2018 GMC Sierra 2500

35 complaints on file, page 1 of 2.

1. Filed May 9, 2026Failure May 2, 2026Henderson, NVElectrical system, Engine, Fuel/propulsion system

   GM Duramax L5P diesel engine electrical connector for #4 fuel injector. This failure caused the Diesel exhaust brake, which controls downhill speed, to disengage, extreme shaking of the vehicle, emissions system warning and speed limiting. This occurred while descending a steep grade while towing a 34 feet long, 10,000 pound trailer. This is a known issue with this diesel engine and documented in GM Technical Service Bulletin 23-NA-027. Inspection and repair at a GM dealership confirmed a known issue with the #4 injector pigtail connector caused by improper wire routing and interference wit the Sound Shield and Valve Cover Heat Shield This was a sudden failure of the #4 pigtail connector with no advance warning. In addition to violent shaking of the vehicle, multiple warnings on the DIC indicating that the Diesel Brake was disengaged, the emission system had an issue, and speed would be limited.

   NHTSA complaint 11736800
2. Filed Mar 10, 2025Failure Feb 3, 2025Miami, FLVisibility/wiper

   The component that failed is the rear glass. Yes, it is available for inspection. The rear glass defogger stopped working and melted the tabs off of the glass and burned the tabs cover. The problem has been confirmed by the dealership and i was advised there is already a recall for this but apparently my vin does not fall under the recall.

   NHTSA complaint 11647299
3. Filed Nov 10, 2024Failure Aug 31, 2022Paradise, TXElectrical system

   Service Trailer Brake System Warning From time to time, this warning goes off in the vehicle and when it does, it does it constantly. When the warning is dismissed, it does it again seconds later. If it is not dismissed, it does it again seconds later. It is a persistent three ding double chiming that is not only constant, the vehicle is doing it without a trailer connected to it. The GM dealerships we have been to regarding this issue do not know how to fix it since the warning is as intermittent as it is persistent. Once one of the dealerships was finally able to observe the warning themselves, we were told because it does not cause the check engine light to come on, they are not given a code, therefore, they do not know how to address the issue. The Service Engine Brake System warning is not only a persistent auditory nuisance. The warning chime overrides any other audio capability of the vehicle and it will be the only thing the control panel shows. If the warning is dismissed, it comes right back. This means we cannot hear anything else in the vehicle, such as turn signals, and we cannot see anything else on the control panel, such as speed. We can only surmise this issue is some sort of an electrical system malfunction since we do not have a trailer connected to the vehicle when the Service Trailer Brake System warning is coming on. The vehicle has been presenting this persistent warning since we purchased it from a dealership in August of 2022 and the vehicle continues to present this persistent warning intermittently, which will last days to weeks at a time and is not corrected by the engine being turned off and restarted, no matter if the engine is shut off for minutes or days. How much time passes between the persistent Service Engine Brake System warning events can be less than one day to several months later.

   NHTSA complaint 11624405
4. Filed Oct 9, 2024Failure Sep 26, 202448,000 milesJonesboro, LAFuel system, Diesel

   The contact owns a 2018 GMC Sierra 2500. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power. No warning light was illuminated. The vehicle was towed to the dealer, where it was determined that the fuel pump control module needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was opened. The failure mileage was approximately 48,000.

   NHTSA complaint 11618888
5. Filed Nov 7, 2023Failure Nov 6, 2023Kula, HIEngine, Fuel/propulsion system

   Metal in the fuel filter and throughout the fuel system, 38 codes on the computer just in 2 weeks after a full service again at the dealer. All service has been preformed at A GMC Dealer since truck was serviced. 1. P026D - Fuel injection Quantity “A” Higher then expected 2. P06CC - cylinder 8 incorrect 3. P133F - cylinder 8 glow plug offset exceeding learning limits None stop this is happening since [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

   NHTSA complaint 11553906
6. Filed Nov 2, 2023Failure Aug 1, 2022Kula, HIEngine, Fuel/propulsion system

