Complaint volume
425 consumer-submitted complaints are matched to this model year. Treat the count as a research signal, then read the actual summaries for repeated symptoms.
Complaint records
2020 GMC Sierra Complaints
425 consumer-submitted complaints on record for the 2020 GMC Sierra, grouped by component category.
425 Total complaints
11 Crash reports
4 Fire reports
6 Injury reports
Complaint data reflects consumer-submitted reports. A complaint is not proof
of a defect, recall, or manufacturer fault. Enriched severity fields come
from official bulk records when the complaint can be matched by ODI number.
Buyer interpretation
How to use these complaints before buying
Complaint records are most useful when they turn into inspection points, seller questions, and comparison checks against nearby model years.
Pattern to inspect
The most common categories are engine, power train, electrical system. Use those categories as a test-drive checklist instead of judging the vehicle from the total count alone.
Severity flags
Enriched records include 11 crash reports, 4 fire reports, 6 injury reports, and 0 fatality reports. These fields come from complaint records and should be read in context.
Mileage clue
Mileage is available on 118 complaints, with an average reported failure mileage of 44,233 miles. Compare that with the mileage on the listing.
Questions to ask the seller
- Have you had any problems related to engine, power train, electrical system?
- Can I see recent maintenance and repair records?
- Has the vehicle ever been towed, involved in a crash, or repaired for the same issue twice?
- Can we also check the recall record for this 2020 GMC Sierra?
Used-car checklist
Use these complaints before the test drive.
Build a buyer checklist to turn these issues into questions and inspection points.
2020 GMC Sierra
Build buyer checklist Compare with other years Sends year, make, and model to pre-fill your checklist.
How severe are the 2020 GMC Sierra complaints?
11 Crash
4 Fire
6 Injury
0 Fatality
28 Towed
4 Medical attention
What are the most common 2020 GMC Sierra complaint categories?
ENGINE 125
POWER TRAIN 36
ELECTRICAL SYSTEM 21
POWER TRAIN,ENGINE 17
SERVICE BRAKES 16
STEERING 14
UNKNOWN OR OTHER 14
ENGINE AND ENGINE COOLING 9
SUSPENSION 9
ELECTRICAL SYSTEM,ENGINE 8
425 total complaints on record
Latest complaints
| Date | Component | Summary | Severity | Mileage |
|---|---|---|---|---|
| Dec 2021 | ENGINE | The contact owns a 2020 GMC Sierra 1500. The contact stated that shortly after refueling while driving under 15 MPH, the check engine and service emissions warning light illuminated. The contact stated that an unknown reset was performed related to TSB: 10173675 (Engine). The vehicle was not yet fully repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 46,000. | Crash: No Fire: No | 46,000 |
| Nov 2021 | SUSPENSION | At 8,000 miles I started hearing a clunking noise in my truck when I hit a small bump or back up out of drive way. Brought in and GMC stated it was normal and no issues at walser buick gmc of Roseville. Brought I back again because it was getting worse and could hear it every time I slowed down and accelerated. Then stated they need to order spacer bushings at walser of Bloomington. Then went back for 3rd time and installed them at Bloomington.After 600miles noise was back and is getting worse again. I called Walser of Bloomington again and said I need to drive it for 1000 miles to break in spacers. So now we have 11,000 miles on truck with same noise again and its going back again because needs to get fixed. GMC is just asking for something to happen. Also when this first happened at 8,482miles I was on 35w and the rear end started wobbling and gave me a small death wobble but I slowed down to control it. That’s when I brought it in and it could of hurt or killed somone. | Crash: No Fire: No | Unknown |
| Nov 2021 | SERVICE BRAKES | Brakes have been squealing since 4000 mile mark. Dealer states it’s normal. | Crash: No Fire: No | Unknown |
