2017 Mercedes-Benz GLS450 Owner Complaints

Car did not brake when going about 5-7mph and crashed into another car.

NHTSA ID

11713114

Incident

Dec 19, 2025

The contact owns a 2017 Mercedes-Benz GLS450. The contact heard an abnormal humming sound when the vehicle was started, and the humming sound grew louder over time. The contact believed that the humming sound was coming from the driver's side headlamp. The contact stated that the headlamp was equipped with a small internal fan to dissipate heat. Additionally, other electrical failures were occurring, and the vehicle was taken to a local dealer. The dealer diagnosed the vehicle and determined that the blower motor had failed and needed to be replaced. The vehicle was repaired; however, the humming sound returned. The vehicle was taken to the dealer on two more occasions, and the dealer replaced the timing belt and the alternator, however the failure reoccurred. Recently, while touching the door handle, the contact heard a humming sound that was very loud. The vehicle was taken back to the dealer, and it was determined that the driver's side headlamp assembly needed to be replaced. The vehicle was not repaired. The contact researched online and related the failure to NHTSA Campaign Number: 20V626000 (Electrical System, Steering, Exterior Lighting, Visibility); however, the VIN was not included. The manufacturer was contacted and confirmed that the VIN was not included in the recall. The failure mileage was 135,500.

NHTSA ID

11710906

Incident

Aug 14, 2025

Mileage

135,500 mi

My 2017 Mercedes-Benz GLS 450 is experiencing serious and unpredictable transmission behavior related to the valve body and shifting mechanism. The transmission sometimes fails to engage Park, shifts on its own without driver input or attempts to engage Reverse unexpectedly. On multiple occasions the vehicle has moved or rolled after being placed in Park and once it appeared to shift itself toward Reverse. This behavior is a clear safety risk as the vehicle can suddenly lose control or move unexpectedly. It happens intermittently, without any dashboard warnings and often resets temporarily after restarting the car. According to multiple owners posting on Mercedes-Benz forums (including MBWorld, BenzWorld, and Mercedes-Benz Owners Club discussions), this issue is common among GLS and other Mercedes models using the same transmission. Many owners report identical symptoms: transmission slipping into Neutral or Reverse, failure to engage Park or erratic shifting caused by a malfunctioning valve body, defective solenoids or Transmission Control Module (TCM) faults. Some have shared diagnostic codes such as P073E and P07B7 that point to reverse and park circuit errors. Mercedes technicians and independent repair specialists who have posted on these forums frequently identify the valve body assembly as the source of the issue. Common explanations include internal hydraulic pressure faults, electrical connector leaks or sensor failures inside the valve body. Owners have been quoted thousands of dollars for valve body replacements as i was billed $2300+. This problem is not isolated to my vehicle and appears to be a recurring design or manufacturing defect that affects multiple model years and platforms sharing this transmission. Because the vehicle can unexpectedly shift or fail to hold Park, it creates an immediate safety concern for both drivers and bystanders. I have video of this dangerous issue

NHTSA ID

11695525

Incident

Feb 15, 2025

On July 23, 2025, I drove my Mercedes-Benz GLS 450 to a medical appointment. After arriving, I parked near the valet station, turned off the car, and went inside to check in at LabCorp. Within two minutes, witnesses reported black smoke from the hood — followed by a violent explosion that shook the office building and triggered a multi-unit response from local fire and police departments. When I came downstairs, my vehicle was engulfed in flames. The front end was completely destroyed. Mercedes-Benz USA sent an investigator on September 8, 2025 to examine the wreck. Despite numerous follow-ups, I have received no written report, no findings, and no communication from Mercedes-Benz since that inspection detailing any relevant information. Safety Context: In March 2024, Mercedes-Benz issued Recall #24V-207, affecting 2019–2023 GLE and GLS models, citing a defective 48-volt ground connection that could cause a fire. My incident occurred in a GLS 450 model and appears consistent with this recall defect. If confirmed, this could indicate that the recall did not capture all affected VINs or that repairs were not properly executed. This incident was minutes from being fatal — and could easily have occurred on the highway or in my garage or with my 4 children inside. The lack of corporate response for over two months raises serious concerns about consumer safety, recall effectiveness, and corporate transparency.

