6.8

fairly significant
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
9,502 miles

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problem #76

Feb 022026

Sierra 1500

  • miles
Vehicle is shifting hard when switching gears. Typical with the recall and the valve body being the issue. Dealership is saying it is not covered by recall.

- Santa Clarita , CA, USA

problem #75

Jan 302026

Sierra 1500

  • miles
On Friday, January 30, 2026 while driving our 2020 GMC Sierra 1500, we experienced sudden loss of power and the motor making a faint rattling noise. The motor soon after began making a horrible sound - - it was obvious something was very wrong. This vehicle only had 31,995 miles on it at the of the issue. We had the truck towed to the dealer the following day for evaluation. Upon inspection, it was determined that the #5 lifter had collapsed and the left bank of lifters needed to be replaced at an estimated cost of $4500. There were no warning lamps or alerts on our app for over 24 hours. Once at the dealer, we explained to the service advisor that our research concluded that GM is fully aware of these issues and that they are under investigation for possible recall. Our service advisor then made a call to GM who agreed to cover this repair under warranty (which we appreciate and feel was the right thing to do). However, after additional research, we are concerned that the right bank of lifters will fail next, or even worse, catastrophic engine failure that GM will refuse to cover. It is our understanding that NTSB is aware of these issues and is in the process of conducting an investigation. I would like to have our issue added to the investigation.

- Bakersfield, CA, USA

problem #74

Jan 022026

Sierra 1500

  • miles
My engine is projecting a ticking sound. Oil consumption is extreme.

- Oviedo , FL, USA

problem #73

Dec 082025

Sierra 1500

  • miles
My 2020 GMC Sierra 1500 experienced a premature transmission failure consistent with GM-??s known 8-speed transmission defect. My safety and the safety of others were put at risk if/when the transmission occurs a temporary lockup which can/will cause the vehicle to stall on the highway, and potentially create a minor/major automobile incident if vehicle stalls. The vehicle was taken to dealership Capital Chevrolet Montgomery, AL where dealership technician diagnosed/confirmed the issue along with pictures of internal transmission failed components as well as recommended resolution for fix. The vehicle has been inspected by my out-of-pocket expense extended warranty company Endurance Warranty Services sub-contracted repair claims adjuster. No warning lamps, vehicle messages, or other symptoms of the problem prior to the failure were noticeable; the vehicle had multiple diagnostic scans prior to original sale and after sale to present no issues or trouble scans. the first issue appeared or was noticeable 12/08/2025. GM has refused action by asserting warranty expiration despite widespread knowledge of this defect. The vehicle has been out of service since December 8, 2025.

- Montgomery, AL, USA

problem #72

Jan 062026

Sierra 1500

  • 146,000 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated that while his wife was driving at an undisclosed speed, the vehicle jerked violently. The driver stated that the vehicle failed to respond as intended while depressing the accelerator or brake pedal. The check engine warning light was illuminated. The driver was able to pull over to the side of the road. The vehicle stopped jerking while driving but failed to exceed 30 MPH. The driver pulled into a parking lot and parked the vehicle. The contact was made aware of the failure and went to the parking lot. The vehicle was restarted and jerked abnormally. Additionally, while shifted into reverse(R), the vehicle failed to function as intended. The vehicle was taken to the dealer, where it was diagnosed, and two DTC were retrieved for unknown transmission software failure, and it was determined an unknown part in the transmission had failed. The dealer informed the contact that an unstated recall was closed. The vehicle remained at the dealer unrepaired. The manufacturer was made aware of the failure, a claim was filed, and the contact was informed that the recall was closed. The failure mileage was approximately 146,000.