| Oct 2021 | TIRES | The contact owns a 2020 GMC Sierra 1500 equipped with Goodyear Tires, Tire line: Wrangler AT/S, Tire Size: LT275/65/R20, DOT Number: PJOTJB1V. The contact stated while driving 65 MPH, there was a slight wobble and then an impact was felt when the rear passenger’s side tire tread separated and damaged the rear fender and bumper. The contact pulled over and had assistance replacing the rear passenger’s side tire with the spare tire. The dealer was made aware of the failure and was in possession of the failed tire. The manufacturer was not made aware of the failure. The failure mileage was unknown. | Crash: No Fire: No | Unknown |
| Sep 2021 | ELECTRICAL SYSTEM,SERVICE BRAKES,FORWARD COLLISION AVOIDANCE | Own a 2020 GMC Sierra AT4 with 13K miles and I owned the truck for 1 year. All of a sudden my vehicle started receiving multiple warning messages. Electronic Stability Control, Antilock Braking System, ECM, reduced Engine Power, etc. I see there was a recall for 2019 GMC Sierra's for the same issues. Why isn't 2020 GMC Sierra's not also part of that recall ? It is ridiculous that a brand new truck has these types of serious issues affecting so many vehicles. Why is GMC allowed to continue to sell later model trucks after the 2019 recall with the exact same ESC and Anti-lock Braking system problems ? | Crash: No Fire: No | Unknown |
| Sep 2021 | ELECTRICAL SYSTEM,SERVICE BRAKES,ENGINE | Two times while on the freeway the service parking brake and engine lights came on and starting braking. Could not drive over 20 mile an hour. Both times taking to dealer the lights where not on and they could not find anything wrong. I even have video of it happening. | Crash: No Fire: No | Unknown |
| Sep 2021 | SUSPENSION | The leaf springs appear to have failed. The vehicle is available for inspection. If the leaf spring brakes, control of the vehicle could quickly become an issue. On 9/24/21 I brought my truck into the local GMC dealer for inspection. The service technician indicated the leaf springs show “possible overloading” and recommended air bags to level the truck. The heaviest load for this truck has been a 4,000 lb. fiberglass fishing boat. At this time, no one else has inspected the truck. The truck, when empty, sits lower in the rear than in the front. If a small trailer is attached, it becomes even worse. Oncoming cars flash their headlights thinking mine are on high beam, which they are not. | Crash: No Fire: No | Unknown |
| Sep 2021 | SUSPENSION,POWER TRAIN,SERVICE BRAKES | I purchased the 2020 Sierra 1500 because the label on the truck frame states that it can tow 9300lbs. Subsequently, in April 2021, I purchased a 34' Travel Trailer with a max capacity of 8995lbs. In August, I received a notice from GMC that they overstated the towing capacity by 500lbs. The new towing capacity is 8800lbs. GMC's response to my request for a refund was that they were not going to help me. Their solution is that I can be provided a new sticker by the dealer upon request. This does not resolve my issue, nor the issue of other Sierra owners who purchased this vehicle because of its stated towing capacity. In doing research, it appears that in model year 2014, GMC faced a class action lawsuit for misrepresenting their capabilities. I believe that this malpractice is a safety concern for me and many others. Attached is the towing label on the frame and the letter from GM. | Crash: No Fire: No | Unknown |
| Sep 2021 | ELECTRICAL SYSTEM | Bought 9-4-2020. On 9-4-2021 went start vehicle and no electrical power, battery dead. Will not hold charge to start. Brand new purchased at Morgan GMC in Shreveport Louisiana | Crash: No Fire: No | Unknown |
| Sep 2021 | SUSPENSION | I was driving my 2020 GMC Sierra AT4 at about 15mph on a 2 way city street slowing for a traffic light when my vehicle started to shake violently...at first thinking it was a flat, but the shaking was much different. As I was slowing in anticipation of the light, now at about 5mph, my truck suddenly dropped and stopped. This would have been catastrophic at freeway speeds! I immediately thought maybe someone had tried to steal the wheel overnight as I knew now it was not simply a flat, but knew I had wheels locks and thought that unlikely....this was while I was exiting my now parked truck. I knew the problem was on the front passenger side, and was shocked as I rounded the vehicle from the front only to find the entire front wheel assembly folded flat under my truck. The entire brake assembly was still intact, but the front drive shaft was pulled out, as well as the upper and lower ball joints. The brake hose became severed in this incident. | Crash: No Fire: No | Unknown |
