2018 GMC Sierra Denali Problems
- Complaints
- 17filed with NHTSA
- Median mileage
- 28,000miles, 13 complaints with mileage
- Recalls
- 0campaigns on record
- Trend
- FallingComplaints filed in the last 3 full calendar years are at least 25% lower than in the 3 years before.
Sources: NHTSA records for the 2018 GMC Sierra Denali (complaints, recalls, investigations). Report an error
NHTSA recorded 17 consumer complaints for the 2018 GMC Sierra Denali. The part named most often is engine, with 5 complaints (29% of the total), followed by brakes (4) and body and structure (4). 13 of the complaints include a mileage, and 69% of those were filed for vehicles with under 50,000 miles; the median is 28,000 miles. Of all complaints, 1 an injury, according to the filers. NHTSA lists 0 recall campaigns and 948 technical service bulletins for this model year. Engine complaints overlap with 104 technical service bulletins filed under the same part. Brakes complaints overlap with 23 technical service bulletins filed under the same part.
This model year has fewer than 25 complaints on record, so the numbers below can change a lot with a few new reports.
Which parts are reported most
Complaints can name more than one part, so the counts add up to more than the total. Select a part to see its complaints, recalls and bulletins.
- Engine5 29%
- Brakes4 24%
- Body and structure4 24%
- Exterior lighting3 18%
- Steering3 18%
- Other or unknown1 5.9%
- Suspension1 5.9%
- Wheels1 5.9%
Example complaints
Engine: “Driving down the highway about 65mph it made a loud clunk and I took it in to service department and they told me I would have to pay about $400.00 to drain the transmission fluid and replace it. I told them m pick up only has less than 15,000 miles on it I don't think this is fair, the service gu said the don't pay for it and other Gmc denali customers had theirs done and problem was solved and I wasn't the only customer that had the issue and cory from alaska auto body said it was safe to drive”
NHTSA complaint #11385369, filed 2020-12Brakes: “I nearly died when my brakes failed on my 2018 Gmc denali this morning. I was only going 60 MPH when another driver cut in front of me, and hit their brakes but when I tried to stop, I could not! I then began swerving from lane to lane because it was raining. Thank god I didn't die and that the person on the right slowed down and moved out the way. The truck seemed to be pulling me to the right. Why I have no idea. But why is GM putting people lives at risk like this? Why are we having to suffer or put our families in jeopardy. This makes no sense. …”
NHTSA complaint #11366569, filed 2020-10, 14,700 milesBody and structure: “The rear end makes noise when turning and sometimes stoping. When weight is place on bed the rear end make noises. Something is wrong in the rear end of this truck. When truck is moving and turning you can here the noise.”
NHTSA complaint #11329880, filed 2020-06, 28,000 milesMileage when problems were reported
69% of the 13 complaints with a mileage were filed for vehicles with under 50,000 miles; the middle half falls between 14,700 and 61,000 miles.
Complaints by year filed
Trend: falling. Complaints filed in the last 3 full calendar years are at least 25% lower than in the 3 years before.
Recalls and investigations
NHTSA lists no recall campaigns for the 2018 GMC Sierra Denali in the data used here. A recall can apply to some vehicles of a model year and not others, so check a specific vehicle by VIN at nhtsa.gov/recalls.
Technical service bulletins
TSBs are manufacturer notes to dealers about known repair procedures. They are not recalls and do not by themselves mean a vehicle has a fault. 948 on record; the latest 10 are shown.
- 11037555Sep 26, 2026Other or unknown. This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.
- 11037253Sep 4, 2026Other or unknown. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
- 11035340Jul 21, 2026Other or unknown. PI to help diagnose A/C concern
- 11030974Apr 1, 2026Other or unknown. This preliminary information communicates information about how to determine if a wheel and tires size change is available.
- 11030092Mar 9, 2026Other or unknown. This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.
- 11030091Mar 9, 2026Other or unknown. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
- 11027601Jan 8, 2026Other or unknown. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
- 11025755Nov 20, 2025Other or unknown. This Preliminary Information communication provides information to the technician about vehicles that have had multiple repair attempts that are being performed on customer’s vehicles that exhibit…
- 11023091Sep 9, 2025Other or unknown. New Vehicle Monitoring Programs Section in IVH
- 11022084Aug 14, 2025Other or unknown. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
Other model years of the GMC Sierra Denali
| Year | Complaints | Median mi | Recalls | Crash ★ | MPG | Score (50 = typical) | Trend |
|---|---|---|---|---|---|---|---|
| 2020 | 11 | 20,000 | 0 | — | — | — | Not enough data |
| 2019 | 26 | 5,269 | 0 | — | — | 77 · More | Falling |
| 2018 | 17 | 28,000 | 0 | — | — | — | Falling |
| 2017 | 15 | 60,000 | 0 | — | — | — | Falling |
| 2016 | 30 | 48,000 | 0 | — | — | 50 · Typical | Falling |
| 2015 | 22 | 47,800 | 0 | — | — | — | Stable |
| 2014 | 14 | 59,496 | 0 | — | — | — | Not enough data |
| 2013 | 8 | 70,000 | 0 | — | — | — | Not enough data |
| 2012 | 10 | 50,000 | 0 | — | — | — | Not enough data |
| 2011 | 28 | 65,000 | 0 | — | — | 0 · Fewer | Falling |
| 2010 | 10 | 45,284 | 0 | — | — | — | Not enough data |
| 2009 | 7 | 94,000 | 0 | — | — | — | Not enough data |
| 2008 | 18 | 58,000 | 0 | — | — | — | Stable |
| 2006 | 5 | 61,000 | 0 | — | — | — | Not enough data |
| 2004 | 11 | 44,000 | 0 | — | — | — | Not enough data |
| 2002 | 13 | 79,315 | 0 | — | 12 | — | Not enough data |
All GMC Sierra Denali model years · Best and worst years by complaints
Frequently asked questions
How many NHTSA complaints does the 2018 GMC Sierra Denali have?
NHTSA recorded 17 consumer complaints for the 2018 GMC Sierra Denali as of Oct 30, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
What part of the 2018 GMC Sierra Denali is reported most often?
Engine is named most often, in 5 complaints (29% of the total), followed by brakes with 4.
Has the 2018 GMC Sierra Denali been recalled?
NHTSA lists no recall campaigns for this model year in the data used here. To check a specific vehicle, enter its VIN at nhtsa.gov/recalls.
At what mileage are problems with the 2018 GMC Sierra Denali reported?
Among the 13 complaints that include a mileage, the median is 28,000 miles and the middle half falls between 14,700 and 61,000 miles; 69% were filed for vehicles with under 50,000 miles.
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 30, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
Complaint counts come from NHTSA’s public complaint database; we count each complaint once. The source records for this vehicle are on nhtsa.gov. Scores and trends are our own summaries of that data, described in the methodology. This page is not legal, safety or repair advice: for a specific vehicle, check its VIN at nhtsa.gov/recalls and ask a qualified mechanic. See an error? Tell us.