2020 GMC Sierra Denali
Only 9 complaints on file — too few for a fair verdict.
This verdict reflects complaint volume compared to this model's typical year. Recalls and safety issues below apply regardless of the verdict — always check them.
Only 9 complaints on file — too few for a fair verdict. The data below is complete but unranked.
COMPLAINTS PER YEAR
View as data table
| Year | Complaints |
|---|---|
| 2002 | 13 |
| 2004 | 11 |
| 2005 | 4 |
| 2006 | 5 |
| 2007 | 1 |
| 2008 | 18 |
| 2009 | 7 |
| 2010 | 10 |
| 2011 | 28 |
| 2012 | 10 |
| 2013 | 8 |
| 2014 | 14 |
| 2015 | 22 |
| 2016 | 30 |
| 2017 | 14 |
| 2018 | 17 |
| 2019 | 26 |
| 2020 | 9 |
KNOWN PROBLEM AREAS
Only 9 complaints on file for this model year -- too few to rank by share. Raw counts only, below.
5 of 9 total reports mention: engine.
Show complaint excerpts
The contact owns a 2020 GMC Sierra 1500 Denali. The contact stated that while parking the vehicle, there was an abnormal grinding sound coming from the engine. There was no warning light illuminated.
NHTSA ODI report, 20260616
TWO ISSUES BROKEN VALVE SPRING CAUSED ENGINE TO SHUT DOWN, SECOND SERVICE BRAKE, BRAKE FAILURE LIGHT, SERVICE ESC, SERVICE TRAILER BRAKE MESSAGES CAUSING BRAKE FAILURE
NHTSA ODI report, 20201029
I NOTICED SEVERAL SPOTS OF OIL ON MY DRIVEWAY, I THEN INSPECTED THE UNDERSIDE OF THE ENGINE (L5P) AND NOTICED OIL DRIPPING FROM SEVERAL BOLTS AND LINES. MY VEHICLE, A 2020 2500HD DENALI DIESEL, HAS ONLY 2,200 MILES ON IT FROM NORMAL HIGHWAY DRIVING.
NHTSA ODI report, 20201008
2 of 9 total reports mention: service brakes.
Show complaint excerpts
TWO ISSUES BROKEN VALVE SPRING CAUSED ENGINE TO SHUT DOWN, SECOND SERVICE BRAKE, BRAKE FAILURE LIGHT, SERVICE ESC, SERVICE TRAILER BRAKE MESSAGES CAUSING BRAKE FAILURE
NHTSA ODI report, 20201029
1 of 9 total reports mentions: forward collision avoidance.
Show complaint excerpts
The contact owns a 2020 GMC Sierra Denali. The contact stated while driving 75 MPH, the Adaptive Cruise Control feature became inoperable.
NHTSA ODI report, 20231109
1 of 9 total reports mentions: engine and engine cooling.
Show complaint excerpts
The contact owns a 2020 GMC Sierra Denali. The contact stated that while stopped at a traffic light with the brake pedal depressed, the vehicle shut off unexpectedly. There was no warning light illuminated.
NHTSA ODI report, 20251118
1 of 9 total reports mentions: electrical system.
SAFETY TIMELINE
No recalls on file for this model year.
BUY-SMART CHECKLIST
2020 GMC Sierra Denali — pre-purchase inspection
- Test/inspect for engine issues (5 reports on file for this year).
- Test/inspect for service brakes issues (2 reports on file for this year).
- Test/inspect for forward collision avoidance issues (1 reports on file for this year).
FAQ
Is the 2020 GMC Sierra Denali reliable?
There isn't enough NHTSA complaint data on file yet to give this model year a verdict.
What are the most common problems with the 2020 GMC Sierra Denali?
The most-reported component is engine, accounting for 56% of complaints on file.
How many recalls does the 2020 GMC Sierra Denali have?
No recalls are on file for this model year.
Data updated 2026-07-11 · Complaints are unverified owner reports filed with NHTSA, not independently verified defects. Methodology.