7.7

pretty bad
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
5,810 miles

About These NHTSA Complaints:

The NHTSA is the US gov't agency tasked with vehicle safety. Complaints can be spread across multiple & redundant categories, & are not organized by problem. See the Back button — blue bar at the very top of the page — to explore more.

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problem #20

May 152021

Sierra 1500

  • miles
The electric power steering failed while accelerating into a turn from a stop at an intersection. The wheel was jerked from my hands, and the engine stalled, all electrical failed momentarily. Within a couple of seconds everything returned to normal. This has happened several times since I purchased this vehicle. Also the electrical power steering drops out quite often at low speeds, such as in parking lots. No warnings have ever been given. In May of 2021 the dealer replaced the steering rack, the problem has continued intermittently to this date. I have researched for recalls on this problem and found that GMC issued a recall for years 2014-2017, and am amazed that they could just declare the problem fixed, and leave such a dangerous problem unresolved!

- Palmetto Bay, FL, USA

problem #19

Apr 232023

Sierra 1500

  • miles
Loss of dash electrical system and service stabillitrac warning came on when power was restored along with service suspension warning light. Headlights flicker and engine starts powering down before power comes back on by itself. If fuse to suspension is pulled or negative is removed and replaced, all warning lights go away.

- Goshen, IN, USA

problem #18

Apr 112023

Sierra 1500

  • miles
Break system is making scratching noises as if it is a caliber breaking problem or a caliber piston problem, it is also setting off the trailer breaking system light on the dash as well as the trail traction control light.

- Cathedral City, CA, USA

problem #17

Jan 112023

Sierra 1500

  • miles
The main harness under the truck, front to back. There was a separation from the conduit, wires exposed and were arcing. Truck would not start. I have since had it fixed. I just feel truck is not that old, to soon for a problem like this. And it cost a lot of money.

- Macomb , MI, USA

problem #16

Dec 242022

Sierra 1500

  • miles
I purchased my 2018 GMC Sierra 1500 pickup truck new in 2018. To date it only has 28K miles on it. I have never used the trailer breaking system that it came equipped with. On 12/24/22 we were traveling to a family function for Christmas. The "service trailer break system" warning message came on and the chime chimed continuously until I got to my destination, about an hour away. This chime was very distracting and there was no way to turn it off. After arriving at my destination I turned the truck off hoping it was just a fluke. When I started the truck back up the "service trailer break system" warning light and chime continued. It continued for an hour on my way home. Again, this was very distracting and I was unable to focus 100% of my attention on the road and my driving. Thank fully I made it home okay. On 12/27/22 I took the truck to my mechanic to have him take a look. He said he has heard of this issue with these pickups. His diagnostic confirmed that the trailer breaking switch (on the dash) was functioning properly but said that the chassis control module was likely the culprit. He replaced the control module and it had to be programed by a factory technician. After this part was replaced the warning light or chime does not come on anymore. I have the defective part for inspection and the bill totaling $1191.86 for the repair upon request.

- Lake Oswego, OR, USA

problem #15

Sep 122022

Sierra 1500

  • miles
While driving 35 miles per hour in the early morning hours I came to a 4-way intersection and applied the brakes slowly. Suddenly, I lost all power in the brakes and the steering wheel locked up. The lights, and stereo remained on, and my dash board display immediately showed a red check engine light. I immediately turn on my hazard lights, turned the ignition key off and tried to restart the truck. There was no clicking sounds. The truck would not start but the lights dimmed and the dash display now showed an intermittent yellow, flickering check engine light. After roughly 30 minutes while waiting for AAA to arrive I tried the ignition key and the truck started up with a red check engine light. Rather than attempting to drive I had AAA tow my vehicle to the Chevrolet dealership where I purchased the truck.

- Eugene, OR, USA

problem #14

Jan 012022

Sierra 1500

  • miles
The light in the dashboard gose dark and it gives me a warning collision alert and the tiers they spin out of control when turning or when I I-€™m driving I think it-€™s the tiers they have a lot of tread still-€¦

- North Las Vegas, CA, USA

problem #13

Feb 042022

Sierra 1500

  • miles
I was stopped at a fast food drive thru and then I tried to go to the next window and the truck wouldn-€™t move at all it will just rev so I put it in parked turned off the truck and turn it back on put it on drive and was able to move for like 40 ft then it did it again so I had it towed to my home