| Aug 2021 | ELECTRICAL SYSTEM,VEHICLE SPEED CONTROL,FORWARD COLLISION AVOIDANCE | Issue 1: Front left sensor(s), after a rain, car wash and now after an oil change, continuously vibrates the drivers seat and the red light warning stays lite indicating that an obstacle is located near the left front of the truck. This has happened on several occasions and after a time both indicator stop. Issue 2: When traveling on a freeway, twice now, the cruise control suddenly disengaged or decreased mileage, as if it had detected a vehicle in front of us. There was no vehicle within a quarter mile of us front or back, nor any vehicles on the side. No debris in the road either. Usually when the adaptive cruise is set and detects something in front the icons on the dash turn orange and starts to flash. That didn't happen, rather the cruise icon changed to blue in color and the truck slowed. This I would consider a safety risk. Both instances (December 2020 and April 2021) have been reported to a dealership and noted in a file. When the customer care person attempted to get malfunction codes, nothing appeared to be wrong with the vehicle. | Crash: No Fire: No | Unknown |
| Aug 2021 | ENGINE | Repeated issues with exhaust and emissions components. | Crash: No Fire: No | Unknown |
| Aug 2021 | ENGINE | Found improperly installed rear seals. The truck leaked oil and had to be towed to gmc dealership in Monahans Texas to be repaired. 1 month later the truck leaked oil again. | Crash: No Fire: No | Unknown |
| Jul 2021 | ENGINE | Rear main oil seal failure causing truck to lose all oil, leaking all over truck, trail leading to drive and garage; possibility of engine seizing up while driving causing an accident, confirmed by dealer, covered by warrenty, is a known issue, no warning lights, messages, or other symptoms of problem, NHSTA has issued a bulletin for this problem | Crash: No Fire: No | Unknown |
| Jun 2021 | ELECTRICAL SYSTEM | Service ESC, Service Power Steering, antilock brakes disabled all flashed on information center of vehicle. Service engine light, antilock brake light, ESC, low battery all illuminated. Vehicle would not start - try to start it would go through all issues on information center. This is the same ESC issue described for 2019 Silverado and GMC Sierras. | Crash: No Fire: No | Unknown |
| May 2021 | ELECTRICAL SYSTEM | The display for the backup camera and infotainment system became blank. Other owners have the same complaint. This is a serious safety issue because I was backing up when it went blank. | Crash: No Fire: No | Unknown |
| May 2021 | SUSPENSION,SERVICE BRAKES,ENGINE | On Saturday, May 22, 2021, My wife was returning from fairgrounds in Waxahachie, TX. She remote-started the car, and the vehicle started. As it started to rain and was getting muddy, and the grounds are in a grass field (No large rocks, hills or debris to climb as it's cleared land), she shifted the vehicle into 4wd high incase the field was slick. She started to drive and received several warning lights, "Service ESC, Service traction control, brake light warning and check engine light". The vehicle also had a noticeable wobble to the wheel and felt off balance, jerky, and had speed limited. My wife turned the vehicle off and back on and some of the lights went off, and the vehicle did not lurch or wobble anymore. The vehicle had a tire changed at the dealer the day prior, so I am unsure if that tire change is related or not. Now the vehicle shows an alert "check engine, service emissions system". I am having the vehicle towed to the dealership tomorrow for diagnostics. All lights except the check engine light have since turned off since powering off the vehicle. | Crash: No Fire: No | Unknown |
| May 2021 | AIR BAGS | Airbags failed to deploy after striking a street light pole head-on. The impact hit just right of dead center of the grille and shoved the front end back approximately 2 feet into the engine. There were no dash lights or warning lamps illuminated before the collision. I have notified GM and received a case number. I also have filed an insurance claim and the vehicle has been inspected by a reputable body shop and has been deemed a total loss. A police report was also filed. The vehicle is scheduled to be picked up by the insurance company on 5/18/21. | Crash: Yes Fire: No Towed | Unknown |
