2015 GMC Sierra Denali

Routine

Owners filed 22 complaints about this vehicle with federal regulators, most often about the service brakes. No safety recall has been issued.

What fails
ComponentReportsCrashesFiresInjuries
Service Brakes7
000
Power Train4
000
Electrical System3
100
Unknown or Other2
000
Structure › Body › Roof and Pillars1
000
Steering1
000
Fuel System, Diesel1
000
Engine and Engine Cooling1
000
Engine1
000
Air Bags1
000

What owners reported

Newest filings
Fuel System, Diesel
Filed Dec 1, 2025160,000 milesMN

The contact owns a 2015 GMC Sierra 2500 Denali. The contact stated that while driving at 65 MPH, the vehicle lost motive power with the “Engine Power Failure” warning light illuminated. The vehicle was towed to the residence. The vehicle was later towed to an independent mechanic, where it was diagnosed and determined that the fuel system had failed and there were metal shavings in the fuel system. The contact was informed that the fuel system needed to be replaced. The vehicle was not repaired. The dealer was contacted; however, the vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline for assistance. The approximate failure mileage was 160,000.

Engine and Engine Cooling
Filed May 22, 2025FL

See attached document for complaint.

Power Train
Filed Mar 8, 2024SC

The contact owns a 2015 GMC Sierra 1500 Denali. The contact stated that while shifting the vehicle from park(P) to drive(D), the vehicle hesitated and then jerked into gear. The contact stated that the entire vehicle was shaking when it jerked into gear. The contact stated that the failure was also occurred while shifting the vehicle into reverse(R). Additionally, the failure occurred while slowing down for a traffic signal. The contact stated that the failure was a constant. The contact stated she had not noticed any warning lights during the failure. The contact had taken the vehicle to a local dealer who advised the contact that there were no open recalls for the transmission on the VIN. The vehicle was not diagnosed. The vehicle was not repaired. The manufacturer was not informed of the failure. The failure mileage was unknown.

Service Brakes
Filed Dec 30, 202030,000 milesTN

4 MONTHS AGO THE DISPLAY PORTRAYED A MESSAGE STATING, TRAILER BRAKE WARNING, HAVE SYSTEM CHECKED. SINCE THAT TIME I HAVE ATTEMPTED ON NUMEROUS TO HAVE MY VEHICLE CHECKED. BUT AS OF THIS DATE I HAVE NOT BEEN TO HAVE ANY DEALERSHIP LOOK AT MY VEHICLE. I HAVE BEEN TOLD BY DEALERSHIP THAT THE VEHICLE COMPUTER SHOWS A HISTORY BUT NO CURRENT ERROR CODES, AND THEY CAN NOT WORK ON VEHICLE UNTIL IT HAS CURRENT CODES. SO I HAVE A TRUCK THAT IS DESIGNED TO TOW CARGO/VEHICLE BUT I AM NOT ABLE TO USE MY TRUCK FOR THAT PURPOSE BECAUSE OF THIS WARNING MESSAGE. I HAVE CONTACTED DEALERSHIPS, CUSTOMER SERVICE WITH GMC AND EVEN FILED A COMPLAINT WITH TENNESSEE DEPT OF CONSUMER AFFAIRS, BUT NO ONE WANTS TO HELP WITH MY PROBLEM. I HAVE NOTICED ON THE INTERNET THAT I AM NOT THE ONLY ONE WITH THIS ISSUE. DANGEROUS SITUATION SHOULD SOMEONE USE VEHICLE TOWING. BIGGEST PROBLEM GM DOES NOT WANT TO EVEN ACKNOWLEDGE THAT THEY HAVE A PROBLEM.