NHTSA ID

11693202

Incident

Jul 23, 2025

Vehicle Information: Make: Mercedes-Benz Model: GLS 450 Year: 2017 Component: Visibility/Sunroof/Panoramic Glass Roof VIN: [XXX] Incident Date: [XXX] Complaint Summary: I am filing this complaint regarding a serious and dangerous safety defect in my 2017 Mercedes-Benz GLS 450. Without warning and while driving, the panoramic glass sunroof suddenly shattered and exploded, sending glass shards and debris into the vehicle cabin. My two young children were seated inside at the time, and glass pieces fell directly onto them, causing extreme distress and posing a severe risk of injury. There was no impact or external cause—the sunroof shattered spontaneously. The incident left glass scattered throughout the interior of the vehicle, including on the seats, floor, and children’s car seats. Fortunately, my children were not severely injured, but the potential for serious harm was extremely high. After researching this issue, I discovered that this is not an isolated incident. Numerous complaints have been filed with the NHTSA and other authorities regarding spontaneous sunroof shattering in Mercedes-Benz vehicles, including this model. Additionally, I understand that a federal judge recently approved a class action lawsuit addressing this exact issue, further highlighting the severity and prevalence of the defect. This is a significant safety hazard that must be addressed. I urge the NHTSA to investigate this issue further and take appropriate regulatory or enforcement action to ensure the safety of all vehicle occupants. Additional Details: No recent repairs or modifications to the sunroof or roof area. Vehicle was in motion on a clear day with no overpasses or external objects that could have impacted the roof. The noise was loud, like an explosion, followed by immediate glass breakage. I have retained photos of the damage and can provide them if needed. Requested Action: Please investigate this matter urgently. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11666914

Incident

Jun 7, 2025

Vehicle check engine light came on early August 2024. Vehicle was brought in for service and checked for codes. B1F4500 Battery has excessive resistance B21059A The operating conditions of component have not been satisfied. Battery was replaced and rechecked. Po4427A Evap leak detected P04F000 Charcoal canister has a malfunction Smoke tested EVAP system to see if there was any leaks and tested the valves to make sure EVAP system was working correctly. Charcoal canister not actuating correctly so was replaced and checked. Gas cap also replaced Several days later Check engine light returns. Code continues to say "Small leak in the EVAP system." Every time the code is cleared it returns and Check Engine light returns. This has been going on for 7 months. Car cannot obtain the required SMOG inspection in California that is required for an annual registration of the vehicle. I believe the vehicle may need to be part of the Emission Service Campaign 2024030005 which has effected 16 other vehicles. Mercedes tells me that an update to the Engine Control Software will not be allowed because my vehicle is not one of the 16 vehicles that are currently effected by this issue. The issue is for the same make, model and year as my vehicle.

NHTSA ID

11646348

Incident

Aug 8, 2024

This is the 2nd time within a year my airmatic suspension system has went out while driving and I have lost control of driving my vehicle. I have paid 3900 to have the problem repaired it has not been a year and the same issue has happened. Faulty dangerous suspension system airbag suspension is dangerous and faulty.

NHTSA ID

11628461

Incident

Nov 29, 2024

Fire started in the Engine and consumed the entire vehicle in less than 5 minutes

NHTSA ID

11619840

Incident

May 3, 2024

My suspension failed would not send any air pressure to lift my vehicle while driving my car ride was very bumpy and I loss contol.

NHTSA ID

11577198

Incident

Mar 13, 2024

The contact owns a 2017 Mercedes-Benz GLS450. The contact stated that upon starting the vehicle after driving in a rainstorm, the power steering malfunction message was displayed. While driving approximately 70 MPH, the power steering became inoperable. The vehicle was taken to the local dealer where it was diagnosed and determined that the failure was due to the electronic power steering rack. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 17V241000 (Steering). The manufacturer was contacted and notified of the failure and the contact was referred to NHTSA Hotline for assistance. The failure mileage was approximately 29,210.

