2020 GMC Sierra 1500
Problems, recalls and owner-reported issues
Engine is the leading concern among 468 owner complaints filed for this model year. This is the 7th highest complaint count among 26 Sierra 1500 model years with reports.
Of the 2020 reports, 12 involved a crash and 5 involved a fire. 13 people were injured.
What owners report most often
Recalls and investigations
Power train, automatic transmission, control module, softwareFeb 12, 2026
General Motors, LLC is recalling certain 2020 Chevrolet Silverado 2500, 3500, GMC Sierra 2500, 3500, and 2020-2022 Chevrolet Silverado 1500 and GMC Sierra 1500 vehicles that may have been repaired incorrectly under recall 24V797. The transmission control valve may fail and cause the rear wheels to lock up.
Rear wheel lock up increases the risk of a crash.
Dealers will inspect the vehicles and update the transmission control software, free of charge. Owner notification letters were mailed March 6, 2026. Owners may contact GMC customer service at 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N252516560. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on February 12, 2026.
Campaign 26V083000 on NHTSA.gov
Power train, automatic transmission, control module, softwareOct 24, 2024
General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.
Rear wheel lock-up can increase the risk of a crash.
Dealers will install new transmission control module software, free of charge. GM will provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a defective control valve. Owner notification letters were mailed December 12, 2024. Owners may contact GM customer service at 1-888-988-7267, Cadillac customer service at 1-800-458-8006, GMC customer service at GMC 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N242454440.
Campaign 24V797000 on NHTSA.gov
Tires, temporary/emergency spare tireDec 16, 2021
General Motors (GM) is recalling certain 2019-2021 GMC Sierra 1500 and Silverado 1500 vehicles equipped with certain accessory road tires and a 17" spare tire. The 17" spare tire provided with the vehicle is not compatible for use with the accessory wheels, which can cause the anti-lock brake system (ABS) to not function properly under certain conditions.
An ABS system that does not function properly can increase the risk of a crash.
Dealers will provide a new 17" spare tire and wheel assembly that is compatible with the accessory wheels, free of charge. Dealers will also apply a new spare tire information label, and provide owners with an owner's manual insert clarifying which spare tire to use with the accessory road tires and with the 17" original tires. Owner notification letters were mailed February 7, 2022. Owners may contact GM customer service at 1-800-462-8782 or GMC customer service at 1-800-462-8782. GM's number for this recall is N212346510.
Campaign 21V985000 on NHTSA.gov
TiresFeb 25, 2021
General Motors LLC (GM) is recalling certain 2020 Buick Enclave, Cadillac XT4, XT5, Escalade, Escalade ESV, Chevrolet Suburban, Tahoe, Traverse, GMC Yukon, Yukon XL, 2018-2021 Chevrolet Express, GMC Savana, 2019-2020 Chevrolet Blazer, Silverado 1500, GMC Acadia, Sierra 1500, and certain Continental tires sold to the aftermarket for various model year 2018-2021 vehicles. The affected tires were cured for too long during production.
Over cured tires may develop a break in the sidewall resulting in sudden air loss or a belt edge separation which could lead to a tread/belt loss. Either condition can cause a loss of vehicle control, increasing the risk of a crash.
GM will notify owners, and dealers will inspect the tires, replacing them as necessary, free of charge. The recall began March 22, 2021. Owners may contact GMC customer service at 1-888-988-7267, Buick customer service at 1-866-608-8080, Chevrolet customer service at 1-800-222-1020 or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N212329050.
Campaign 21V115000 on NHTSA.gov
Seat beltsDec 17, 2020
General Motors, LLC (GM) is recalling certain 2019-2021 Chevrolet Silverado 1500 and GMC Sierra 1500, 2021 Chevrolet Suburban and Tahoe and GMC Yukon XL and 2020-2021 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles. The seat belt brackets may not be secured to the seat frame in the front-row center seating position.
If a seat-belt bracket is not secured, the seat belt may not properly restrain an occupant in the front-row center seat position, increasing the risk of injury in a crash.
GM will notify owners, and dealers will inspect left-side and right-side front-row center seat-belt bracket attachments and reassemble it correctly as necessary, free of charge. The recall began January 26, 2021. Owners may contact GMC customer service at 1-800-462-8782, Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202314670.
