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Complaints

Showing 18 of 18
Nov 18, 2025 Engine And Engine Cooling 190,000 mi

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. The contact made several attempts to restart the vehicle; however, the vehicle failed to rest...

Nov 18, 2025 Engine And Engine Cooling 190,000 mi

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. The contact made several attempts to restart the vehicle; however, the vehicle failed to rest...

Nov 9, 2023 Forward Collision Avoidance 6,700 mi

The contact owns a 2020 GMC Sierra Denali. The contact stated while driving 75 MPH, the Adaptive Cruise Control feature became inoperable. The contact stated that when the vehicle got too close to another vehicle, the Adaptive Cruise Control feature failed to activate as designed. The vehicle was no...

Nov 9, 2023 Forward Collision Avoidance 6,700 mi

The contact owns a 2020 GMC Sierra Denali. The contact stated while driving 75 MPH, the Adaptive Cruise Control feature became inoperable. The contact stated that when the vehicle got too close to another vehicle, the Adaptive Cruise Control feature failed to activate as designed. The vehicle was no...

Apr 26, 2023 Electrical System

The contact owns a 2020 GMC Sierra Denali. The contact stated while driving 65 MPH at night, the vehicle stalled and the “Shift to Neutral and Restart Vehicle” message was displayed. The contact was unable to restart the vehicle and was unable to visibly see the roadway. The contact was able to ...

Apr 26, 2023 Electrical System

The contact owns a 2020 GMC Sierra Denali. The contact stated while driving 65 MPH at night, the vehicle stalled and the “Shift to Neutral and Restart Vehicle” message was displayed. The contact was unable to restart the vehicle and was unable to visibly see the roadway. The contact was able to ...

Nov 23, 2021 Engine 20,000 mi

The contact's father owns a 2020 GMC Sierra Denali 3500. The contact stated that while his father was driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to the dealer and diagnosed with a cylinder #1 misfire. The vehicle was repaired; however, the fail...

Nov 23, 2021 Engine 20,000 mi

The contact's father owns a 2020 GMC Sierra Denali 3500. The contact stated that while his father was driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to the dealer and diagnosed with a cylinder #1 misfire. The vehicle was repaired; however, the fail...

Apr 7, 2021 Service Brakes 3,000 mi

BRAKES SQUEAK. STARTED ABOUT 3000 MILES. I HAVE COMPLAINED TO DEALER SEVERAL TIMES.

Apr 7, 2021 Service Brakes 3,000 mi

BRAKES SQUEAK. STARTED ABOUT 3000 MILES. I HAVE COMPLAINED TO DEALER SEVERAL TIMES.

Dec 16, 2020 Engine

KNOCKING COMING FROM ENGINE - NOTICEABLE UNNECESSARY NOISE IN WHICH DEALER CAN NOT FIX THE PROBLEM

Dec 16, 2020 Engine

KNOCKING COMING FROM ENGINE - NOTICEABLE UNNECESSARY NOISE IN WHICH DEALER CAN NOT FIX THE PROBLEM

Oct 29, 2020 Service Brakes 350 mi

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

Oct 29, 2020 Engine 350 mi

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

Oct 29, 2020 Service Brakes 350 mi

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

Oct 29, 2020 Engine 350 mi

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

Oct 8, 2020 Engine 2,200 mi

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.

Oct 8, 2020 Engine 2,200 mi

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.