NHTSA ID

11529734

Incident

Jun 16, 2023

Mileage

29,210 mi

Car destroyed by fire on March 19, 2023 while at a quick stop near Chickasaw, OK. Car was last serviced by Mercedes-Benz of Oklahoma City in December 2022. No personal injuries just a total loss of the vehicle. Cause of the fire at present is unknown. Pictures are available.

NHTSA ID

11513006

Incident

Mar 19, 2023

I purchased this Vehical Al from auto of Texas in carralton tx I don’t have seatbelt on the second row so I am unable to buckle my children in I have contacted dealership three time for two weeks and they have not fixed the problem I have only have vehicle for 22 day didn’t not notice the where not seatbelts until after I purchased it my niece was thrown from the seat due to no seatbelt

NHTSA ID

11468747

Incident

Jun 4, 2022

Over time, the low beam lights have faded which make it very difficult to see at night.

NHTSA ID

11455473

Incident

Jan 1, 2021

Our car, Mercedes GLS 450, caught on fire after pulled into the garage from a short drive on local streets, which resulted a total loss on our house. After pulling into the garage, the home link didn't work when tried to use it to close the garage door. Upon coming out of the car, smoke came out from under the hood and soon after it became flame. We attempted to extinguish the fire with a fire extinguisher as it appeared with hood still closed and fire immediately came back. By the time the firefighters came, there was a full fledged fire. The fire has burned the car beyond recognition and the garage was burned too. The fire and smoke has caused a total loss on our house. There were NO warning lights or warning messages at all before smoke or fire started. Investigators hired by Mercedes Benz inspected the burnt car and concluded the fire was due to a missing oil cap. While questionable the oil cap was the source of the fire, it seems the GLS 450 didn't have a sensor for missing oil cap to trigger a warning light or warning message, which is what some less sophisticated cars have because modern engines have positive crankcase ventilation. If indeed missing oil cap could cause full fledged fire, shouldn't Mercedes put a sensor to warn the customers? There is a recall, see link below, on almost all Mercedes model cars in Jan. 2022 for the reason that the car could catch on fire. Our GLS was built just two months before the starting timeline on the recall and it caught on fire and burned our house. Could it be coincidence or did our car catch on fire due to the exact same reason on this recall? (https://www.forbes.com/sites/zacharysmith/2022/01/04/800000-mercedes-benz-owners-warned-their-cars-could-catch-fire/)

NHTSA ID

11452172

Incident

May 20, 2021

THE OTHER DAY AFTER A STORM MY SUV WAS PARKED AT THE STREET AND WHEN I OPENED THE LIFT GATE WATER START TO COMING OUT FROM THE INTERIOR I ALSO COULD SEE WATER IN THE INTERIOR LIGTHS .

NHTSA ID

11384062

Incident

Dec 5, 2020

CENTER CONSOLE IS NOT SAFELY INSTALLED AND MOVES WHILE DRIVING. EVIDENCE IS THAT MERCEDES-BENS HAS NOW TWICE UPDATED THE PART FOR REPLACEMENT, BUT DOES ACTIVELY OFFER THAT FOR EXISTING OWNERS: ORIGINAL PART:166-680-16-52 1ST REVISION PART:166-680-38-03 2ND REVISION PART: 166-680-86-04

NHTSA ID

11376132

Incident

Nov 6, 2018

Mileage

20,000 mi

I DROVE UP AND DOWN THE WESTERN UNITED STATES ON HIGHWAYS AND CITY STREETS. I DROVE 16 HOURS A DAY FOR ABOUT 1 WEEK. I RECEIVED A CHECK ENGINE LIGHT WITH A WARNING THAT THERE WAS A SMALL EVAP LEAK. AFTER BEING SERVICED THIS WARNING DID NOT APPEAR AGAIN. I BELIEVE THE THRESHOLDS WERE UPDATED TO IGNORE SMALL EVAP LEAKS. AROUND OCTOBER 28, 2019, I NOTICED THE FLOOR BOARD OF MY VEHICLE OVERHEATING. I ALSO DETECTED MORE EXHAUST FUMES ENTERING THE CABIN. I BELIEVE THE CATALYTIC CONVERTERS ARE LESS EFFECTIVE AND A BLOCKAGE IS CAUSING MORE EXHAUST TO LEAK FROM THE EMISSIONS SYSTEM. HOWEVER NO CHECK ENGINE LIGHT WARNING SO THE MANUFACTURER WILL NOT REPAIR UNDER WARRANTY. I WAS INITIALLY GETTING HEADACHES AND EXPERIENCING PAIN IN MY SPINAL CORD. NOW I AM EXPERIENCING CHEST PAINS WHILE DRIVING.

