Is the 2018 GMC Sierra 1500 a bad year?
305 owner complaints to NHTSA. Transmission complaints: 131, 13× a quiet Sierra 1500 year.
Keep it, but watch the transmission
Half of the transmission complaints for this year were filed at 13k–68k miles, where you are now. Few of them say the car was towed: 6 of 131 filed since 2016.
The verdict moves with mileage: the same car reads differently at 30,000 and at 150,000 miles.
What 2018 Sierra 1500 owners report, by mileage
Each system owners named in five or more complaints, with the mileage range where the middle half of those complaints were filed. Read at 32,000 miles.
| SYSTEM | COMPLAINTS | MIDDLE HALF FILED AT | TYPICAL US REPAIR BILLS |
|---|---|---|---|
| Transmission and drivetrainSTANDS OUT | 131 (43%) | 13k–68k miles · around this mileage | CV axle / CV joint replacement (one side) $300–$1,500 · Automatic transmission replacement $2,500–$7,000 |
| BrakesSTANDS OUT | 44 (14%) | 5k–40k miles · around this mileage | Brake pad replacement (one axle) $115–$390 · Brake pads and rotors replacement (one axle) $200–$1,084 |
| Electrical system | 43 (14%) | 3k–55k miles · around this mileage | 12-volt battery replacement $100–$400 · Starter motor replacement $350–$1,200 |
| Steering | 30 (10%) | 4k–32k miles · around this mileage | Steering rack and pinion replacement $700–$2,100 |
| Engine | 71 (23%) | 34k–87k miles · ahead | Valve cover gasket replacement $110–$500 · Timing chain replacement $1,000–$4,000 |
| Fuel system | 11 (4%) | too few with a mileage | — |
| Suspension | 11 (4%) | too few with a mileage | — |
| Air bags | 8 (3%) | too few with a mileage | — |
| Wheels | 7 (2%) | too few with a mileage | — |
| Body structure | 6 (2%) | too few with a mileage | — |
| Collision avoidance | 6 (2%) | too few with a mileage | — |
| Speed control | 6 (2%) | too few with a mileage | — |
| Visibility and wipers | 6 (2%) | too few with a mileage | — |
| Seat belts | 5 (2%) | too few with a mileage | — |
Bills are typical US ranges from the sources named in the tool (J.D. Power, Kelley Blue Book, CarParts.com and others), printed only for systems that stand out or sit at or ahead of 32,000 miles. Not a quote.
What owners reported alongside their complaints
Of 305 complaints: 10 mention a crash · 1 mentions a fire · 5 report an injury · 12 say the car was towed.
35 complaints were filed in the last 12 months, the newest in Oct 2026.
Counts of what owners wrote in their complaints, not verified by anyone.
In owners' own words
While under power and driving, the truck experiences noticeable vibrations that seem to come from the drivetrain.
While the truck is in motion and when accelerating around 15-20 MPH the transmission will sometimes "Hunt" For a gear causing the truck to not accelerate.
Hard shifting that started around 40000 miles and has progressively gotten worse. The same thing happened to my 2017 Chevrolet silverado 1500 and at 90000 miles that vehicle's #3 sensor in the transmission failed.
Unedited excerpts from complaints filed with NHTSA, chosen by mileage (nearest 32,000 miles), not by content. Unverified.
Recalls for the 2018 GMC Sierra 1500: 7
The left-side or right-side roof rail air bag (RRAB) inflator end cap may detach from the inflator or the inflator sidewall may rupture. A detached end cap or inflator rupture can allow compressed gas to escape and project the end cap or fragments of the inflator into the vehicle, increasing the risk of injury.
The left or right-side roof rail air bag (RRAB) inflator end cap may detach from the inflator or the inflator sidewall may rupture. A detached end cap or inflator rupture can allow compressed gas to escape and project the end cap or fragments of the inflator into the vehicle, increasing the risk of injury.
The left or right-side roof-rail air bag (RRAB) inflator end cap may detach from the inflator or the inflator sidewall may rupture. A detached end cap or inflator rupture can allow compressed gas to escape and project the end cap or fragments of the inflator into the vehicle, increases the risk of injury or crash.