Unknown or Other
Filed Aug 18, 202057,000 milesCO

AC BLOWS HOT AIR QONT GOLD FREON FOR LONGER THEN WEEK AND HALF AND IS BACK TO HOT AIR..LEAD TO BELIEVE ITS THE AC CONDENSER HAS FAILED

Service Brakes
Filed Feb 9, 202039,500 milesOH

I WAS BACKING UP AT VERY LOW SPEED THE BRAKE PEDAL GOT VERY HARD AND THE VEHICLE ACTED LIKE IT DID NOT WANT TO STOP I HAD TO KEEP PUSHING EXTREMELY HARD ON TO THE BREAK TO GET THE VEHICLE TO STOP I TRIED IT AGAIN IN DRIVE AND THE VEHICLE DID THIS EXACT SAME THING THIS TIME I NOTICED AFTER PAYING PARTICULAR ATTENTION THAT THE BRAKES WHILE THEY WERE HARD TO PRESS WERE PULSATING SO I HAD TO USE EXTREME LEG PRESSURE TO STOP THE VEHICLE. MY TRUCK HAS ALREADY HAD THE RECALL FOR THE SAME ISSUE EARLIER THIS YEAR. WHEN THIS 1ST HAPPENED IT ALMOST CAUSED ME TO WRECK INTO A FENCE

Power Train
Filed Dec 5, 20193,977 milesCA

TRANSMISSION IS NOT ABLE TO BE FIXED. THREE REPAIRS AND GM CAN'T FIX. TRANSMISSION JERKS, SLIPS, CLUNKS. UNCOMFORABLE TO DRIVE. I AM STUCK WITH SUBPAR VEHICLE. GM HAS BEEN HORRIBLE TO WORK WITH. 17 RECALLS? WHY CANT GM MAKE A SOLID RELIABLE VEHICLE AFTER 100 YEARS IN BUSINESS?

Service Brakes
Filed Feb 26, 201949,000 milesMA

HARD BRAKE PEDAL WITH INCREASED EFFORT NEEDED TO DEPRESS THE BRAKE PEDAL. FEELS LIKE TRUCK WILL NOT STOP. HAD TO HAVE TRUCK TOWED. REPORTED BACK ON 11-24-18 TO NHTSA: ( #1115347). BRAKE VACUUM PUMP WAS REPLACED @ GM DEALER ON 11-14-18, SAME SITUATION HAPPENED AGAIN ON 02-19-19. GM TSB # PIT5361D NEEDS TO BE A RECALL.

Power Train
Filed Feb 17, 201955,000 milesVT

WHEN COMING TO A STOP, APPLYING A STEADY AMOUNT OF BRAKE PRESSURE THE TRANSMISSION SHIFTS AND LOSES ALL FORMS OF ENGINE BRAKING CAUSING THE TRUCK TO SPEED UP AND OVERSHOOTS THE STOPSIGN.

Service Brakes
Filed Jan 7, 201977,000 milesCA

POOR BRAKE PERFORMANCE. THE BRAKE PEDAL GETS STIFF AT A LOW SPEED AND CAUSES THE TRUCK TO NOT BRAKE COMPLETELY

Service Brakes
Filed Dec 11, 201870,135 milesAR

FAILURE OF THE BELT DRIVEN VACUUM PUMP WHILE DRIVING CAUSING VERY HARD BRAKING AND ALMOST CAUSED AN ACCIDENT. VACUUM PRESSURE DROPPED OFF AND CAUSED THE PEDAL TO BECOME FIRM. LUCKILY AFTER IT WAS INSPECTED FOR REPAIR THERE WASN'T OIL CONTAMINATION IN THE VACUUM LINE OR BRAKE BOOSTER SO THOSE DID NOT HAVE TO BE REPLACED.

Service Brakes
Filed Nov 24, 201846,000 milesMA

POWER BRAKE VACUUM PUMP ISSUE. LOST BRAKES WHILE DRIVING IN STOP AND GO CITY TRAFFIC. HAD TO HAVE TRUCK TOWED, WAS UNSAFE TO DRIVE DUE TO NO BRAKES.

Electrical System
Filed Oct 18, 201847,800 milesMD

INTERIOR DASH LIGHTS GOES OUT AND A FEW MINUTES LATER THE ENGINE CUTS OFF WHILE I'M TRYING TO PARK. EACH TIME WHILE I WAS BACKING INTO MY PARKING SPACE. AFTER SITTING FOR ABOUT 30 SECONDS THE LIGHTS DASH BOARD LIGHTS COME BACK ON, THEN I RESTART THE TRUCK. SOMETIMES WHILE DRIVING THE DASH BOARD LIGHT BLINK OF AND ON.

