2014 GMC Sierra Problems

What owners report

Owners of this model year most often write about the headlights: complaints describe low-beam and high-beam output that they find too dim and too narrow for unlit roads, reported within the first few hundred miles of ownership and often raised with the dealer at the first service. A smaller group describes delayed acceleration or transmission slip when pulling away or merging, a vibration at steady highway speed, and airbags that did not deploy in a crash.

1. 1
   Exterior lighting

   Headlights too dim for unlit roads at night

   • 60 complaints (59%)
   • median 600 mi at 1.0 yrs old (48 state mileage)
   • 1 mention a crash, fire or injury
   • filed 2014–2016

   Complaints describe projector headlights that light only a short distance ahead and give little illumination to the sides of the road, with the high beam adding reach mostly above the roadway rather than down it. Owners say the problem is most noticeable on dark rural roads, in rain, and on curves, and several mention running the fog lights continuously to compensate. According to the complaints, dealers often said the lights were aimed or operating as designed; a few owners report bulb replacement and a body control module reflash under a service bulletin, with mixed results. Mostly reported at very low odometer readings, many under 1,000 miles and often within the first months of ownership, with a few filed later in the vehicle's life.

   2 related service bulletins

   What to check: Drive the truck on an unlit road at night before buying, and ask whether the bulb replacement and body control module reflash described in the headlight service bulletins was ever performed. Also check both headlamp lenses for trapped condensation.

   2 excerpts from owner complaints in NHTSA records

   “The vehicle lights are very dim even with the high beams on. While driving at night can barely see in front of me. These are a hazard to me and others, since not being able to see a good distance in front of the vehicle makes hard to see pedestrians, animals or debris in the road at night.”

   NHTSA complaint #10855440, filed 2016-04, 9 miles

   “My complaint is with the how dim the oem headlights are. I have complained to Gmc regarding the headlights and the response is that they are ok with how dim the lights are. Compared to other vehicles I own/have owned the headlights are extremely dim to the point of being dangerous.”

   NHTSA complaint #10678353, filed 2015-01, 50 miles
2. 2
   Transmission and drivetrain

   Delayed acceleration and transmission slip on pull-away

   • 5 complaints (5%)
   • median 1,500 mi at 0.6 yrs old (4 state mileage, few)
   • filed 2014

   Complaints describe a pause when the accelerator is pressed from a stop or after braking, with the engine hesitating before the truck moves, and in some cases the transmission slipping or refusing to drop into a passing gear so the engine runs up against the rev limiter. Owners say the condition appears when pulling into traffic or merging. According to the complaints, dealers either could not reproduce the concern or said the vehicle was operating to specification. Reported at low mileage, generally within the first few thousand miles of ownership.

   1 related service bulletin

   What to check: On the test drive, accelerate from a stop and from a rolling brake-to-throttle transition, and note any delay before the truck responds. Ask whether any transmission diagnostics or solenoid-related bulletin work was performed.

   2 excerpts from owner complaints in NHTSA records

   “Vehicle was purchased new from a dealership. The vehicle is modified and sold commercially under the rmt (rocky mountain truck works) package. The package includes modified suspension and lighting. When accelerating, the transmission fails to shift into a passing gear causing the RPM(s) to exceed 6000 at which point the rev limiter shuts down power to the vehicle until the RPM(s) are back in a safe operating limit. The first time this happened, I was attempting to pass a vehicle on a secondary two lane highway. …”

   NHTSA complaint #10598620, filed 2014-06, 1,000 miles

   “Brake and then accelerate losses power transmission slips. When trying to merge to freeway I brake and then try to accelerate it looses power transmission slips.”

   NHTSA complaint #10592945, filed 2014-05, 165 miles
3. 3
   Suspension

   Vibration at highway speed and steady throttle

   • 6 complaints (6%)
   • median 2,875 mi at 0.8 yrs old (6 state mileage, few)
   • filed 2013–2015

   Complaints describe a shake felt through the truck at steady speeds, sometimes strong enough to move the center console or rear window, and in one case a rumble-strip-like vibration at a particular engine speed. Owners say tires were rebalanced and the driveshaft rotated without a lasting fix. According to the complaints, dealers described the vibration as normal operation or suggested driving outside the affected speed range. Described from delivery mileage up to roughly 15,000 miles, typically at highway speeds or a steady cruise.

   What to check: Test drive at highway speed and hold a steady throttle at several speeds to feel for shake, and ask whether tires or the driveshaft have already been balanced or indexed.

   2 excerpts from owner complaints in NHTSA records

   “When we took our new truck for a test drive we noticed a vibration. The dealership supposedly checked it out and took care of it. When took delivery of the truck and drove it home the vibration was better at a slower speed but increased as the speed increased. We returned the truck to the dealership and they checked it out and said that they balanced the tires and rotated the driveshaft 180 degrees. It seem to be a little better. …”

   NHTSA complaint #10648621, filed 2014-10, 100 miles

   “My vehicle started with a vibration on or around 12,000 miles. The vibration slowly increased as time went on. I made appointment with the dealership where the vehicle was purchased.(capitaland motors) at this time the vibration was strong enough to vibrate the back window. It would start at 30mph and get worse at 45mph. The mechanic checked balance and road force the tires. But told me that the vibration was normal and he could fix my back window. I called Gmc and filed a complaint. They told me to take it to another dealership. …”

   NHTSA complaint #10672331, filed 2015-01, 15,318 miles
4. 4
   Air bags

   Airbags fail to deploy in a crash

   • 5 complaints (5%)
   • median 29,898 mi at 1.7 yrs old (5 state mileage, few)
   • 4 mention a crash, fire or injury
   • filed 2014–2023

   Complaints describe frontal impacts where the airbags did not deploy, with occupants reporting injuries; a few mention white smoke or residue in the cab. In one case the driver's airbag is described as releasing smoke without fully inflating, and a seat belt retractor came apart. According to the complaints, most vehicles were not diagnosed afterwards, and in one case the manufacturer was notified and a case file opened. Described in crashes from a few thousand miles up to about 100,000 miles.

   What to check: Ask whether the truck has been in a reported crash and whether the airbag system was inspected or the airbag-related recall completed; have a shop confirm no stored airbag fault codes and that the seat belt retractors operate normally.

   2 excerpts from owner complaints in NHTSA records

   “My son and I were driving my Gmc Sierra 2014 to his friends house before we crashed. My son was driving and has his learner's permit, however, had been driving for 4 months. At a fork in the road I told my son quickly to make a right rather than left and we crashed into an improperly grated wall of dirt causing the truck to go from 40 MPH to 0 with my son having his seatbelt on, but I did not. Neither airbags deployed and both of us sustained serious injuries. …”

   NHTSA complaint #10621127, filed 2014-08, 4,000 miles

   “I was stopped at a red light behind 2 other vehicles. A vehicle from behind struck me at appx 40 MPH and rammed me into vehicle in front of me. The cab of my truck filled with a white. Smoke . I was told by both firemen and wrecker driver airbags had activated but not deployed. My wife was with me. Both our seatbelts locked up as they should. Concern is had the airbag deployed it might have helped with back and shoulder injury. Maybe we would not have bounced around as much. …”

   NHTSA complaint #10561907, filed 2014-01, 6,000 miles

Buying note. The headlight complaints dominate this model year, so plan a night test drive on an unlit road and ask about the headlight service bulletin work before committing. Also drive at highway speed and from a stop to check for the vibration and delayed-acceleration symptoms owners describe, and confirm any open recalls were completed.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.