2021 GMC Sierra 1500 Problems and Top Complaints – Is Your Car A Lemon?

Air bags, electrical system, engine, and structure issues among the top complaints received by the NHTSA from vehicle owners

Updated on Author: Brian Jones

Among full-size trucks, the 2021 GMC Sierra 1500 stands out as a more luxury-minded model. However, the automaker claims it still offers “capability at its boldest.” Yet, customers have been spending all of their time complaining about the air bags, engine, electrical system and structural defects.

Click on other model year to view more problems: 2019   2022   2023

Problems with the Air Bags

One of the most important safety features of any vehicle is the air bags. Without properly working air bags, occupants can become severely injured during an impact. That’s what is shown with the 2021 GMC Sierra 1500 trucks.

One NHTSA complaint states, “Airbag light and ‘Service Safety Restraint System’ keep flashing on and off intermittently. Sometimes every 5 seconds. Sometimes once or twice a day. This is a known issue with 2021 GM trucks and SUVs. Trying to get vehicle in for service but dealer said they are booked 2 weeks out and won’t give loaner vehicles at all anymore. The vehicle has less than 2000 miles on it.”

It turns out that the NHTSA is currently performing an investigation into the air bag defects (Action Number PE21010). With so many complaints present, the Office of Defects Investigation (ODI) is looking into what’s happening with select GM vehicles. In many cases, the air bags aren’t even deploying during an accident. Apparently, GM doesn’t believe that air bags are an essential component of “capability.”

2021 GMC Sierra 1500 Complaint Summary

Complaint Category Number of Complaints
Electrical System
Service Brakes
Power Train
Fuel/propulsion System
Unknown Or Other
Air Bags
Lane Departure: Assist
Seat Belts

Electrical System Problems

When it comes to having a faulty electrical system, sometimes the issues go beyond not being able to get a favorite device connected. In the case of the 2021 GMC Sierra trucks, it could actually mean a fire.

Read this Edmunds review. “Bought a 2021 GMC Sierra sky. All the bells and whistles. Had it 5 months with 3400 miles.  Came back from store and parked it in driveway. Went in the house and my wife said your truck is smoking. Ran out and flames under hood. Five minutes later entire front end of truck engulfed in flames. Total loss. I was just lucky I was out of it. No indication of problems while driving.”

Aside from car fires, GM has been known for creating faulty electrical systems. In fact, the 2019 and 2020 models faced class-action lawsuits because of the defective seven-inch infotainment systems that the company continued to install in vehicles after the malfunctions were revealed. If a company is willing to use faulty equipment on purpose, it can’t be trusted to manufacture a truck with any integrity. Such is the case with the pickups that are spontaneously combusting.

Don’t be stuck with a lemon. You have legal rights to cash, return or buyback.

The law makes GMC pay legal fees.

We've fixed thousands of lemon problems. Message or call 877-795-3666 today.

Problems with the Engine

It has become clear that GM doesn’t put much time into manufacturing a decent pickup. Even more problems can be seen with the engine design.

One Edmunds review states, “My 2021 GMC Sierra 1500 had to have new lifters and push rods put in at 3600 miles then again at 5200 miles had the same problem waiting on dealership and General Motors to get back with me. I think they should buy back this truck in my opinion nobody should have this problem with a brand new truck purchased in January 2021.”

Surprisingly, the company isn’t hiding these issues from the general public. Service Bulletin #PIP5776C says that vehicles are suffering from misfires because the lifter is coming apart. To repair the issue, the four lifters and the lifter guide must all be replaced. The question is – does GM continue to put these same faulty lifters in engines as a replacement? History tells us that is probably what is going to happen, which is in itself one of the “boldest” moves this company could do at this point.

Structural Problems

A final look at the GMC Sierra 1500 structure reveals the same level of defects everyone anticipated. It’s clear that this luxury-focused truck is nothing more than a piece of crap.

Another NHTSA complaint reads, “Sun glare reflects off center console cup holder with such intensity it’s hard to focus on the road even with sunglasses on.”

