YearToAvoid

2015 GMC Denali Problems, Recalls & Reliability

Verdict

Avoid

Complaint Index

100/100

#1 most-complained of 6 Denali years

The 2015 GMC Denali ranks worst of 6 model years, with a complaint index of 100 and 18 NHTSA complaints. Electrical System issues make up 50% of complaints, followed by Transmission & Powertrain at 28%. No recalls have been issued for this year.

Complaints
18
Recalls
0
Crashes / fires
1 / 0
Injuries / deaths
1 / 0
NHTSA overall rating
Not rated
EPA combined MPG
—

Top 2015 GMC Denali problems

NHTSA owner complaints by component group. Groups with 15+ complaints have their own page.

  1. Electrical System9 (50%)
  2. Transmission & Powertrain5 (28%)
  3. Brakes3 (17%)
  4. Engine2 (11%)
  5. Steering2 (11%)
  6. Fuel System1 (6%)
  7. Other1 (6%)
  8. Structure & Body1 (6%)
  9. Suspension, Wheels & Tires1 (6%)
  10. Visibility & Wipers1 (6%)

What owners report

  • Rear taillights collect moisture and fail repeatedly, even after dealer replacement, around 48,000 to 50,000 miles.
  • Both LED brake lights fail intermittently, working briefly when tapped but going out again while driving.
  • The transmission hesitates from a stop, then engages with a loud, violent shift, followed by shuddering, slipping, and jerking between gears at around 44,415 miles.
  • Brakes require excessive pedal force and fail to stop the vehicle promptly, in one case leading to a rear-end crash at 73,000 miles.
  • The stability light illuminates alongside a sudden loss of power, unexpected shift into four-wheel drive, and dashboard warning lights, leaving the vehicle stuck in neutral at 39,000 miles.
  • Power steering intermittently fails during low-speed turns, reported at 72,000 miles.
2015 GMC Denali complaints: complaints filed per month3Apr 2017Jul 2018May 2019Feb 2020May 2020Aug 2020Dec 2020
26 complaints filed with NHTSA from Apr 2017 to Feb 2021; peak Aug 2017 (3).

2015 GMC Denali recalls

No safety recalls on record for this model year.

2015 compared with other Denali years

Complaint Index by model year (0 = fewest issues, 100 = most)0255075100201020112012201320142015
Complaint Index: 0 = fewest issues, 100 = most, relative to other years of this model. Avoid Caution Good Best
YearVerdictIndexComplaintsRecallsMPG
2013Best2050—
2014Good4050—
2015Avoid100180—

All GMC Denali years: best and worst →

Frequently asked questions

Is the 2015 GMC Denali reliable?
Based on NHTSA owner complaints and recalls, the 2015 Denali has a complaint index of 100 and ranks worst among the 6 model years with data, making it the year to avoid within this model lineup.
What is the most common problem with the 2015 GMC Denali?
Electrical System complaints are most common, accounting for 50% of all reported issues, with a median failure mileage of 50,000 miles.
Does the 2015 GMC Denali have any recalls?
NHTSA lists no recalls for the 2015 GMC Denali.
How many complaints does the 2015 GMC Denali have?
NHTSA has logged 18 complaints for the 2015 GMC Denali, including 1 crash and 1 injury, with no reported fires.
What year GMC Denali should I avoid?
Among the 6 model years with data, 2015 has the highest complaint index at 100 and ranks worst, while 2010 ranks best with a complaint index of 0.

Sources: NHTSA Office of Defects Investigation complaint and recall databases; U.S. EPA fuel economy data; NHTSA 5-Star Safety Ratings. Complaints are unverified owner reports.

Data updated Sep 24, 2026. Read the methodology and data sources. The Complaint Index is based on NHTSA owner complaints and recalls; it is not a reliability rating.