Campaign 20V792000 on NHTSA.gov
TiresNov 5, 2020
General Motors LLC (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5, GMC Acadia and Chevrolet Traverse vehicles and 2020-2021 Chevrolet Silverado 1500, GMC Sierra 1500 vehicles. The vehicles may have been manufactured with Continental tires that were overcured.
Overcured tires may experience a carcass break in the sidewall resulting in a sudden air loss or could develop a belt edge separation which could lead to partial or full tread/belt loss. Either condition increases the risk of a crash.
GM will notify owners, and dealers will inspect vehicles and replace tires that have DOT number and production mold number combinations identified by Continental, free of charge. The recall began December 17, 2020. Owners may contact GMC customer service at 1-888-988-7267, Buick customer service at 1-866-608-8080, Chevrolet customer service at 1-800-222-1020 or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N202319030.
Campaign 20V684000 on NHTSA.gov
Power train, driveline, driveshaftOct 22, 2020
General Motors LLC (GM) is recalling certain 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500 and 2020 Chevrolet Silverado 2500 trucks. One of the driveshaft joints may not have been properly welded, causing the driveshaft to separate while the vehicle is moving.
If the driveshaft separates, there may be a loss of propulsion, increasing the risk of crash.
GM will notify owners, and dealers will replace the driveshaft, free of charge. The recall is expected to begin December 2020. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-888-988-7267. GM's number for this recall is N202314870.
Campaign 20V650000 on NHTSA.gov
Air bags, side/window, curtain, inflatorJul 30, 2020
General Motors, LLC. (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5 and XT6, Chevrolet Blazer, Silverado 1500, 2500 and 3500 and Traverse and GMC Acadia and Sierra 1500, 2500 and 3500 vehicles. The diffuser component of the Roof-Rail Air Bag (RRAB) inflator may not have been properly crimped to the inflator and could separate from the inflator during air bag deployment.
If the diffuser separates from the inflator during deployment, RRAB performance may be degraded, increasing the risk of injury in a crash.
GM will notify owners, and dealers will replace the suspect RRAB modules, free of charge. The recall began September 3, 2020. Owners may contact Chevrolet customer service at 1-800-630-2438, Cadillac customer service at 1-800-333-4223, or Buick customer service at 1-800-521-7300. GM's number for this recall is N202305380.
Campaign 20V446000 on NHTSA.gov
Service brakes, hydraulic, foundation components, disc, caliperFeb 27, 2020
General Motors LLC (GM) is recalling certain 2020 Chevrolet Silverado 1500 and GMC Sierra 1500 vehicles. The bolts used to attach the front and/or rear brake calipers may have not been heat treated and may break under load.
Broken caliper bolts can reduce brake performance or interfere with wheel rotation and increase the risk of a crash.
GM will notify owners, and dealers will replace the brake caliper bolts, free of charge. The recall began March 23, 2020. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-866-522-9559. GM's number for this recall is N202294420.
Campaign 20V116000 on NHTSA.gov
Electrical system, 12v/24v/48v battery, cablesDec 12, 2019
General Motors LLC (GM) is recalling certain 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500 trucks. The battery positive (B+) cable rings may have been manufactured with excessive glue, potentially causing an intermittent electrical connection between the B+ cable and alternator.
An intermittent electrical connection between the B+ battery cable and the alternator could cause the vehicle to stall, increasing the risk of a crash. The intermittent connection could also lead to electrical arcing, which could generate sufficient heat to damage surrounding material, increasing the risk of a fire.
GM will notify owners, and dealers will inspect for the presence of glue or other contamination at the B+ cable attachment to the alternator and clean the connection and reattach the B+ cable connection, as necessary. If arcing has damaged the cable, nut, or alternator, the dealer will replace the damaged components. All services will be performed free of charge. GM issued owners an interim notification on February 4, 2020. GM issued second notice and the recall began March 9, 2019. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-888-988-7267. GM's number for this recall is N192273510.
Campaign 19V888000 on NHTSA.gov
Fuel system, gasoline, delivery, fuel pumpNov 21, 2019
General Motors LLC (GM) is recalling certain 2020 Cadillac Escalade, Escalade ESV, Chevrolet Camaro, Silverado 1500, Suburban, Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles. The fuel pump may be missing a pressure regulator, allowing for over-pressurization of the fuel system.
Over-pressurization can crack the fuel pump and cause leaks, increasing the risk of a fire in the presence of an ignition source.