This is just one minor problem of many. For example, NHTSA Campaign Number 20V811000 states that the wrong bolts were used to attach some of the seat belts. Without these bolts in place, the seat belts fail to restrain occupants during a collision. Additionally, NHTSA Campaign Number 20V684000 says that some tires were overcured, which can lead to a break in the sidewall creating sudden air loss and a blowout. From tires that blow out to seat belts that don’t work and air bags that won’t deploy, occupants are merely asking for trouble every time they get into this truck. However, the structural issues aren’t just related to the safety of the vehicle, but also its appearance. Service Bulletin #19NA255 talks about metal corrosion and rusting along with the frame peeling on these newer trucks. Hey, at least the appearance matches the insides – it’s defective whichever way you look at it.

Your Lemon Law Legal Rights

Think you have a lemon? Sit back and let the experts work out your lemon case at no cost to you. The law makes GMC pay legal fees. You may be able to get your lemon out of your life. Every year, auto manufacturers buy back, replace or pay cash settlements to thousands of ‘lemon’ owners like you.

About the Author:

Brian Jones spent more than 30 years working as an ASE Certified Master Tech and Parts Specialist at multiple dealerships. Brian has become an authority in the industry, traveling across the country to consult for car dealerships and contributing his expertise as a writer for several major automotive publications. In his spare time, Brian enjoys working on pickup trucks, muscle cars, Jeeps and anything related to motorsports.

See more posts from Brian Jones
  • Paul G

    I have a 2021 GMC Sierra AT4. The truck has been maintained and is mostly used in fair weather conditions. I live in south Louisiana and it has been raining off and on the past couple days. Leaving my g/f house I decided to engage the trucks 4 wheel drive for extra control on the wet roads. I followed the owners manual instructions and engaged the transmission. I put the truck in reverse and it started bucking and the steering was tight. I put the truck in drive and it made a loud noise and continued to buck. I stopped on the road, put the truck in park and set the settings back to two wheel drive. I left with no problems until that night. It’s foggy, still raining and I’m driving well below the posted speed limit when my check engine light comes on. Then the whole brake system warning lights light up as I’m approaching a red signal light. I pressed the brakes only to learn I had none. No vehicles were in front of me and I went through the light. Eventually, after applying the brakes several times they started working again, but the check engine light was still on. I brought the truck to the dealership where it was purchased and wrote my complaint on their sign in sheet. Every complaint I recorded the technician questioned me trying to find faults in my operation of the truck. I left it with them to fix the problem and haven’t heard anything back from them yet. As I’m typing this message I’m getting more upset because I’m realizing I could have gotten killed or killed somebody because the brake system on my 2021 truck with 32,000 miles brake system failed. I can’t help from thinking about the fact the truck is an All Terrain vehicle. With that in mind does this mean I’m stuck with a truck that I can’t use for the pleasure it was built for? An All Terrain AT4 GMC that can’t get wet? What should I do?

  • Sandra L

    I purchased a 2021 GMC Sierra 4×4 new prior to the vehicle warranty expiration the lifters needed replacing. I have been experiencing either brakes or some rear or transmission problem.
    Recently the check engines light came on. Code 1467 emission problem. Paid to have repairs done. Learned that the 2020 and 2019 had same problem causing a recall. Called GMC getting no where. All of these problems GMC should have to buy this junk back. A supervisor (retired) said Mondays and Fridays the workers were either intoxicated or hung over.

  • Lonnie G

    NEWS FLASH GMC Freedom Buick GMC. First advise do not buy GM products. I have a been GM customer for at least 45 years and in the last twenty years most of them have been not a reliable low maintenance vehicles. I have purchased the following new, 2000 Chevrolet C1500 had a loud engine cold knock, 2008 Avalanche cam shaft replaced after 35,000 miles, 2011 Chevrolet it was better than the previous except for that six speed transmission clonk in the drive train, 2021 GMC Sierra nothing but problems I have tried to get it in to the dealership for over 4 months no loaner cars available and will not offer a rental car and this all about saving the dealership money, I have a rattle noise in the dash reported to them before the warranty was up at 36K and they worked on this issue in the past said they fixed it got the truck back with same issue, since then other issues with this truck and I have passed the 36K mileage, here are the other issues, a engine whining noise, a roaring noise that sound sometimes like a wheel bearing or issues with the brake calipers on the passenger side of the truck, the back seat rattles on rough roads, down shifting to a stop the engine idles rough, the engines uses oil and the same old thing you can hear the lifters tapping especially on a cold start and I can hear the clearance of the brakes between the pads and rotors the clapping noise when applying the brakes. NEWS FLASH GMC just got off the phone with GM inquiring about a follow up on a compliant I filed about the vehicle and representative confirmed they will not be required to provide a rental car once they get it into dealership since the vehicle is outside the warranty. I paid almost 50 thousand dollars for a truck that is nothing but junk and I have driven vehicles for a long time and I may not know exactly what is wrong with one, but I know from experience things that are wrong with this truck that has just over a year old and 40k miles should not to happen if it has the quality and endurance that GM advertises. Some of these issues could be a safety issue on the highway and I have made the dealership aware of this. Do you think they have made contact with me? NO!!! No more GM Vehicles for me. I would not even give them a star if it was possible.