   Constant issues with glow plug failures, fuel rail failure, fuel pressure failure. Truck has been in the Gmc service regarding these issues constantly for the last year with a total of five repairs and replacement of glow plugs with releaning learning new plugs and now the 6th return to the shop they’re tearing down the fuel system. Malfunction and engine light consistently come on with the same occurring problems generating from the fuel system and glow plugs. Fuel mileage is absolutely terrible and lose of power hazardous to safety!!! Gmc has issued an extended warranty for 15 years and 150,000 miles, but cant and hasn’t found a repair for vehicle and just replaces the glow plugs just so they can fail again and again!!! They need to replace everything that needs to be done and if no fix they need LEMON Law The vehicle. This is ridiculous going back to the shop every two weeks I have my truck in the shop for a month to get it back, to put it back in the shop two weeks later, to have it back in the shop for a month. Since this start 17months ago I’ve only been able to put less then 7000 miles on the vehicle because GMC constantly has the truck! The is ridiculous when you’re paying $800 a month for your payment and insurance on your vehicle that you can’t drive because the manufacturer is constantly having to repair and replace the same thing over and over again

   NHTSA complaint 11553304
7. Filed Sep 12, 2023Failure Jul 23, 2023Wilmington, NCUnknown or other, Wheels

   driving at 70mph, thread from tire blew.. That was in July, I went and purchased another tire from Bob King GMC Wilmington, NC. The first tire that blew was now discontinued so I purchased another Good Year . On Friday I noticed that another tire on my truck had a bubble along the threads again. It was also getting ready to blow like the first tire. I went to the dealer and they told me the tire I purchased (Good Year) was also discontinued... Please look into this matter.. They have faulty tires and this matter could have turned out with a death.. It isn't the dealers fault it is Good Year .... I have also read on line this isn't the first time people are complaining about the threads coming apart....

   NHTSA complaint 11544060
8. Filed Aug 21, 2023Failure Aug 20, 2023Las Cruces, NMWarnings, Electrical system, Steering

   While braking ( after being on the highway) all dash gauges turn black, radio shuts off, AC shuts off. Service Stabilitrak light comes on when dash flashes back on. While driving AC turns off, Radio turns off same stabilitrak warning flashes, speedometer turns off. Power steer control went out while trying to turn. Truck put itself in 4 wheel drive when I turned on the trailer assist. Parking assist periodically turns itself off.

   NHTSA complaint 11539836
9. Filed May 30, 2023Failure May 26, 2023West Harrison, INEngine

   Low coolant warning light came on. I was towing a travel trailer on a very busy roadway with no place to pull off while pulling a trailer. I had to pull over to the shoulder to check the coolant level and make sure I didn’t cause major damage to my engine by letting it overheat. While waiting to let the engine cool down, I researched and found that this is a very common issue with L5P Duramax Engines in GM trucks and it is specifically related to a faulty coolant level sensor. As it turns out, my coolant level was fine and there was no issue. The danger posed by me pulling over and waiting for well over an hour on the side of the busy backroad with my son in the truck was not a necessary one. It appears that this is a well known issue that is not being addressed by GM.

   NHTSA complaint 11524351
10. Filed Feb 23, 2023Failure Jan 2, 2023Star, IDElectrical system, Exterior lighting, Unknown or other

    I have a 2018 GMC Sierra Duramax Quad-Cab and when it is connected to either my boat, stock trailer, or cargo trailer the lights and electric trailer brakes on the trailers do not work. and the chime from the "Service Trailer Brake" indicator sounds and doesn't stop until I unplug my trailer harness from my truck making it a distraction and an unsafe situation when trying to navigate through traffic(changing lanes, stopping, and other functions needed when hauling trailers). The dealership said it was a module and specified which one and so I elected to replace it myself and it wasn't the issue. I choose to do the work myself as they quoted me a price of $700.00+ to repair the problem.

    NHTSA complaint 11508714
11. Filed Nov 2, 2022Failure Oct 14, 2022Ravensdale, WAElectrical system, Unknown or other

    Water leak, known in other years of the same model vehicle, caused the rear defrost to fail and smoke when in operation nearly causing a fire in the vehicle as it was being operated.

    NHTSA complaint 11491986
12. Filed Jul 15, 2022Failure Jul 15, 2022Phillipsburg, NJAutomatic transmission

    2018 GMC SIERRA 2500. CONSUMER WRITES IN REGARD TO TRANSMISSION COOLER LINES RECALL. THE CONSUMER STATED THE VEHICLE BEGAN LEAKING FLUID. THE VEHICLE WAS TAKEN TO THE DEALER TO HAVE THE VEHICLE REPAIRE, WHICH COULD NOT BE DONE THE SAME DAY. THE CONSUMER WAS SEEKING REIMBURSEMENT FOR THE HOTEL EXPENSE, SINCE THE CONSUMER WAS TRAVELING OUT OF STATE WHEN THE FAILURE OCCURED.