The left or right-side roof-rail air bag (RRAB) inflator end cap may detach from the inflator or the inflator sidewall may rupture. A separated inflator end cap or inflator rupture can allow compressed gas to escape, resulting in the end cap or other components being propelled into the vehicle, increasing the risk of injury or crash.
The output of the mechanical vacuum pump can decrease over time, decreasing the amount of vacuum/power brake assist. A decrease in brake assist can increase the brake pedal effort and distance required to stop the vehicle, increasing the risk of a crash.
If a wheel-speed sensor fails, while the vehicle is traveling between 41 and 60 mph in four-wheel or automatic mode, the Electronic-Brake Control Module (EBCM) software may activate the driveline-protection system. Unintended activation of the driveline-protection system will cause unintended braking on the wheel on the opposite side of the failed sensor, causing the vehicle to pull to one side unexpectedly, increasing the risk of a crash.
The amount of vacuum created by the vacuum pump may decrease over time. As the vacuum level drops, the brake assist decreases, increasing braking effort, extending the distance required to stop the vehicle, thereby increasing the risk of a crash.
A recall may cover only some cars of a model year; the campaign size counts every model and year it lists. Enter your VIN at nhtsa.gov/recalls: dealers fix open recalls free.
Service bulletins from GMC: 433
Repair instructions GMC sent its dealers for symptoms seen in the shop on the 2018 GMC Sierra 1500. Ask a dealer or mechanic for a bulletin by its number.
Engine related shudder
Normal transmission shift condition and the delay in throttle response when the throttle plate is opened rapidly and advises the customer that it is normal…
Diagnostic aids for a no start or DTC'S following a transmission replacement
Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares
Neighbouring years
2017 Sierra 1500: 357 complaints, keep it, but watch the transmission · 2019 Sierra 1500: 661 complaints, consider selling.
Every GMC Sierra 1500 year
2000 · 2001 · 2002 · 2003 · 2004 · 2005 · 2006 · 2007 · 2008 · 2009 · 2010 · 2011 · 2012 · 2013 · 2014 · 2015 · 2016 · 2017 · 2018 · 2019 · 2020 · 2021 · 2022 · 2023 · 2024 · 2025 · 2026 · All Sierra 1500 years side by side
Other GMC models: GMC Acadia · GMC Canyon · GMC Denali · GMC Envoy · GMC Envoy XL · GMC Envoy Xuv · GMC Jimmy · GMC Safari · GMC Savana · GMC Sierra · GMC Sierra 2500 · GMC Sierra 3500 · GMC Sierra Denali · GMC Sonoma · GMC Terrain · GMC Yukon · GMC Yukon Denali · GMC Yukon Denali XL · GMC Yukon XL · GMC Yukon XL 1500. All makes and models.
Questions
Is the 2018 GMC Sierra 1500 a bad year?
305 owner complaints to NHTSA. Transmission complaints: 131, 13× a quiet Sierra 1500 year. At 32,000 miles the tool says: Keep it, but watch the transmission. Half of the transmission complaints for this year were filed at 13k–68k miles, where you are now. Few of them say the car was towed: 6 of 131 filed since 2016.
What are the most common problems with the 2018 GMC Sierra 1500?
By owner complaints to NHTSA: transmission and drivetrain (131), brakes (44), electrical system (43), steering (30), engine (71). Half of the transmission complaints were filed between 13k–68k miles.
How many recalls does the 2018 GMC Sierra 1500 have?
7 recall campaigns list this model year: Air bags (NHTSA 26V-325), Air bags (NHTSA 26V-166), Air bags (NHTSA 25V-432), Air bags (NHTSA 24V-756) and more. A recall may cover only some cars; check by VIN at nhtsa.gov/recalls.
Method: counts of unverified owner complaints filed with NHTSA, compared only with other years of the same model (sales volumes are unknown, so no failure rate is computed). A system stands out at 40+ complaints and at least twice the model's quiet (lower-quartile) year, or twice the share across every vehicle of that model year. The mileage range is the 25th to 75th percentile of the mileages owners reported. Data received by NHTSA through November 5, 2026. Repair prices are typical US ranges from named sources, not quotes. Not a diagnosis and not financial advice. PulsCar is not affiliated with NHTSA. Check this car at your own mileage.