2020 GMC Sierra 1500 problems and complaints
Owners have filed 465 complaints with NHTSA about the 2020 GMC Sierra 1500. The most-reported areas: Engine (232), Power Train (96), Electrical System (79).
Key takeaways
- 465 owner complaints on file with NHTSA.
- 12 involve a crash, 5 a fire, 13 reported injuries.
- Complaints are unverified owner reports; recalls are confirmed defects.
| Component | Complaints | Share |
|---|---|---|
| Engine | 232 | 50% |
| Power Train | 96 | 21% |
| Electrical System | 79 | 17% |
| Service Brakes | 53 | 11% |
| Unknown Or Other | 44 | 9% |
| Steering | 37 | 8% |
| Fuel/Propulsion System | 26 | 6% |
| Engine And Engine Cooling | 19 | 4% |
| Suspension | 18 | 4% |
| Forward Collision Avoidance | 14 | 3% |
| Structure | 13 | 3% |
| Visibility/Wiper | 12 | 3% |
One complaint can name several components, so shares add up to more than 100%.
| Version | Overall | Front | Side | Rollover |
|---|---|---|---|---|
| 2020 GMC Sierra 1500 PU/CC 4WD | 4/5 | 4/5 | 5/5 | 4/5 |
| 2020 GMC Sierra 1500 PU/EC 4WD | 5/5 | 4/5 | 5/5 | 4/5 |
| 2020 GMC Sierra 1500 PU/RC 4WD | 5/5 | 4/5 | 5/5 | 4/5 |
| 2020 GMC Sierra 1500 PU/CC 2WD | 4/5 | 4/5 | 5/5 | 4/5 |
Latest complaints, as filed
Owner-written and unverified by NHTSA.
Unknown Or Other,engine,fuel/Propulsion System - filed 2026-09-19
Vehicle: 2020 GMC Sierra 1500 SLT VIN: 3GTU9DEL5LG340438 Engine: 6.2L V8, RPO L87 Mileage: approximately 129,854 miles My 2020 GMC Sierra 1500 equipped with the L87 6.2L V8 experienced an engine failure and has been diagnosed as needing an engine replacement. I am reporting this because my vehicle is equipped with the ...
Power Train,electrical System,engine - filed 2026-09-15
5/5/25 woke up back seat entire truck flooring soaking wet back glass cracked. 4/8/25 transmission went out 117,000 miles 7/3/25 exhaust leak and placed nox 1. 7/8/25 127551 mileage exhaust leak replace gaskets, belt , tensioner, and pulley, 6/8/2025 3 knock sensors replaced and replaced intake manifold.
Engine - filed 2026-09-15
Timing in engine is going out at 150,000 miles
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More for the 2020 GMC Sierra 1500
Complaints are reports filed by owners with the National Highway Traffic Safety Administration. NHTSA publishes them without verifying them, and counts rise with how many cars were sold, so compare years of the same model rather than different models. Crash ratings are NHTSA's own 5-Star Safety Ratings results.