise, said he would order a part and safe to drive. So, I went home. 2 June 2022 started same vehicle, a very loud banging, clicking, shuttering noise from under hood, I took back to same dealer, Dealer said collapsed valve lifter. GM service notice says for dealer to fix under warranty. Apparently, a known problem with MANY 2021 GMC 5.3 L engines. PLEASE MAKE GM RECALL THIS ISSUE FOR REPAIRDS

- Jacksonville, AR, USA

8 lifters in my vehicle needed to be replaced. While driving my vehicle (12/4/21), after the auto stop feature was activated my truck experienced a lack of power and hesitation. I then turned the truck off and upon starting it was making a knocking noise. I immediately checked the oil as I wanted to make sure there was oil in the engine. I had warning lights on the dashboard and drove it about 3 miles to the dealer to be repaired. While driving it to the dealer, it did not sound right and shook. I also experienced a lack of power and was concerned for the vehicle to stall out while in traffic. The dealership informed me this is an issue with the 2021 GMC Sierra with a 5.3L V8 engine. I had seen online that GMC issued a service bulletin to have the lifters replaced in the 2021 GMC Sierra that were on the lot before they were sold (early December 2021). If this is a known issue why weren't the lifters replaced in vehicles on the road before the ones sitting on the lot. 8 lifters were replaced by the dealership but there was a shortage of parts due to the nationwide problem. There were no warning lamps, messages prior to the failure. The only symptoms I had was shaking and lack of power as indicated above after the autostop feature was activated. I then drove about 2 miles and went into a store before coming out and having the loud knocking on startup followed by warning lights and messages.

- Saegertown, PA, USA

When shifting into drive after reversing, truck will occasionally do a small thud and hesitate to move forward. This is from a stopped position after reversing, then braking, putting the truck into drive, then it happens when starting to move forward at very low speeds (I would say about 1-2mph). Vehicles recovers quickly, however it seems like a transmission mount or something may have issues. If another car were coming up quickly, or started going expecting you to start moving, the delay the thud and hesitation causes may be enough to cause a minor incident (assuming no high speed traffic coming up behind someone as they reversed out). This issue does NOT occur every time. I have owned the truck for 4 months, and it has happened only about 4-5 times in total.

- Lithia, FL, USA

Can turn vehicle off while in gear (drive specifically). When you let off the brake, the truck acts as if it is in neutral. Discovered in my driveway when accidentally forgot to shift into park when I pulled in and pushed the stop button. Truck turned off, which would only expect if in park (or neutral), let off brake, and it began quickly rolling backwards as if it was in neutral. Fortunately the brakes were working, but had any children been riding a bike on the sidewalk or walking by, my truck may have hit them. Had I been more distracted and not noticed initially, it could have rolled into the road and hit my neighbors truck. This behavior can be reproduced every single time, and I can easily supply video.

- Lithia, FL, USA

Prior to this incident I had lifter failure on my 2021GMC SierraAt 8464 miles, I was on my way to work and I heard a loud bang and I had to pullover off the highway, my dad had to come all the way out To get the vehicle because it had major engine damage and it was on a holiday so no one would come help me.The vehicle was in the shop for over a week getting these repairs done, upon receiving vehicle it had been a week and I received service four-wheel-drive messages on the dash.Trying to use four-wheel-drive after this was a no-go every time I push the button nothing would happen it would stay in two wheel drive.After this I made an appointment with the dealership for this issue to be fixed, as I was going to get readyTo leave again with the truck having no issues other than what I-??ve stated when I went to go start the truck nothing happened at all every light lit up on the dash and part of me thinks it-??s an electrical issue but the Other part of me thinks the motor is locked up. Also the lights would not shut off when I turn the vehicle off so I-??ll have a dead battery in the morning.

- Holly, MI, USA

THE CONTACT'S FATHER OWNS A 2021 GMC SIERRA 1500. THE CONTACT STATED THAT HER FATHER WAS DRIVING AT AN UNDISCLOSED SPEED, WHEN THE VEHICLE STALLED. THE VEHICLE STALLED THREE TIMES ON THREE SEPARATE OCCASIONS AND WAS TAKEN TO THREE DIFFERENT DEALERS. THE VEHICLE WAS FIRST TOWED TO Bill Kay Buick GMC (2300 Ogden Ave, Downers Grove, IL 60515) AND DIAGNOSED AS BATTERY FAILURE AND REPAIRED HOWEVER, THE FAILURE RECURRED. THE VEHICLE WAS THEN TOWED TO Phillips Chevrolet of Lansing (17730 Torrence Ave, Lansing, IL 60438) AND DIAGNOSED THAT THE TRANSMISSION CABLE CAUSED THE FAILURE. THE VEHICLE WAS REPAIRED HOWEVER, THE FAILURE RECURRED AFTER GETTING THE VEHICLE BACK FROM THE DEALER. THE VEHICLE WAS THEN DRIVEN TO Zeigler Buick GMC of Lincolnwood (6900 McCormick Blvd, Lincolnwood, IL 60712) BUT WAS NOT YET DIAGNOSED NOR REPAIRED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE AND A COMPLAINT WAS FILED. THE CONTACT WAS INFORMED THAT THE DEALER WANTED TO REPAIR THE VEHICLE. THE FAILURE MILEAGE WAS 3,000.

- Normal, IL, USA

Transmission shifts hard when shifting up and when downshifting. Vehicle jerks when going speeds <40 after coming off highway at highway speeds >70.

- Laneville, TX, USA