10.0

really awful
Crashes / Fires:
3 / 1
Injuries / Deaths:
3 / 0
Average Mileage:
5,447 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2020 GMC Sierra 1500 brakes problems

brakes problem

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2020 GMC Sierra 1500 Owner Comments (Page 1 of 2)

problem #30

Feb 032024

Sierra 1500

  • miles

A D V E R T I S E M E N T S

Lost break, second time this month, showing break failed 40 mph max speed, abs light on, break light on, and 2 more light on the car with antislipiring or something like that, the another one no idea what it

- Sebring, FL, USA

problem #29

Nov 052023

Sierra 1500

  • miles
ABS LIGHT LIMITED TO 43 MPH ESC system Steering assist reduced Service Trailer Brake System Engine light

- Hallsville , TX, USA

problem #28

Aug 242023

Sierra 1500

  • 69,000 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated while driving 60 MPH, the service brake, check engine, and ABS warning lights were illuminated. The contact took the vehicle to an independent mechanic to be diagnosed and it was determined that the passenger-??s side rear caliper needed to be replaced. The vehicle was not repaired. The vehicle was taken to the local dealer to be diagnosed, and the contact was informed that the rear passenger-??s side caliper needed to be replaced. The vehicle was not repaired due to the parts not being available. Upon investigation, the contact associated the failure with NHTSA Campaign Number: 20V116000 (Service Brakes, Hydraulic) however, the VIN was not included. The manufacturer had been informed of the failure. The failure mileage was approximately 69,000.

- Swansea, IL, USA

problem #27

Apr 292023

Sierra 1500

  • miles

A D V E R T I S E M E N T S

We were hauling a trailer and driving approximately 65-70mph with cruise control enabled. The vehicle randomly disengaged cruise and the ABS telltale illuminated, lost brake functionality completely. Safety of my family and other vehicles around us was compromised! Downshifted to try and navigate the vehicle to the side of the road and the ESC warning text came on the screen. Was able to luckily stop vehicle by downshifting. Turned off ignition and then cycled back to run, brakes and all warnings were cleared. Started driving vehicle with flashers on the side of the road see what would happen and approximately ten miles later same thing happened but this time brake functionality was reduced significantly but not completely but still had to downshift to stop. Called GMC and was told this was not a recall even though vehicle brakes randomly stopped working. Told us they would do nothing since the vehicle was out of warranty 80k miles and warranty was 60k and also since no one was hurt. We were 1-2 hours from being in the Mountains driving and not sure we would be here today if this had happened in the Mountains! Dealership ordered a new master brake booster and ABS. When installed the part would not flash and GM engineering told them to replace the part a second time.They we-??re told to keep flashing till it takes even though the second module was also bricked. Seems strange a new part would be broken as well and the master cylinder was resetting. Dealership states the vehicle is fixed but the safety of my family and others driving around me were in extreme danger when this happened. Do not feel safe driving this vehicle and not convinced this will not happen again. When we called GM they told us they are receiving many calls about this happening to AT4 vehicles but they have not issued a recall yet. Submitting this because vehicles should not randomly lose brake functionality and do not want others at risk or my family.

- Alpena, MI, USA

problem #26

Dec 282021

Sierra 1500

  • miles
I own a 2020 GMC Sierra 1500 4-Cyl, Turbo, 2.7 Liter with 20K miles and I owned the truck for almost 2 years. All of a sudden my vehicle started receiving multiple warning messages. While driving I stopped, and when traffic stopped in front of me the engine died all the lights were on warning messages on the dashboard started showing up. Electronic Stability Control, Antilock Braking System, ECM, reduced Engine Power, etc., and the brakes were hard to step on it and the steering wheel hard to turn, I took my foot off the brakes and pressed it again to start. It started but the check engine light was still on, this happened FOUR times already and THREE times while parked when I tried to start, after a few tries giving few minutes intervals, it will start with all the lights on and warning messages on the dashboard start showing up. Electronic Stability Control, Antilock Braking System, ECM, reduced Engine Power, etc., and the brakes were hard to step on it and the steering wheel hard to turn.

- Aventura, FL, USA

problem #25

Jan 162023

Sierra 1500

  • miles
Normal driving conditions vehicle decelerated and warning lights and notification appeared. Warning were -??Service ECS-?? and -??Steering Assist is reduced Drive with care-??. Shut off vehicle for 30 minutes and warnings were no longer present and vehicle drove normally. Happened again 24 hours later. Received email notifications from GMC to arrive within one day. This was a know recall of the previous model year.

- Two Harbors, MN, USA

problem #24

Dec 272022

Sierra 1500

  • miles

A D V E R T I S E M E N T S

i was stopped at a red light and when the light turned green I accelerated and the vehicle shut off and then came back on. when the vehicle came on i had a service esc light and a system break failure warning telling me not to exceed 62mph. i made it back to my house driving with extreme caution. the breaks were very delayed while driving.