GM will notify owners, and dealers will replace the fuel pump, free of charge. The recall began December 18, 2019. Owners may contact Cadillac customer service at 1-800-333-4223, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-888-988-7267. GM's number for this recall is N192283991.
Campaign 19V837000 on NHTSA.gov
Seat belts, pretensionerNov 14, 2019
General Motors LLC (GM) is recalling certain 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500, and 2020 Silverado 2500, Silverado 3500, Sierra 2500, and Sierra 3500 vehicles equipped with carpet floor covering. When the front seat belt pretensioners deploy, hot gas may vent through an opening in the pretensioner bracket, possibly igniting the carpet.
A vehicle fire could result if materials ignite inside the vehicle.
GM will notify owners, and dealers will close off the opening in the pretensioner bracket, free of charge. The recall began December 13, 2019. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-888-988-7267. GM's number for this recall is N192270600.
Campaign 19V814000 on NHTSA.gov
Representative owner complaints: electrical system
80 reports, newest first. Show all
Electrical system, Engine, Sep 28, 2026
6 months after owning it the lifters went bad got them Fixed then they immediately went bad again also bent rods then a day after getting that fixed again the oil pump went bad it was issue after issue
Power train, Electrical system, Engine, Sep 15, 2026
5/5/25 woke up back seat entire truck flooring soaking wet back glass cracked. 4/8/25 transmission went out 117,000 miles 7/3/25 exhaust leak and placed nox 1. 7/8/25 127551 mileage exhaust leak replace gaskets, belt , tensioner, and pulley, 6/8/2025 3 knock sensors replaced and replaced intake manifold.
Power train, Electrical system, Engine, Aug 24, 2026
Our 2020 GMC SIERRA 1500 has suffered catastrophic systems and engine failure including the brakes multiple times for almost 4 years. It has happened in high traffic and on the interstate each time having to be coasted off of the road to come to a rolling stop. There have been nine repair attempts with GM dealers repeatedly stating the issues were repaired and returning our vehicle to us. We began making the CEO and Executive team aware of the potentially deadly safety hazards including the fact that I, [XXX] am disabled and power wheelchair dependent requiring a truck that can carry my power wheelchair. We have sent numerous emails to Ms. [XXX] and the Executive team numerous times informing them in detail, each time, of all issues involved. We started communicating via phone and email with customer care to no avail. All attempts at repair finally ended in complete engine failure leaving us with an estimate to replace the engine of over $13,000. We have also, submitted a detailed complaint to the Attorney General’s Office and after review were given the Case # TCP - XXX. I will attach the Complaint and Addendum sent to the Attorney General along with two of the emails sent to Ms. [XXX] and her team informing her of all issues with the truck. They took no action to actually help us get this truck off of the road knowing it was having catastrophic engine and system failure and that it had to be driven to transport a disabled power wheel dependent with severe medical issues and the medically necessary power wheelchair. I am also attaching the earliest OnStar Diagnostic notice of Engine, Transmission and Emissions system issues from May of 2023. The issues have remained the same from the beginning only worsening though my husband has only driven the truck in town on slower less busy streets learning how to make adjustments such as pumping the brakes and starting and stopping the truck to keep it going. My carrier is installed and yet it is undrivable. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Steering, Electrical system, Engine, Jun 8, 2026