- Seagoville , TX, USA

problem #12

May 162022

Sierra 1500

  • miles
Trailer brake modulator on 2018 GMC Sierra does not consistently signal trail brakes to work when needed on our 7,500 pound RV trailer. GMC dealer eventually found that the battery cables were undersized as installed with the factory towing package on the 2018 GMC Sierra. The undersized battery cables do not consistently deliver adequate voltage to the trailer brake modulator on the GMC Sierra, so inconsistent electric brake function for our 7,500 pound RV trailer. Dealer had difficulty diagnosing the problem as being the wrong factory-installed battery cables to go with the factory-installed trailer towing package. So it cost us $1,600 to have the GMC dealer correct a problem caused by the GMC factory installing undersized battery cables. Fortunately, this did not result in a collision for us, but it might for someone else. Our 2018 GMC Sierra kept sending vague, randomly timed warnings to the dashboard to "Check Trailer Wiring." Very frightening, dangerous and costly (for us) mistake by GMC. Will the brakes work this time, or fail on the way home? Problem started in 2021 RV season, but took awhile for us to recognize the need to take to the GMC dealer for them to diagnose base cause. Took time for us to experiment changing trailer wiring connector on bumper and trailer brake control on the dash. Work for awhile, then fail. Work for awhile, then fail. Arrrrgh! Ask GMC to put more adequate battery cables on ALL their vehicles, please.

- Merrifield, MN, USA

problem #11

Jun 012022

Sierra 1500

  • miles
SERVICE TRAILER BRAKE SYSTEM - warning

- Kansas City, MO, USA

problem #10

Mar 192022

Sierra 1500

  • miles
-€œService- trailer brake system-€ light keeps coming on. It is super repetitive. It comes on about every 30 seconds. It-€™s a loud beep that lasts quite a few seconds. Eventually, the beeping did not stop until the truck was stopped. Truck was just bought yesterday. Happens at any speed, even when stopped.

- Old Hickory, TN, USA

problem #9

Jan 112022

Sierra 1500

  • miles
Im getting a service trailer brake system soon message on dash.

- Brooksville, FL, USA

problem #8

Dec 012021

Sierra 1500

  • 77,000 miles
The contact owns a 2018 GMC Sierra 1500. The contact stated while driving approximately 70 MPH, the trailer wiring harness system warning message was illuminated. The vehicle was taken to a local dealer where it was diagnosed with needing the wiring harness replaced; however, the vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 77,000.

- Boise, ID, USA

problem #7

Nov 172020

Sierra 1500

  • miles
At 50,000 miles the "service trailer brake system" error message appears constantly due to factory defects and its very common. These trucks should be recalled everyone is in danger on the roads and its a very common problem. I have not taken it to the dealer because i should not have to pay for this very common problem, it should be recalled.

- Carolina Beach, NC, USA

problem #6

Nov 112021

Sierra 1500

  • miles
The truck displayed warning lights for ABS, traction control, trailer brakes, and front park assist. Additionally speed control (cruise) did not function. This presented a safety issue. I took to dealer asap. They repaired by replacing left rear wheel speed sensor. Cost about $216. Appears to work correctly at this time.

- Mt. Vernon, IL, USA

problem #5

Oct 012021

Sierra 1500

  • miles
Battery dies after 5days of not being driven. Battery continues to go dead, dealer states nothing is wrong. No repairs were made. Stranded 5 times with a dead battery

- Lapeer, MI, USA

problem #4

May 022021

Sierra 1500

  • miles
Check engine came on and says manufacture specific issues/codes. Safety restrain system. P10e4

- Midlothian, TX, USA

problem #3

Nov 202019

Sierra 1500

  • 27,000 miles
The first thing that happened was that all of the electrical systems on my truck went out and my truck would not start. It finally started but it would not move finally it would move but very slowly this happened on 11/20/2019 I have documentation through onstar for this incident. My brakes started slipping on 07/01/2020 and still do not work properly. My transmission has never shifted correctly. When I accelerate or when I slow down there is a shudder and a jerking sound. After sitting for a while when my truck is put in reverse it hesitates and then seems to jump into gear.

- Owens Cross Roads, AL, USA

problem #2

Jan 042020

Sierra 1500

  • 12,000 miles
My truck locked itself with the engine running when I was parked in the driveway. Also have had the back driver side window roll itself down part ways without me initiating it. Another occasion I put the truck in gear to drive position and the brake or something had it locked preventing me from moving either direction ie; drive or reverse. Was then parked in home garage and attempting to back out.

- Mooringsport, LA, USA

problem #1

Dec 022017

Sierra 1500

  • 200 miles
My vehicle is hacked anytime I am driving the vehicle I am not in full control. The vehicle steers itself left or right while driving, the brakes are always on while driving sometimes braking harder but always on. The infotainment system has many glitches. This vehicle has been back to the dealership more than 15 times has been out of service over 35 days GM even flew a engineer/tech to inspect the vehicle and says they couldnt find anything. Therefore this vehicle is hacked there are so many issues and glitches and the fact that the truck only acts like this when I am driving no one else. Like it can be turned on and off instantly. I have tons of videos pictures and supporting documents backing this. I need help this is a serious issue and there is so much more to it than I can type here someone please get ahold of me to help or point me in the right direction. This vehicle will be returned to GM soon as they are doing a vehicle replacment per all the issues but this needs further attention because if this can happen to me it can happen to anyone. Please help

- Pasco, WA, USA