NHTSA ID

11324007

Incident

Oct 28, 2019

Mileage

56,000 mi

HEADLIGHTS ARE NOT SAFE. FOWARD VISIBILITY IS VERY POOR. THIS VEHICLE SHOULD NOT BE DRIVEN AT NIGHT ESPECIALLY IN POOR WEATHER CONDITIONS.

NHTSA ID

11298065

Incident

Jan 2, 2020

Mileage

41,097 mi

2017 MERCEDES BENZ GLS 450 4MATIC PURCHASED SEPTEMBER 2016. RETURNED VEHICLE TO DEALERSHIP 6 (SIX) TIMES FOR FOUL SMELL COMING FROM AIR CONDITIONING UNIT. FOUL, MOLDY SMELL STILL REMAINS. DEALER HAS CHANGED MULTIPLE PARTS, CLEANED THE A SYSTEM AND REPLACED DUST AND FINE PARTICLE FILTER EACH TIME. THE SMELL ALWAYS COMES BACK. DEVELOPED A RECURRING COUGH BECAUSE OF SMELL. AFTER CALLING A LAWYER I FOUND OUT THAT THERE IS A CLASS ACTION LAWSUIT REGARDING MULTIPLE MERCEDES BENZ MODELS INCLUDING THE 2017 GLS450.

NHTSA ID

11230308

Incident

Jul 24, 2017

Mileage

12,314 mi

2017 MERCEDES BENZ GLS450. CONSUMER WRITES IN REGARDS TO MALFUNCTIONING BRAKES. *LD THE CONSUMER STATED THE VEHICLE EXPERIENCED PREMATURE WEAR OF THE BRAKES. THE VEHICLE LEAKED FUEL. THE INTERIOR DOOR TRIM WAS NOT SECURE. *JS

NHTSA ID

11196350

Incident

Mar 27, 2017

TL* THE CONTACT OWNED A 2017 MERCEDES-BENZ GLS450. AFTER THE VEHICLE WAS PARKED FOR APPROXIMATELY 30 SECONDS, IT CAUGHT FIRE. PRIOR TO THE FAILURE, THE CONTACT NOTICED THAT THE CUP HOLDER AND ARMREST CONSOLE WERE HOT. THE CONTACT NOTICED AN ODOR OF BURNING RUBBER IN THE VEHICLE. THE FIRE DEPARTMENT EXTINGUISHED THE FIRE. A FIRE REPORT WAS FILED. THE VEHICLE WAS DESTROYED, TOWED, AND QUARANTINED AT THE INSURANCE COMPANY'S IMPOUND LOT. VALLEY IMPORTS (LOCATED AT 402 40TH ST S, FARGO, ND 58103, (888) 929-9843) AND THE MANUFACTURER WERE NOTIFIED OF THE FAILURE. THE CAUSE OF THE FIRE WAS NOT DETERMINED. THE APPROXIMATE FAILURE MILEAGE WAS 40,000. *TT THE CONSUMER STATED THE FIRE DEPT DETERMINED IT TO BE A LEAKY HOT LIQUID. *TR

NHTSA ID

11191265

Incident

Mar 3, 2019

Mileage

40,000 mi

AFTER OWNING THE VEHICLE FOR MORE THAN 2 YEARS, THE REAR TAILGATE OPENED BY ITSELF 3 TIMES IN 8 DAYS. THE FIRST TIME, THE VEHICLE WAS PARKED IN OUR HOME GARAGE. THE SECOND TIME, WE WERE TRAVELING ON A CITIY STREET WHEN THE TAILGATE JUST POPPED OPEN ON ITS OWN. THE THIRD TIME, WHEN EXITING A PARKING GARAGE WITH A LOW ROOF, IT OPENED BY ITSELF, STRIKING THE LOW OVERHANG IN THE GARAGE. THIS TIME, THE GLASS WAS BROKEN AND THE BODY DAMAGED. THE FIRST INCIDENT OCCURRED WHEN THE VEHICLE WAS PARKED. THE SECOND INCIDENT, THE VEHICLE WAS MOVING AT 35 MPH. THE THIRD INCIDENT, THE VEHICLE WAS MOVING AT ABOUT 5 MPH.