- THE GROUND STRAP CORRODED AND BROKE APART. YES, I HAVE THE GROUND CABLE THAT FAILED, IF NEEDED FOR INSPECTION. - YES!!! THE TRUCK'S STEERING KEPT GOING IN AND OUT OF MANUAL STEERING AND THE ENGINE REDUCED IN SPEED ALLOWED, AND THEN THE ENGINE CUT OUT ON ME COMPLETELY - WHILE I WAS IN THE MIDDLE OF A BUSY ROAD TRYING TO TURN ONTO A SIDE STREET. THEN THE ENGINE WOULD NOT RESTART. - I HAD THE TRUCK TOWED ON A FLAT BED TO A GMC DEALERSHIP NEARBY. THEY CONFIRMED THE ISSUE WAS THAT THE GROUND STRAP FAILED. THEY REPLACED THE PART AT MY COST, WHICH FIXED THE ISSUES. - YES, THE DEALERSHIP INSPECTED AND CONFIRMED THE ISSUE WAS THE CORRODED AND BROKEN GROUND STRAP. - YES, THERE WERE MANY WARNING MESSAGES THAT STARTED TO APPEAR ABOUT 3-4 DAYS PRIOR TO THE COMPLETE FAILURE OF THE ELECTRICAL SYSTEM. I STARTED SEEING A MESSAGE ABOUT SERVICING THE TRAILER BRAKE SYSTEM, AND ANOTHER ABOUT SERVICING THE SIDE DETECTION SYSTEM. THEN A SERVICE POWER STEERING WARNING AND TO DRIVE WITH CARE. THE CHECK ENGINE LIGHT WAS OFF AND ON OVER THAT TIME. - I CHECKED THE WIRE CONNECTIONS IUNDER MY VEHICLE TO CHECK FOR BROKEN WIRES OR CORROSION. I DID NOT FIND ANY. I THEN CHECKED IF A HARD BATTERY RESET WOULD WORK, BUT IT DID NOT. LASTLY, I BOUGHT A NEW BATTERY TO REPLACE THE EXISTING ONE, EVEN THOUGH THE EXISTING BATTERY HAD NO ISSUES EVEN WHEN TESTED UNDER LOAD. THAT RESOLVED THE ISSUE FOR ABOUT 35 MINUTES THAT NIGHT AND THEN THE NEXT MORNING. AFTER THAT, THE ELECTRICAL SYSTEM FAILED AND THE TRUCK WOULD NOT START. AT THAT POINT I GOT TOWED IN TO THE GMC DEALERSHIP. I HAD TO LEAVE THE TRUCK FOR A WEEKEND, AND THE DEALERSHIP DID NOT COME UP WITH A LOANER, EVEN THOUGH I REQUESTED ONE. I GOT THE TRUCK BACK ON MONDAY AFTERNOON AND EVERYTHING WAS WORKING FINE SINCE THEN. - OVER THAT WEEKEND, I WAS AMAZED TO FIND OUT ABOUT THE BULLETIN GM RELEASED TO COVER ONLY SOME TRUCKS FOR THE ISSUE, BUT NOT OTHERS! MY TRUCK IS STILL NOT COVERED, DESPITE THE OBVIOUS SAFETY ISSUES I EXPERIENCED!!
Electrical system, Jun 2, 2026, fire
Fire started under passenger side front seat dashboard when rear defrost was turned on.
Electrical system, May 23, 2026
2020 GMC sierra 1500 infotainment system including navigation,OnStar and voice command, stoped working on Friday May 15th with no prior warning. These systems are integral for modern safe travel and severely affects the value and driver confidence in the vehicle. It seems to be running mechanically sound but, with some of the communications and information systems not working properly I am unsure how much of the info is incorrect like the clock (which can not be set manually). I have scheduled an appointment with the dealer for June 2nd the earliest date available.
Electrical system, Apr 6, 2026
Infotainment screen is flashing different colors and doesn’t work anymore.
Power train, Electrical system, Mar 20, 2026
Truck broke down with a rear-wheel lockup and had the transmission replaced in June 2025. In December 2025 and February 2026, truck lost power two times and entered limp mode while on a major highway and major interstate. The problem was misdiagnosed in June 2025, diagnosed properly in December 2025, but not properly repaired, and diagnosed properly in February 2026. All three times the vehicle had this issue, two of the same exact DTCs were present. This is a safety defect, and I have lost all confidence that the vehicle is reliable enough and safe enough for myself and my family.
Electrical system, Mar 16, 2026
Odometer Fraud. The contact attempted to purchase a 2020 GMC Sierra 1500. The contact discovered a mileage discrepancy. The vehicle was a private sale. At the time of purchase, the mileage was 75,000. At the time of registration, the Carfax Report indicated that the mileage was 175,000.
Electrical system, Engine, Mar 13, 2026
I was driving the truck on the freeway and the engine completely shut off with no warning. I pulled to the side of the shoulder and I could smell a burning smell. The truck wouldn’t start back up or move in neutral. Towed it to a shop and they said it had a camshaft issue and a slight knocking noise when they got it to fire up only would run for a little then shut back off. Now I’m having to replace the whole engine due to being bad with the cam code and knocking.