Electrical System
Filed Aug 4, 201822,567 milesOH

VEHICLE STARTED SHOWING "SERVICE LANE DEPARTURE SYSTEM, SERVICE PARK ASSIST, SERVICE TRAILER BRAKE SYSTEM" ALARMS WHILE DRIVING. UPON TAKING IT TO THE DEALER FOR SERVICE IT WAS FOUND TO HAVE BROKEN WIRING FOR HAPTIC MOTOR FOR DRIVERS SEAT. NOT ONLY DID THIS CAUSE A POSSIBLE SAFETY ISSUE WITH THE LANE DEPARTURE SYSTEM AND TRAILER BRAKE SYSTEM NOT WORKING CORRECTLY, BUT IT ALSO CAUSED A POSSIBLE FIRE CONCERN DUE TO BROKEN WIRING.

Power Train
Filed May 25, 201855,000 milesTX

STARTING THE VEHICLE I'M PUTTING THE TRUCK IN REVERSE, THE TRUCK LUNGES BACKWARDS. ALSO A VIOLENT JERK OF THE VEHICLE HAPPENS. THIS HAPPENS A MAJORITY OF THE TIME. PUTTING THE VEHICLE INTO GEAR TO DRIVE I HAVE A VIOLENT JERK AND A LOUD NOISE. THE TRUCK DOES NOT LUNGE FORWARD WHEN PLACING THE TRUCK INTO DRIVE. THIS HAPPENS A COUPLE OF TIMES A DAY. THIS IS NOT AN ISOLATED INCIDENT.

Service Brakes
Filed Feb 4, 201856,000 milesTX

HARD BRAKE PEDAL. AT LOW SPEED THE BRAKE PEDAL GETS REALLY HARD AND MAKES IT HARD TO STOP THE TRUCK. PEDAL HAS TO GET PUSHED REALLY HARD TO BARELY STOP FROM HITTING OTHER VEHICLES. ONGOING ISSUE.

Steering
Filed Dec 20, 201739,900 milesTX

TL* THE CONTACT OWNS A 2015 GMC SIERRA DENALI. WHILE DRIVING APPROXIMATELY 60 MPH, THE STEERING LOST POWER AND THE POWER STEERING WARNING INDICATOR ILLUMINATED. THE VEHICLE WAS TOWED TO THE DEALER (SEWELL BUICK GMC OF DALLAS IN DALLAS, TX, PHONE NUMBER: 214-350-8000) WHERE A DIAGNOSTIC TEST WAS PERFORMED. THE CONTACT WAS NOT GIVEN THE RESULTS OF THE TEST. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE AND OFFERED TO PAY A PERCENTAGE OF THE REPAIR COSTS. THE FAILURE MILEAGE WAS 39,900. *BF UPDATED 8/28/18*JB

Air Bags
Filed Oct 16, 2017AK

2015 GMC SIERRA. CONSUMER WRITES IN REGARDS TO SENSING AND DIAGNOSTIC MODULE SAFETY RECALL. *LD THE CONSUMER REQUESTED TO BE ADVISED OF THE OPTIONS OF HAVING A RECALL COMPLETED ON AN ISLAND. UPDATED 10/16/2017*JS

Electrical SystemCrash
Filed Oct 13, 201715,000 milesMA

TL* THE CONTACT OWNS A 2015 GMC SIERRA DENALI. THE CONTACT STATED THAT THE VEHICLE EXHIBITED NUMEROUS ELECTRICAL FAILURES. THE FAILURE CAUSED THE STEERING WHEEL TO LOCK, THE BRAKE SYSTEM NOT TO ENGAGE, AND THE INSTRUMENT PANEL AND ALL OTHER ELECTRICAL SYSTEMS IN THE VEHICLE NOT TO OPERATE NORMALLY. THE VEHICLE WAS TAKEN TO MARTY'S BUICK GMC (5 COLLECTION WAY, KINGSTON MA, 02364, 781-585-7570) SEVERAL TIMES FOR THE FAILURE. THE CONTACT STATED THAT THE DEALER REPLACED WIRES, BUT THE FAILURE WAS NOT CORRECTED. THE CONTACT DID NOT KNOW THE NAME OF THE WIRES THAT WERE REPLACED. THE CONTACT ALSO STATED THAT THE ELECTRICAL FAILURE ALSO CAUSED A CRASH ON THE ROAD MEDIAN BECAUSE THE STEERING WHEEL LOCKED. THERE WERE NO INJURIES AND A POLICE REPORT WAS NOT FILED. THE VEHICLE WAS TAKEN BACK TO THE DEALER FOR FURTHER INSPECTION. THE MANUFACTURER WAS NOTIFIED. THE VIN WAS NOT AVAILABLE. THE FAILURE MILEAGE WAS 15,000.