- Bakersfield, CA, USA

problem #23

Sep 012022

Sierra 1500 6-cyl Diesel

  • miles
Brake pad monitoring system alert came on driver information center warning screen. Brought to local dealer who told me I needed new brake pads. There is a current safety bulletin on the NHTSA.GOV website for the 2019 model year GMC Sierra, as well as the 2019 Cadillac CT6, but not he 2020 model year. The week prior my driver information center reported front brakes in the high 80's and the rears in the low 90's in terms of percentage of brake life remaining. How can the system go from being safe to being unsafe in a week (and less than 200 miles)? At this point I don't know if my vehicle has a safety problem with my brakes or if there is a sensor and programming issue as described in recall N192264451. I have no observable issues while braking - no pulsing, noise, chattering - that would indicate any brake problems. My only inclination is the alert on the driver information center. Both local dealer and GM customer service are telling me to perform service and pay out of my pocket. This seems inconsistent based on the above recall.

- Saranac Lake, NY, USA

problem #22

Jul 082022

Sierra 1500

  • miles
The truck stated to have the check engine light on, by the time that happened the brakes were hard to step on it and the steering wheel hard to turn, I had been asking to GMC superior of Siloam springs to check the truck because, got scared while I couldn't make stop the truck while on traffic, but they don't had open appointments for that day or the other following days, so a week after they got one and I missed because my work, I set another one at GMC on Springdale but they want me to charge me whenever the truck has an extended warranty, so I told them to leave it like that so finally got another appointment at Siloam springs location but while driving down there the same thing happened all the light on warning messages on the dash board start showing up and the brakes were hard to step on it and the steering wheel hard to turn, I got told them what was happening, about and how exactly happened. That day after 30 minutes I got a call saying that it was fixed I still asked if they were sure he said yes, the next day I almost crashed with a neighbor at my work place because I couldn't stop the truck, so today I took back the truck and the guy at the desk told me that they may just erase the codes and don't really checked what was wrong, I'm just filling this report because even if I got full coverage on that truck, I'm not gonna be responsible if I'm involved in an accident.

- Springdale, AR, USA

problem #21

Aug 092021

Sierra 1500

  • miles
This vehicle was involved in a fatal crash when it rear ended an SUV stopped at a red traffic light. The driver alleges mechanical failure of the brakes. Police performed a vehicle download which captured 5 seconds of pre-accident data. The download shows the accelerator pedal was fixed at exactly 57% the entire 5 seconds pre-crash while the driver simultaneously applies the brakes the entire 5 seconds. A city bus captured the crash on a dash camera. Despite the driver desperately applying the brakes, the vehicle's speed continued to increase and the driver was unable to avoid the collision, and burst into flames upon impact. The vehicle mileage is less than 2,500.

- Phoenix, AZ, USA

problem #20

Nov 172020

Sierra 1500

  • miles

A D V E R T I S E M E N T S

Brakes have been squealing since 4000 mile mark. Dealer states it-??s normal.

- Northridge, CA, USA

problem #19

Sep 242021

Sierra 1500

  • miles
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 "

- Jessup, MD, USA

problem #18

Sep 182021

Sierra 1500

  • miles
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.

- Pasadena, TX, USA

problem #17

Aug 022021

Sierra 1500

  • miles
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.

- Fairport, NY, USA

problem #16

May 222021

Sierra 1500

  • miles
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.

- Fort Worth, TX, USA

problem #15

Mar 162021

Sierra 1500

  • 20,500 miles
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.

- Burbank, OK, USA

problem #14

Mar 092021

Sierra 1500 8-cyl

  • 15,700 miles
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).

- Loganville, GA, USA

problem #13

Dec 302020

Sierra 1500

  • 5,000 miles
Car was idling and parked. Warning code showed up on dashboard ESC, electronic stability control, reduced engine power. Vehicle then displayed transmission disruption, warning light displayed as well. I was able to drive it to the dealership but the performance of the vehicle was limited by the reduced engine power. Transmission was hesitating and clunky during gear changes. My Sierra has 5,000 miles on it and the transmission was already replaced at 2,000 miles. GMC has a serious problem with this make and model. Unsure what the resolution will be, but I am no longer confident in the product GMC is selling.

- Toms River, NJ, USA

problem #12

Dec 202020

Sierra 1500

  • 15,000 miles
On two separate occasions, the truck has been dead when attempting to crank. There were no lights or devices left on after the previous time the truck had been used. Something is drawing power from the battery causing it to be dead. After recharging the battery, the check engine codes read that there is a problem with 'brake light illumination.' Help in determining wha T is causing the battery to die on such a new vehicle would greatly appreciated! I'm uncertain at this time as to whether or not the brake light illumination is causing a safety hazard.

- Greenwell Springs, LA, USA

problem #11

Dec 102020

Sierra 1500

  • 6,400 miles
After having all sorts of warnings over time like "service ESC, " "service parking brake, " and more, I now see "brake system failure: 62 mph top speed" flash across my dash. I am reading and hearing that this is a very dangerous problem. New truck. Brand new. Had it less than a year. Brake message always on start up.

- Sierra Madre, CA, USA

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