- Bakersfield, CA, USA

problem #71

Jan 052026

Sierra 1500

  • miles
I was driving my vehicle on the highway when the transmission suddenly gave out with no warning whatsoever. When I say gave out, I mean, it just completely stopped working and was unable to go into any gear. I was luckily able to coast over to the median without an accident occurring, but it was not without much concern or worry as traffic moving on the highway is 70 miles an hour plus and quite full of vehicles.I consider myself lucky that I have extensive driving experience and was able to conduct myself calmly under the circumstances. It was a bit tricky, getting situated though under those circumstances. There was no advanced warning in anyway. no engine lights, no sounds, nothing. This is a well maintained vehicle. All my service is done by the dealership, and I have never been given any indication that there was something wrong. However, After this happened, I have been researching and found that many of these vehicles with this transmission continue to have this problem. This is not normal wear and tear or normal mechanical failure. I have owned many vehicles and never felt as unsafe as I did in that moment, or had a vehicles transmission fail so abruptly.For me, and the research I have done, I can only hypothesize the materials and engineering involved with this transmission are inherently inferior, completely faulty, and a safety risk/hazard to anyone who owns or operates the vehicle. I consider myself lucky to walk away unscathed, other than the economic price that it is going to incur on my finances for repairs.I would hope that it doesn-??t take something serious to happen before someone takes action and conducts a recall of this product. From what I have read and what I have experienced, this is truly an unfortunate accident waiting to happen and it appears nothing is being done. I truly hope that you could take a little more look into this matter. Thank you for your time and energy. I have already contacted the manufacturer and felt ignored.

- Orlando, FL, USA

problem #70

Nov 142025

Sierra 1500

  • miles
My 2020 GMC Sierra with a 5.3L engine and 78,272 miles on the vehicle, experienced damaged lifters which also resulted in a damaged cam shaft. The total repair bill was $9,208.86. While in the GMC dealership for repair, there were 2 other trucks - same model, same year, same engine - in for the same repair. When searching on-line, I found the recall for the GMC 6.2L engine for similar issues. It is my opinion that the 5.3L engine is experiencing the same types of issues. I have driven GMC trucks for almost 40 years and have never experienced these types of issues. I have been told by several people that it is related to the Dynamic Fuel Management system and to fix the problem to disable the system to keep the truck in V8 mode. There are several solutions on line to make this happen. I am no engineer and only provide this as background information. From my perspective, it is clear that GM has a problem (whatever the root cause) with their 5.3L engines.

- Fenton, MI, USA

problem #69

Dec 142025

Sierra 1500

  • miles
While driving on the interstate at 70 mph, the transmission began to shudder. It continued the duration of the trip of 90 mins. Following day, the transmission is continuing to shudder and is now shifting hard.

- Foley, AL, USA

problem #68

Nov 092025

Sierra 1500

  • miles
My 2020 5.3 L GMC AT4 is experiencing loss of power with bucking & stalling. Cylinders are not activating when called check engine light is flashing, it starts rough and makes numerous noises at various speeds, as well as at idle. So I brought my vehicle to my local auto repair shop. Our mechanic found two failed fuel injectors and a failed throttle body. Then the loud knocks in my block failed an acoustic test. He also determined the lifters, push rods and camshaft are experiencing excessive wear. The afm system has failed! he warned me that further use of my motor (with only 42K miles on it) will cause a catastrophic failure. My research shows that these issues are becoming common of 5.3 GMC motors. We searched the country for a rebuilt motor and found that none are available for the next several months. However, I was able to find a new motor at much greater cost. GMC has declined assistance at this time. My vehicle has no value as is, so I ordered the new GM engine. Without the dod system, these engines were designed to go well over 100,000 miles. I am a faithful GMC owner and none of my previous GMC trucks (2003, 2013, 2015, 2019) had such a major problem. Now the 2020's fuel saving system has failed and requires repairs that amount to half the value of my truck. When a full size truck stalls on the highway it's certainly life threatening.

- Preston, CT, USA

problem #67

Oct 152025

Sierra 1500

  • miles
Ticking noise coming from engine slight metallic noise as well. RPMs drop and when they drop, you can feel power loss constant hunting in the RPMs. Also a weird vibration, not all the time in the front end somewhere.

