2018 GMC Sierra 2500 Problems
Owner-reported complaints filed with NHTSA, grouped by component
Data refreshed
What this page shows
Everything below is an owner-reported complaint submitted to NHTSA about the 2018 GMC Sierra 2500, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Reports by component
Ranked by how many owner reports name each component category
- Engine819.5%
- Electrical717.1%
- Fuel system614.6%
- Other / unspecified512.2%
- Exterior lighting49.8%
- Tires & wheels37.3%
- Visibility24.9%
- Powertrain (other)24.9%
- Steering12.4%
- Seat belts12.4%
- Transmission12.4%
- Driver assistance12.4%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Each component in detail
What the reports in each category say, in the owners' own words
Engine
Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components.
From owner reports, verbatim
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.
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)
Electrical
Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.
From owner reports, verbatim
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.
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Fuel system
Reports naming fuel storage or delivery — tanks, pumps, lines, injectors and fuel leaks.
From owner reports, verbatim
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.
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Other / unspecified
Reports whose component NHTSA recorded as unknown, or that do not map to one of the categories above.
From owner reports, verbatim
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....
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Exterior lighting
Reports naming headlights, tail lights, turn signals and other exterior lighting.
From owner reports, verbatim
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.
HEADLIGHT SHAKES AND FLICKERS WHILE DRIVING OVER BUMPS IN THE ROAD. HAPPENS ON CITY STREETS AND HIGHWAYS. FLICKERING IS VERY DISTRACTING AND DRAWS ATTENTION AWAY FROM YOUR SURROUNDINGS.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Tires & wheels
Reports naming tires, wheels, hubs, or the tire-pressure monitoring system.
From owner reports, verbatim
LT265 60 R20 Goodyear Wrangler SR-A tire experienced a tread separation while traveling at 68 MPH. This resulted in significant vibration in the steering. This tire was inspected at a tire shop and the tread separation was confirmed. The tire still had 7/32 of tread left at the time of the failure. There were no prior indications of the eminent failure of the tire. This was the SECOND of two Goodyear Wrangler tire failures for tread separation within 300 mile of each other.
LT265 60 R20 Goodyear Wrangler SR-A tire experienced a tread separation while traveling at 68 MPH. This resulted in significant vibration in the steering. This tire was inspected at a tire shop and the tread separation was confirmed. The tire still had 7/32 of tread left at the time of the failure. There were no prior indications of the eminent failure of the tire. This was the first of two Goodyear Wrangler tire failures for tread separation within 300 mile of each other.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Visibility
Reports naming windshields, glass, wipers, defrosters and mirrors.
From owner reports, verbatim
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.
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Powertrain (other)
Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials.
From owner reports, verbatim
WHILE TRYING TO MERGE ONTO THE INSTERSTATE MY TRUCK STARTED LOST POWER AND STARTED TO CHUG. MY TRUCK SLOWED DRASTICALLY WHICH CAUSED A TRACTOR/TRAILER TO ALMOST RUN INTO THE BACK OF ME. THIS HAS BEEN AN ONGOING ISSUE THAT MY DEALERSHIP HAS ADDRESSED BY REFLASHING MY COMPUTER. TO MY KNOWLEDGE THE FIRST FLASH WAS FOR THE TRANSMISSION AND THE SECOND TIME WAS FOR THE FUEL INJECTORS. THE REPROGRAMMING HAS NOT FIXED THE ISSUE. I WAS TRYING TO MERGE WITH TRAFFIC ON I 80 IN UTAH
TRUCK BEGAN ROLLING DOWNHILL WHILE THE VEHICLE WAS IN PARK WITH THE KEYS OUT OF TGE IGNITION. I WAS REMOVING A CHILD SEAT FROM THE PASSENGER SIDE REAR SEAT AT THE TIME. SPOUSE WAS ABLE TO HURRIEDLY JUMP INTO THE VEHICLE AND APPLY THE BRAKES.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Steering
Reports naming the steering system — racks, columns, power-steering assist and steering linkage.
From owner reports, verbatim
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Seat belts
Reports naming seat belts, buckles, retractors and pretensioners.
From owner reports, verbatim
THE PASSENGER SEAT HAS NO WARNING SYSTEM IF THE SEAT BELT IS NOT BUCKLED. ON THIS VEHICLE ONLY THE DRIVER HAS A WARNING FOR AN UNBUCKLED SEAT BELT. *TR
Too few reports in this category for a page of its own — they appear in the full complaint list.
Transmission
Reports naming the automatic or manual transmission, including shifting behaviour, shudder, slipping and transmission control modules.
From owner reports, verbatim
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Driver assistance
Reports naming forward-collision avoidance, lane keeping, back-over prevention, cruise control and related electronic driver-assistance systems.
From owner reports, verbatim
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Elsewhere on this vehicle
Data sources
- NHTSA Office of Defects Investigation — owner-reported complaints and the components recorded on them
Data on this page last refreshed .