| May 2021 | STEERING,ELECTRICAL SYSTEM,UNKNOWN OR OTHER | IT WAS FINE AND WE DROVE TO OUR NEIGHBOR, PARKED ABOUT 15 MINS. WHEN WE STARTED THE TRUCK TO TURN BACK, THE STEERING WAS SUPER HEAVY, WITH 2 MESSAGES POP UP ON THE DASHBOARD: SERVICES ESC, AND SERVICE POWER STEERING DRIVE WITH CARE. TRIED SEVERAL TIMES TO RE-START THE TRUCK, IT'S KEEP THE SAME. IN OUR NEIBORHOOD, PARROT TULIP VIEW, PFLUGERVILLE, TX 78660. RAINING ALL NIGHT, NOT SURE IF IT'S RELATED TO THE WEATHER. | Crash: No Fire: No | 10,300 |
| Apr 2021 | POWER TRAIN | TL* THE CONTACT OWNS A 2020 GMC SIERRA 1500. THE CONTACT STATED THAT UPON EXITING THE VEHICLE, HE NOTICED THAT THE VEHICLE WAS LEAKING AN UNKNOWN FLUID. THERE WAS NO WARNING LIGHT ILLUMINATED. THE VEHICLE WAS TAKEN TO SIMPSON BUICK GMC OF BUENA PARK (6600 AUTO CENTER DR, BUENA PARK, CA 90621) WHERE IT WAS DIAGNOSED WITH THE TORQUE CONVERTER NEEDING TO BE REPLACED. THE VEHICLE WAS REPAIRED HOWEVER, THE FAILURE RECURRED. THE MANUFACTURER WAS NOT INFORMED OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 11,000. THE VIN WAS UNAVAILABLE. | Crash: No Fire: No | 11,000 |
| Apr 2021 | VEHICLE SPEED CONTROL | THE VEHICLE HAS MADE "PANIC STOPS" AT HIGHWAY SPEEDS 5 TIMES WHEN USING ADAPTIVE CRUISE CONTROL WITH NO INPUT FROM DRIVER OR SURROUNDING ENVIRONMENT I.E.. CLEAR ROAD, NO TRAFFIC, SUN OR NO SUN. | Crash: No Fire: No | 16,000 |
| Mar 2021 | STEERING,SERVICE BRAKES | MY TRUCK TUESDAY MARCH 16TH HAD ME UPDATE SOFTWARE AS SOON AS I GOT TO WORK, AFTER IT WAS DONE I GOT OUT OF MY TRUCK AND IT WOULD NOT LOCK WITH PUSH BUTTON OR FOB. WHEN I GOT INTO MY TRUCK TO GO HOME 10HRS LATER IT MADE A BUNCH OF CLICKING NOISES AND AFTER A MINUTE IT SHOWED UPDATE COMPLETE ON SCREEN THEN STARTED. THE VERY NEXT DAY I DROVE BACK TO WORK WHICH IS 22 MILES. WHEN I TOOK MY TRUCK TO LUNCH THREE BLOCKS AWAY I HAD ESC SERVICE LIGHT AND SERVICE PARKING BRAKE ACCOMPANIED BY CHECK ENGINE LIGHT. I CALLED LOCAL DEALERSHIP TO GET IT LOOKED AT AND THEY SAID FRIDAY WAS AS EARLY AS I COULD GET IT IN. I LEFT WORK EARLY AT 1:30 AND TRIED TO DRIVE IT AND IT WAS SQUALENE LIKE A BAD POWER STEERING PUMP AND SHAKING AS I DROVE. I WENT AHEAD AND TOOK IT THE DEALER. | Crash: No Fire: No | 20,500 |
| Mar 2021 | SERVICE BRAKES,FORWARD COLLISION AVOIDANCE | 2020 GMC SIERRA SLT VIN:[XXX] 15,700 MILES. BRAKING SYSTEM FAILURE AT ABOUT 45MPH ON HIGHWAY 78 IN LOGANVILLE, GA APPROACHING AN INTERSECTION WITH RED LIGHT, VEHICLE SEEMED TO LOOSE ALL POWER BRAKING. I STOOD WITH ALL I COULD ON THE PEDAL, AND TURNED TO AVOID REAR ENDING STOPPED VEHICLES, RUNNING INTO MIDDLE OF THE INTERSECTION BEFORE IT STOPPED; NO ACCIDENT ! DEALER IS REPLACING MASTER CYLINDER AND BOOSTER BRAKING SYSTEM, ALONG WITH COMPUTER SYSTEM UPGRADE. MY CONCERN IS THE DEALERSHIP AND NHTSA IS AWARE OF THIS ISSUE, YET NO CEASE AND DESIST DRIVING DIRECTIVE HAS BEEN ISSUED ! INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). *TR | Crash: No Fire: No | 15,700 |
| Feb 2021 | STEERING,ELECTRICAL SYSTEM,UNKNOWN OR OTHER | WHEN STATIONARY AND PREPARING TO START VEHICLE INTERMITTENTLY SEE "SERVICE STEERING COLUMN LOCK" MESSAGE APPEARS AND DISAPPEAR ONCE VEHICLE IS STARTED. THIS WAS PREVIOUSLY SUPPOSED TO BE ADDRESSED WITH SERVICE BULLETIN 20-NA-21 HOWEVER BEING TOLD BY SERVICE DEPARTMENT THAT VEHICLE HAS ALL CURRENT UPDATES APPLIED A YEAR AGO, INCLUDING THE ONE THAT SHOULD OF ADDRESSED THE ISSUE. TOLD THAT THE VEHICLE HISTORY SHOWS RECORDS OF PAST "LOSS OF COMMUNICATION TO DIC" BUT AS THEY CAN'T IMMEDIATELY REPRODUCE NO ACTION WAS TAKEN. | Crash: No Fire: No | 8,800 |
| Feb 2021 | EXTERIOR LIGHTING,UNKNOWN OR OTHER | DANGEROUS VISIBILITY HAZARD WHEN BACKING UP VEHICLE AT NIGHT. INFOTAINMENT SCREEN SWITCHES TO "FULL BRIGHTNESS" WHEN BACKUP CAMERA IS ACTIVATED, RESULTING IN BLINDING LIGHT TO DRIVER. DRIVER CAN NOT BACKUP SAFELY WITHOUT PHYSICALLY COVERING THE SCREEN TO REGAIN VISIBILITY. SCREEN BRIGHTNESS REFLECTS OFF ALL 4 WINDOWS, WINDSHIELD AND BACK GLASS. SIDE MIRRORS ARE UNUSABLE IN THIS CONDITION. THERE WAS A FIX FOR THIS ISSUE ON PREVIOUS GM MODELS, (PRIOR TO 2018), HOWEVER NO FIX FOR 2019 - PRESENT | Crash: No Fire: No | 20,000 |