Engine
Filed Jul 3, 201746,000 milesTX

MY GMC 2015 DIESEL DURIMAX TRUCK HAD THE ENGINE LIGHT TURN ON AND SAID EMISSION NEEDS SERVICED. IT PROCEEDED TO CUT MY TRAVELING SPEED FROM 75 MPH TO 65 MPH TO 55 MPH. I MADE IT TO DENVER COLORADO BARELY WITHOUT THE TRUCK FALLING TO 4 MPH. I WENT YESTERDAY TO HAVE IT SERVICED. THEY SAID THAT THEY FIXED IT STILL UNDER POWERTRAIN WARRANTY. I DROVE AWAY TO GO BACK TO TEXAS 700 MILES OF HIGHWAY HOME. I DROVE AND THE EXACT SAME PROBLEM HAPPENED AGAIN. I'M WAS ON A HIGHWAY AT THIS POINT WITH HEAVY HIGHSPEED TRAFFIC IN THE MIDDLE OF NOWHERE WHERE THE SPEED LIMIT IS 75 MPH. MY TRUCK SPEED WAS REDUCED BY THE EMISSION SYSTEM AGAIN FROM 75 MPH TO 65 MPH TO 55 MPH. I WAS ALMOST HIT BY A BIG RIG TRUCK WITH MY WIFE IN THE CAR. SOMETIME LATER WERE ALMOST SIDE SWIPED TWICE, AND THEN IT STARTED RAINING AND THE SUN STARTED TO SET, AND MATTERS WENT FROM DANGEROUS TO NEAR DEADLY. WE TRIED TO TURN THE TRUCK AROUND TO GET BACK TO DENVER AND ALMOST WERE HIT AGAIN BECAUSE WITH THE GMC SPEED REDUCTION I COULD NOT ACCELERATE AWAY FROM THE HIGH SPEED CARS COMING AT US. GMC SHUTDOWNS THE CAR SPEED PURPOSELY TO AVOID SOME TINY AMOUNT OF NOX, AND PUT PEOPLE AT RISK OF BEING KILLED ON A HIGHWAY IN RAINY NIGHTIME WEATHER. WE FINALLY MADE IT BACK TO DENVER JUST 19 MILES BEFORE THE TRUCK SPEED WOULD HAVE BEEN REDUCED TO 4 MPH. WE WOULD HAVE TO BEEN ON THAT 75 MPH HIGHWAY RIDING IN THE RIGHT SIDE OF THE SLOW LANE AT 4 MPH !!!!! AT NIGHT IN THE RAIN WITH HIGH SPEED 18 WHEELERS GOING BY AT 75 TO 85 MPH. THE GOVE

20 of 22 complaints, reproduced as filed.

Across model years

Worst on record: 2016
YearComplaintsRecallsFiresDeathsAssessment
202011000Routine
201926000Routine
201817000Routine
201714000Routine
201630000Routine
2015 — this page22000Routine
201414000Routine
20138000Routine
201210000Routine
201128000Routine
201010000Routine
20097000Routine
200818000Routine
20071000Routine
20065100Routine
20054200Routine
200411100Routine
200213100Routine

Compare every Sierra Denali year →

Reading this record

No unusual pattern of severe incidents in the complaint record.

Complaint counts track how many cars were sold and how long they have been on the road as much as they track quality. A common model from 2013 has had a decade to accumulate reports; a rare one from last year has not. The signal worth weighing is in the severity columns, in whether the same component keeps appearing, and in whether the manufacturer eventually opened a recall for it.

Most recent recall on file: none. Source: NHTSA Office of Defects Investigation.