- Mount Holly , NJ, USA

problem #66

Oct 132023

Sierra 1500

  • miles
-lifter failure on 6.2 v8 engine, causing damage to camshaft -lost significant propulsion while driving on the highway, nearly avoided being rear-ended by another vehicle due to loss of vehicle propulsion -dealer had to to replace lifter bank and camshaft -no issues, once lifter failed dash lights all lit

- Fort Hood, TX, USA

problem #65

Nov 122025

Sierra 1500

  • miles
My truck had engine failure while at the dealership getting new tires installed on 11/12/2025. When they started my truck they detected major knocking in my engine the 1st thing in the morning. It unsafe to drive they're telling me my engine needs to be replaced. My engine has 58,000 miles on it. There was no issues with my truck when I drop it off.

- Newark, DE, USA

problem #64

Nov 082025

Sierra 1500

  • miles
First my torque converter went out, no warning lights only shaking wehn shifting, I got it replaced already it cost me $2400 Second Warning light service for Brakes, Traction and power steering come on and off. And sometimes truck doesn't brake well and steering wheel feels hard to drive, it has happened while on expressway with family. Third Engine oil low Add oil warning sign comes up alot and I have to add oil, engine has a rough idle now, also when I turn truck on smoke comes out while having a rough idle, recently it started knocking, I haven't moved the truck since than

- Alamo, TX, USA

problem #63

Oct 062025

Sierra 1500

  • miles
Coolant control valve and engine cooling fan

- Vero Beach, FL, USA

problem #62

Sep 152025

Sierra 1500

  • 75,200 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated while driving approximately 40-60 MPH, the transmission hesitated while depressing the accelerator pedal. A dealer was contacted. The vehicle was taken to the dealer and was diagnosed with transmission control module (TCM) failure. The contact was informed that the TCM needed to be replaced. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 24V797000 (POWER TRAIN); however, the VIN was not included in the recall. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was 75,200.

- Delray Beach, FL, USA

problem #61

Sep 242025

Sierra 1500

  • miles
Constant engine issues, cams, lifters. Transmission problems. These engines in these vehicles need to be RECALLED. I have bought 6 of these trucks and all of them have the same issues. SPENDING 14k on new engines one after another is ridiculous. These are classified as -??work-?? trucks and can-??t handle -??working-???

- Winchester, VA, USA

problem #60

Sep 242025

Sierra 1500

  • miles
Constant engine issues, cams, lifters. Transmission problems. These engines in these vehicles need to be RECALLED. I have bought 6 of these trucks and all of them have the same issues. SPENDING 14k on new engines one after another is ridiculous. These are classified as -??work-?? trucks and can-??t handle -??working-??.

- Winchester, VA, USA

problem #59

Sep 242025

Sierra 1500

  • miles
Constant engine issues, cams, lifters. Transmission problems. These engines in these vehicles need to be RECALLED. I have bought 6 of these trucks and all of them have the same issues. SPENDING 14k on new engines one after another is ridiculous. These are classified as -??work-?? trucks and can-??t handle -??working-??

- Winchester , VA, USA

problem #58

Sep 052025

Sierra 1500

  • miles
2020 gmc sierra 1500 elevation 5.3l engine. Lifter failure due do faulty design I-??m afm/dfm systems.

- Dillonvale, OH, USA

problem #57

Mar 152025

Sierra 1500

  • 41,248 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at various speeds, the vehicle jerked abnormally while depressing the accelerator pedal. A dealer was contacted. The vehicle was taken to the dealer, and the technician informed the contact that the failure might be related to the engine or transmission; however, the contact was informed that the vehicle needed to be inspected to determine the cause of the failure. The vehicle was not repaired. The contact stated that the failure had occurred several times. The manufacturer was notified of the failure and informed the contact to file a complaint with the NHTSA Hotline. The approximate failure mileage was 41,248.

- Plymouth, MN, USA

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