Electrical system, Mar 12, 2026
The backup camera is too bright at night and therefore useless . Tried searching the web but found no fix that would actually work. Took my truck to the dealer and they never heard of this issue even though there are numerous articles about it on the world wide Web.
Electrical system, Other or unspecified, Visibility/wiper, Jan 23, 2026
Back window leaks down onto electrical compents and causes mold behind rear seat, plus staining mold on headliner
Electrical system, Visibility/wiper, Dec 13, 2025
The morning of December 12th, 2025 I used my vehicle to transport my daughter approximately 5 miles round trip from our home to drop her off at daycare and then I returned home. I used my front and rear defrost elements to expedite removal of heavy condensation which had formed on all windows overnight. This was approximately 7 AM. I parked my truck in the driveway and went inside until approximately 11:45 AM when I went to leave in my truck and noticed the rear sliding window had shattered. The window shattered and distributed tempered glass fragments all over the inside of the cab. Only approximately 10% of the window remained intact. I then reviewed the security camera footage from my driveway and discovered that the window failed entirely on its own with nothing hitting/striking/touching the window, nor any humans or animals in the vicinity. I attempted to take the vehicle to a GMC service department this morning (Dec 13) but due to their demand to keep the vehicle for 2-3 days to investigate yet unable to provide a loaner vehicle, I was unable to leave the vehicle in their possession and returned home. I plan to continue to contact GMC dealership service departments in hope I can find one which can provide a loaner vehicle, as I will need transportation to and from work in the coming days. I do have video footage of the incident although I am unable to add it below.
Electrical system, Engine, Dec 8, 2025, fire
The contact owned a 2020 GMC Sierra 1500. The contact stated that after the vehicle was purchased and while driving at an undisclosed speed, the check engine warning light illuminated. The dealer was contacted. However, the check engine light turned off, and the dealer refused to inspect the vehicle. The contact stated that while driving at an undisclosed speed, the vehicle jerked and the check engine light illuminated. The dealer was contacted. However, the warranty had expired, and the dealer refused to inspect the vehicle. The manufacturer was contacted, and the contact was offered a five-hundred-dollar coupon. The vehicle was taken back to the dealer. However, no cause for the failure was found. The contact stated that an unknown part was replaced. The contact stated that the failure persisted. The contact stated that while turning on the engine, the contact's sister informed him that smoke was emitting from under the hood. The contact turned off the engine, opened the hood, and noticed that all of the wires were melted. The contact splashed water on the wires. The contact checked underneath the vehicle and noticed that the plastic that was burnt was leaking residue. The vehicle was left at the residence where the contact's mother lives. The next day, the contact noticed that the front windshield had shattered due to the heat from the burnt wires. The insurance company was notified and referred the caller to take the vehicle to be inspected. The vehicle was towed to a collision center. The contact was informed that the vehicle had a factory defect. The vehicle was not repaired. The manufacturer was notified of the failure. However, no assistance was provided since the warranty had expired. The failure mileage was approximately 32,000.
Electrical system, Other or unspecified, Fuel/propulsion system, Nov 10, 2025
1. The vehicle’s emissions system is malfunctioning, specifically the ECM (Engine Control Module) related to the exhaust emissions system. The diagnostic trouble code is P2C7A, indicating the system is not performing as expected. Key components such as the NOx catalytic converters and diesel particulate filter have been repeatedly replaced, but the issue persists. The vehicle and all replaced components are available for inspection upon request. 2. The malfunctioning emissions system has led to an exhaust leak that allowed exhaust gases to enter the vehicle’s cab. This creates a hazardous environment for both the driver and passengers, exposing them to harmful exhaust fumes. In addition to reduced engine performance, poorer fuel economy, and emissions non-compliance, this exhaust leak poses a serious safety risk by compromising the air quality inside the vehicle. Prolonged operation under these conditions could lead to adverse health effects and further mechanical failures that impact vehicle safety. 3. Yes. The dealership has diagnosed the problem multiple times. The emissions components have been replaced under warranty on two separate occasions. The dealer attributed the fault to fuel quality; however, Fuel distributor debunked these claims. 4. The vehicle has been inspected extensively by the dealership with invoiced repair work replacing key emissions control components. 5. The check engine light and Service Engine Soon (SES) light have been illuminated with the diagnostic code P2C7A since the initial identification of the problem which started 3JUN24
Power train, Electrical system, Fuel/propulsion system, Nov 5, 2025
Coolant control valve and engine cooling fan
Steering, Electrical system, Service brakes, Aug 25, 2025
Was driving down the freeway around 65 miles an hour attempted to pass a truck when the steering started wobbling the ABS that EMS and the breaking system came on with the check engine light almost had no control and barely avoided having an accident the only way it went back to normal was slowing down.