  • al p

    have a 2021 gmc sierra came home from work shut truck off opened door radio and lights stayed on for an hour did not shut off gm told me its a 2021 they have had problems with them

  • Jeffrey P

    I am having the exact same problems as David with stuttering at launch. Took it into GMC and they replace left back of rods. But problem is still happening. There is a service bulletin related to this problem but they can’t seem to fix it. PIP5776C

  • Mike J

    I bought my 2021 SLT MARCH 2021 5 months later I took it to the dealership because my touch screen was not working properly. 2 months later at 1200 k miles I noticed oil in my driveway under truck. Took it to the dealership they said it was a bad filter. Two months later I noticed I had a lot of oil on my under body. Took it back to the dealership and they said it was the oil pan leaking. Now the truck is missing on start up and clattering on start up. I’ve had enough with GMC products I’m gonna sell it. It has 1700K. Soon and by a KIA LOL.

  • David

    Purchased a 2021 GMC Sierra SLT in May 2021, first issue I had was the driver side Light. It had bad LED’s after complaining they replaced it 3 times. now it is fine. Next problem was at about 4,000 miles the truck started to hesitate and buck at start up feels like the trans but could also be misfire. complained dozens of times took it in and left it for days and all they said was it is normal. Took it to a different dealer and told them the story. they looked at the vehicle history and told me the dealer I purchased it from did not enter into the system all the time a I took it in for a warranty complaint and only showed my oil service records. After a few days of this dealer having it all they could say is it runs fine and until I get a engine light on there is nothing they can do. It has been two months now and every time I get into the truck and start to go it hesitates, chugs, or skips now it is starting to happen as I am driving at higher speeds.

  • joe

    2022 gmc less 500 miles hard shifting both upshifting and downshfting first complaint

  • Mike &

    What’s the noise in rear-end when going over a bump?

  • Craig

    I have a gmc 2021 , when am stopped at a light the engine will shutter like it’s going to stop , anyone know or have this kind of a problem? 5.8 v8 , Sierra , Denali pick-up

  • Trevor R

    hello i have a 2021 sierra slt 1500 harley davidson gmc truck. i purchased it 3-4 months ago. first issue was multi tailgate was working they fixed it. At 1800 miles my battery went dead had to jump start the the truck. Truck has been driving the same since had an appointment to do audio upgrades . Truck now is currently smokin and sparks are comin from under the hood . Had it towed to the nearest dealership they went to the glove box and seen 5k in audio receipts. The first thing that came out the the dealer mouth was it’s not goin to be covered over warranty. Are we allowed to upgrade our audio system can the dealership blame a 3 rd party . Can i sue the dealership he said they would take.a another look . but i don’t like that not under warranty talk

Leave a Reply or Comment Cancel Reply

Write a comment below to share online. Or, instead you can to our legal team.

Please select your star rating.

Briefly describe your experience Briefly describe your experience

What’s your name? What’s your name?

What’s your phone number? Please enter a valid phone number

Want to know if you could sue? Get a free legal evaluation Lemberg Law?

Get Your No-Obligation
Case Evaluation

Send a secure message to our legal team.

What’s your name? What’s your name?
What’s your email address? What’s your email address?
What’s your phone number? What’s your phone number?
Briefly describe the problem Briefly describe the problem
Confidentiality Guarantee: We keep your information completely confidential and will not send you spam or sell your information.
By submitting above, I agree to the privacy policy and terms and consent to be contacted by an agent via phone call or text message at the phone number(s) listed above, including wireless number(s).
Exit mobile version