10.0

really awful
Crashes / Fires:
1 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
9,583 miles

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« Read the previous 20 complaints

problem #134

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 #133

Dec 172024

Sierra 1500

  • miles
This is a report on an incident that happened a year ago. Vehicle was taken to GMC dealer who replaced the engine at our expense. Seems to be consistent with the problem on newer GMC's that have been covered by a recall. This 2020 is one of three GMC's owned by our company. This expense was in the $12,000 range. (The 2019 experienced similar issues in 2022 and the expense was $2800 ish, and in 2024 another $1200 ish. ) Dash lit up like a Christmas tree, all warning lights on. Stalled, barely moved.

- Huntington, IN, USA

problem #132

Oct 122023

Sierra 1500

  • miles
Engine ticking especially when cold, dealership claims they fixed it while it was under warranty but it has continued to do it.

- Cooks, MI, USA

problem #131

May 012022

Sierra 1500

  • miles
At approximately 54,000 miles had a complete engine failure. Lifter blew apart and damaged crank shaft. Complete engine rebuild. Rebuilt in approximately 3 weeks. 2022 At approximately 138,000 miles had another complete engine failure. Lifter blew apart again, Entire engine was replaced. New engine took 10 weeks to get. Installed in 2 days after recieved. 2025 No symptoms or warning lights present prior to failure.

- Byron Center, MI, USA

problem #130

Nov 062025

Sierra 1500

  • miles
Engine knock, loss of power, engine failure warning, ticking

- Alpena, AR, USA

problem #129

Aug 222025

Sierra 1500

  • miles
While driving at highway speed and attempting to pass another vehicle, I experienced an engine failure; loss of power, noise from engine, and numerous warning messages on the display. At the GM dealer, I was informed that a pushrod (cylinder #2) was bent, the source of the engine noise. Upon further inspection (removal of cylinder heads), it was determined that the cam shaft chrome had begun to flake causing pitting (lobe damage) which in turn caused the pushrod to fail. Had the pushrod broke instead of bent at highway speed, I feel there would have been a catastrophic failure with more severe consequences for my vehicle and others around me. Vehicle was diagnosed and repaired by a certified GM dealer. There were no prior warnings/indications of problem(s). I understand there is a current recall of the GM 6.2L L87 engine for model years 2021-2024. This incident occurred on a model year 2020 GM 6.2L L87, but the issues I experienced are identical to the 2021-2024 engines identified in the recall.

- New Castle, PA, USA

problem #128

May 312025

Sierra 1500

  • miles
I experienced lifter and camshaft failure on my 2020 GMC Sierra equipped with the 6.2L V8 engine at approximately 72,000 km. GMC denied warranty coverage as my factory warranty had expired only four months earlier. The repair cost me nearly $10,000 out of pocket. My vehicle has been meticulously maintained with regular oil changes performed at my local GMC dealer every 5,000 km, and it has always been fueled with premium gasoline as recommended by the manufacturer. The engine failure was sudden and unexpected. All lifters and the camshaft were replaced during the repair. Since the repair, I have noticed intermittent RPM fluctuation under light load conditions. I am currently working with my dealer to diagnose whether this issue is related to the recent engine repair or a transmission flush that was performed at the same time. I am extremely disappointed in GMC-??s handling of this situation. Despite this being a well-documented issue with the 6.2L engine, I received no goodwill assistance or warranty consideration from GMC. While my dealer provided a partial discount on parts and labor, I was still responsible for nearly the entire repair cost. I hope GMC and NHTSA will review this matter closely, as owners should not be facing such expensive failures on well-maintained vehicles with this engine.

- Lacombe, AL, USA

problem #127

Oct 142025

Sierra 1500

  • miles
A lifter in my cylinder is bad and damage to my cam shaft. This truck also has the 6.2L engine that was recalled for other GMC Vehicles.My safety was put at risk as I was driving it and it started smoking. I have had 2 different mechanics look at it. One mechanic was an independent business, the other was a certified GMC dealer. There was no warning lamps or messages.

- Cedar Rapids, IA, USA

problem #126

Aug 282021

Sierra 1500

  • miles
Rod bearings spun and engine locked up while driving 70mph on the freeway. I was in traffic, and had to work my way over and off to the shoulder of the road. The engine was diagnosed and replaced by Hiley GMC at a cost of nearly $5,000 out of my pocket. This was at approximately 63,000 miles. Just out of warranty. No loaner vehicle provided. I was without my truck for 2 months. There were no warnings at all. No lights or noises of any kind. Rod bearings spun again on the replacement engine approximately 35,000 mile later. It happened same as before. Driving on the freeway at 70mph, and the engine seized. No power steering, no warning noises or lights. I had to coast across lanes through traffic and onto the shoulder. Diagnosed and replaced by Jerry's GMC. They replaced the motor at no charge except I had to provide the new radiator because it was on backorder. They had the truck for over 3 months and I had no loaner vehicle. With approximately 65,000 miles on the latest engine, a lifter went out. I put it in the shop to have all the lifters replaced, and motor mounts replaced at a cost of $6500. Upon taking the truck for a test drive, the engine seized in traffic under an overpass and blocked one lane of traffic. The shop dropped the oil pan to check it out, and, lo and behold, this engine has spun rod bearings again. There is definitely a serious and dangerous problem with the L87 6.2L. Being a 2020, it is not currently included in the recall, but it needs to be included. I spun bearings the first time in August of 2021. I was hoping it was just bad luck. I hadn't heard of all the instances at the time. I've never had a major engine failure prior to this model, and this one has failed 3 times in the same truck with meticulous maintenance.