    NHTSA complaint 11474048
13. Filed Apr 15, 2022Failure Mar 28, 2022Cortland, OHEngine, Fuel/propulsion system

    Faulty pigtail connector for fule injectors. Cause The vehicle to shut down even while going down the highway possibly causing injury by immediate deceleration wich could cause an accident. For me on this vehicle I’ve had this happen three times and it has cost me anywhere from $800 to 1000 per injector especially if damage is done to one of the fuel injectors.

    NHTSA complaint 11460968
14. Filed Feb 14, 2022Failure Feb 14, 2022Sykesville, MDEngine

    2018 GMC SIERRA 2500 HD. CONSUMER WRITES IN REGARDS TO ACCELERATION ISSUES. THE CONSUMER STATED THE VEHICLE DISPLAYED WARNING LIGHTS. AND BEGAN SHAKING. THE VEHICLE BECAME DIFFICULT TO ACCELERATE. THE DEALER INFORMED THE CONSUMER THAT NUMBER 4 INJECTOR WAS THE CAUSE OF THE FAILURE. THE VEHICLE WAS REPAIRED. SHORTLY AFTER, THE GLOW PLUG FAILED AND THE COMPUTER REQUIRED AN UPDATE. THE CONSUMER REQUESTED TO REIMBURSED FOR THE RENTAL VEHICLE AS WELL AS REPAIR COSTS.

    NHTSA complaint 11451874
15. Filed Feb 9, 2022Failure Aug 1, 2021Mount Pleasant, PAEquipment

    The contact owns a 2018 GMC Sierra 2500. The contact received notification of NHTSA Campaign Number: 21V496000 (Equipment) however, the part to do the recall repair was not yet available. The local dealer was contacted and it was confirmed that parts were not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

    NHTSA complaint 11451143
16. Filed Dec 8, 2021Failure Oct 31, 2021Baker, FLUnknown or other

    Diesel exhaust fluid systems limited to slower speeds causing traffic back up. Issue is these components are failing on these trucks. Mine failed with in 3 yrs of manufacture date.

    NHTSA complaint 11443047
17. Filed Nov 12, 2021Failure Nov 1, 2021Golden, COEquipment

    The contact owns a 2018 GMC Sierra 2500. The contact received notification of NHTSA Campaign Number: 21V496000 (Equipment) however, the part to do the recall repair was unavailable. The local dealer was contacted, and it was confirmed that the part was not available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

    NHTSA complaint 11440272
18. Filed Oct 13, 2021Failure Oct 7, 2021Pueblo West, COVisibility/wiper

    Both the outside mirrors are loose and will fold while driving. At night if I am not aware and it is dark the mirror fails to identify vehicles in the visibility area because they vibrate closed to the door from the driving air on the mirror. I will have to pull over and push the mirror back. I have brought it to the dealer and they say they all do it. It is normal. The issues has been confirmed by the dealer. It has been present on the car for about 1 year. The internet is filled with this safety complaint. They are starting to fold when you close the door.

    NHTSA complaint 11436703
19. Filed Oct 4, 2021Failure Sep 20, 202130,600 milesClovis, CAEquipment

    The contact owns a 2018 GMC Sierra 2500. The contact received a notification for NHTSA Campaign Number: 21V496000 (Equipment) however, the part to do the recall repair was unavailable. The dealer had been notified about the recall; however, the contact was informed that the part was not yet available. The manufacturer had been notified of the recall. The contact recently stated that the check engine warning light was illuminated. The contact also stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The failure mileage was 30,600. VIN tool confirms parts not available.

    NHTSA complaint 11435349
20. Filed Sep 30, 2021Failure Aug 1, 2021Cookeville, TNEquipment

    The contact owns a 2018 GMC Sierra 2500. The contact received notification of NHTSA Campaign Number: 21V496000 (Equipment) however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer was made aware of the issue and informed the contact that parts were not available. The manufacturer was not made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts are not available.

    NHTSA complaint 11434999