NHTSA ID

11183628

Incident

Feb 1, 2019

Mileage

5,900 mi

I'VE GONE THROUGH 3 SETS OF TIRES THAT THE REAR 2 TIRES ARE ALWAYS BALD FIRST. I'VE HAD THE ORIGINALS BALD, THEN THE SNOW PIRELLI AND NOW THE MICHELIN. IS THERE A KNOWN ISSUE OR RECALL WITH THE 2017 GLS 450?

NHTSA ID

11181020

Incident

Feb 19, 2019

ON FRIDAY 11/30 MY 2017 MERCEDES GL450 SUFFERED A CATASTROPHIC ELECTRONIC MALFUNCTION THAT LED TO A) NO ABILITY TO GET CAR OUT OF DRIVE (E.G. WOULDN'T PARK, REVERSE, COULDN'T TAKE MY FOOT OFF THE BRAKE), B) NO ABILITY TO TURN CAR OFF, C) POWER STEERING WENT OUT, D) AIRBAGS FLAGGED AS INACTIVE, E) MOST ALL MY DASHBOARD WARNING LIGHTS WENT ON INCLUDING ONE THAT SAID "MALFUNCTION", F) MY DASHBOARD GAUGES FAILED (E.G. NO WORKING ODOMETER), G) THE REAR HATCH COULDN'T OPEN. THIS HAPPENED WHILE DRIVING MY FAMILY -- INCLUDING 2 YOUNG CHILDREN -- THROUGH THE DESERT, PUTTING US AT VERY GREAT RISK. MY CAR IS BEING SERVICED AT MB OF VALENCIA (THE CLOSEST ONE I COULD DRIVE TO). I'M BEING TOLD BY THEM THAT A MINOR, LOW-SPEED AND LOW-IMPACT DENT IN MY REAR BUMPER CAUSED A MISALIGNMENT IN MY EXHAUST, WHICH BLEW HOT AIR INTO THE BUMPER AND CAUSED THE BLIND SPOT ASSIST TO MELT. THIS SEEMS LIKE A MAJOR DESIGN FLAW -- THAT A SMALL MISALIGNMENT COULD CAUSE A SEVERE AND LIFE-THREATENING CASCADING SYSTEM MALFUNCTION IF LEFT UNTREATED, AND THAT I HAD NO WARNING OF ANY KIND THAT WHAT APPEARED TO BE A MINOR DENT WAS A MAJOR ISSUE. I WANT TO KNOW IF OTHERS HAVE HAD THIS HAPPEN, AND IF THIS WARRANTS INITIATING A RECALL INVESTIGATION. MY INSURANCE COMPANY IS TAKING PHOTOS AND WRITING UP FINDINGS. I'LL PROVIDE THEM ON REQUEST.

NHTSA ID

11156582

Incident

Nov 30, 2018

ROAD VISIBILITY IS POOR WITH LOW BEAM LIGHTING ON NORMAL WEATHER CONDITION DURING NIGHTTIME. IT INCREASES DANGER WHEN IT RAINS AND/OR FOGGY WEATHER DURING NIGHTTIME.VISITED DEALERSHIP AND BROUGHT UP ISSUES, BUT MBENZ CAN'T FIX IT SINCE IT PASSES ITS STANDARD. NHTSA, PLEASE DO MORE RESEARCH ON THIS ISSUE PROACTIVELY FOR SAFETY. I BELIEVE ITS A SERIOUS PROBLEM. THIS BIG LUXURY TRUCK MOSTLY USE BY FAMILIES. KEEP THEM SAFE!

NHTSA ID

11103896

Incident

Jun 25, 2018