- Fort Worth, TX, USA

problem #125

Oct 282021

Sierra 1500

  • 19,000 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving 55 MPH, the vehicle failed to accelerate as intended while depressing the accelerator pedal. In addition, there was an abnormal sound coming from the engine. Multiple warning lights were illuminated. The contact was able to coast to the side of the road. The vehicle was towed to the dealer, where it was diagnosed with engine failure. The engine was repaired. Most recently, while driving 35 MPH, the vehicle failed to accelerate as intended while depressing the accelerator pedal, with an abnormal sound coming from the engine. Multiple warning lights were illuminated. The vehicle was towed to the dealer, where it was diagnosed with engine failure. The contact was informed that the camshaft, bearings, and lifters in cylinder #4 had failed. The vehicle remained at the dealer unrepaired. The manufacturer was notified of the failure. However, no assistance was provided. The failure mileage was approximately 19,000.

- Inwood, WV, USA

problem #124

Oct 092025

Sierra 1500

  • miles
The check engine light went off and started blinking. The engine started making ticking noise. I pulled over. The check engine light kept blinking. I had the truck towed to the Chevy Dealership. They found damage to the lifter and camshaft. They had the truck for over 2 weeks. Luckily I purchased the extended warranty. But the repair still cost me $1,200 dollars out of pocket. And cost the warranty company over $9,000 dollars

- Romeo, MI, USA

problem #123

Sep 092025

Sierra 1500

  • miles
I heard a ticking noise coming from the engine compartment. I took it to the dealership that I purchased the truck from and that have been using consistently for service. I was told that the noise was coming from a lifter on the driver's side of the engine and, on further investigation, it was determined that the camshaft had been damaged. I was told that it could seize up as I was driving and that my safety and those with and around me would be at risk. At 85,000 miles, the engine had failed and would have to be replaced. There was no prior warning or no check engine light and the vehicle has been in for oil changes and all maintenance at the dealership. The new engine cost me $15000 including diagnosis and towing.

- Nashville, TN, USA

problem #122

Oct 152025

Sierra 1500

  • miles
I noticed a ticking sound in my 2020 GMC Sierra 1500 SLT 5.3 Liter on 10/15/2025 after it was serviced at an Authorize Buick GMC Dealership on 10/13/2025. I made an appointment and returned the vehicle to the dealership for further inspection on 10/17/2025. I was informed later that day that my truck has lifters and camshaft failure. If my truck had stalled or stopped on the express way, myself and others safety could have been at risk. My truck has only been looked at by the dealership at this time, and it is available for inspection upon request. There were no warning lights, check engine lights, messages or symptoms prior to the failure. I did get a low oil level message in April 2024 when the dealership stated they must not have put the correct amount of oil in my truck during an oil change on 1/29/2024. They inspected my truck and assured me there was no damage done to my Engine from this issue. I have recently learned there is a recall for GM Vehicles manufactured between 2021 and 2024 with the 6.2L engine installed. I am not sure why this recall does not include 2020 trucks with the 5.3L engines installed. Apparently, the same problems exist with these engines also. I received an estimate for repair approximately $13,000 which can increase once the engine is town down and inspected further. Any assistance you can provide would be greatly appreciated.

- Collierville, TN, USA

problem #121

Sep 082025

Sierra 1500

  • miles
The engine failed completely while driving. On the day of the incident, I started my 2020 GMC Sierra 1500 AT4, and immediately upon cranking, the engine began knocking loudly. I shut the vehicle off right away to prevent further damage and called a wrecker service to have it towed to Marianna Chevrolet, GMC. No warning lights or messages prior to the incident. The weather was clear and dry, and the truck was parked on level ground at the time. There were no prior warning lights, leaks, or unusual noises before this event. The vehicle has been well-maintained, with oil changes performed regularly every 4,000 miles at a local auto shop (though receipts are not available). The brakes were replaced earlier in 2025. Marianna Chevrolet, GMC inspected the vehicle and estimated the repair cost at $12,700 due to what appears to be a major internal engine failure.

- Wewahitchka, FL, USA

problem #120

Oct 122025

Sierra 1500

  • miles
43000 miles 2020 gmc sierra with lifter engine issues. Oil change made every 3k miles

- San Luis, AZ, USA

problem #119

Sep 272025

Sierra 1500

  • miles
6.2L V8 engine in 2020 GMC Sierra 1500 AT4 suffered two lifter failures, which damaged crankshaft and sent metal shards throughout engine and oil. Total engine replacement required. This issue is subject to a recall for 2021 - 2024 model years and the recall should extend to 2020 model years. Vehicle was traded without functioning engine at a significant loss in value for new vehicle, and is not available for inspection. Vehicle was inspected by service department at GMC dealership and traded to a different GMC dealer. No prior indications of problems or warning lights until engine failure occurred while driving.

- Chesterfield, MO, USA

problem #118

Sep 082025

Sierra 1500

  • miles
Engine misfiring and rough idle with occasional flashing engine light. Dealer said no codes to know what to look for despite replicating issue. Eventually it threw a Cylinder 5 misfire and thus GM dealer was able to look further. They found metal in oil pan and concluded a bearing issue and would need to replace engine.

- Parsippany, NJ, USA

problem #117

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 #116

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 #115

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

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