Engine, Electrical system, Equipment, Aug 4, 2025
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving with cruise control mode set at 55 MPH, the vehicle independently accelerated to 98 MPH, and then the vehicle lost motive power. Additionally, the contact stated that the vehicle had failed to turn off upon pressing the Engine Start/Stop button. No warning light was illuminated. The vehicle was able to restart and was taken to a local dealer to be diagnosed, but the cause of the failure could not be determined. Additionally, the contact noticed that water was leaking inside the vehicle through the rear window on rainy days. The contact stated that the infotainment screen had failed to turn on as intended on some occasions, and the screen had displayed a rearview camera image while the vehicle was in drive(D) on other occasions. The contact stated that while driving at various speeds, the transmission made an abnormal sound, and the RPMs failed to decrease as intended, but suddenly dropped while decelerating. Additionally, the contact stated that the headlights, the fuel pump, and the main pulley were replaced at the local dealer. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 250.
Electrical system, Engine, Jun 30, 2025
Woke up one morning and the entire back seat, entire truck flooring was soaking wet. Got it to Gerber collision in El Reno, Oklahoma. They said that the back window had a crack in it. My insurance said it is a mechanical issue on the sliding back glass and they do not cover such issue. Also want to turn in that the transmission in this truck had to be replaced two week prior to this incident. The truck only had 118,000 miles on it. Safe to say that this 10 point GMC diesel truck is a nightmare and the entire truck is a hazard. They need to take these truck off the market.
Electrical system, Jun 25, 2025
Power Steering works sometimes and then stops Trailer Break system issues
Electrical system, Engine, Jun 24, 2025
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving on a main road at 40 MPH, the vehicle lost automotive power, causing the vehicle to shut off. There was no warning light illuminated. The vehicle was towed to a local dealer where the vehicle was diagnosed, and the contact was informed that the engine wiring harness was faulty and needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 80,000.
Steering, Electrical system, Engine, Jun 3, 2025
Loss of power steering. Loss of engine propulsion at high rates of speed. Engine would not start.
Power train, Electrical system, Engine, Jun 3, 2025
Hi I have always taken good care of my 2020 gmc Sierra 1500 at4 6.2 Kept up with its regular and recommended maintenance. I had no warning signs on the dash. So it surprised me that while on my way to work early one morning I was getting off the highway exit and the truck lost power, my steering wheel hardened and it posed a great threat to my life and others on the road, as it suddenly decelerated in a area where people are driving at accelerated speeds. The whole truck was loosing power and shaking hard as I attempted to steer it to a safe location on the side of the road. Had a mechanic inspect it and they determined The truck ended up with a seized engine. I have since not been able to use my truck for 8 months and still currently paying monthly payments of 1000 to pay it off.
Suspension, Electrical system, Wheels, Jun 2, 2025
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving 60 MPH, the horn failed to function as intended. There were no warning lights illuminated. The contact stated that on a separate occasion, the right lane sensor stopped working as intended. There were no warning lights illuminated. The contact stated that on a separate occasion, while driving 60 MPH in the rain or on rough asphalt, the rear suspension caused the vehicle to fishtail to the right. The contact turned to the left to control the vehicle. The contact stated that the vehicle returned to normal functionality after the failure. The low transmission fluid warning light was illuminated. The vehicle was taken to an independent mechanic, who diagnosed the vehicle with an electrical systems failure. The independent mechanic informed the contact that there was adequate transmission fluid inside the transmission, and it was unclear why the warning light was illuminated. The contact was informed that weights were added to the wheels to balance each wheel. The vehicle was not yet repaired for the other failures. The contact stated that the transmission was replaced a year prior to the failure, and the horn had failed to function soon after the transmission replacement. The manufacturer was made aware of the failure. The failure mileage was approximately 68,000.
Power train, Electrical system, Engine, May 22, 2025
Engine Light came on, performance rough at various speeds / conditions, and smelled like burning and strong urea smell. GM Maintenance identified a failed DEF injector / replaced