Home · 2017 Mercedes-benz GLS · Complaints

What 41 owners told NHTSA about the 2017 Mercedes-benz GLS

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (41)Crash / fire / injury (8)Electrical system (8)Engine (8)Fuel system (6)Lights (6)Steering (4)Seats (3)Transmission & drivetrain (3)Body & structure (2)Suspension (2)Brakes (1)

Newest first · 41 complaints · page 1 of 2

Jul 2, 2026Seats1 injury

I was driving around and my [XXX] daughter was complaining that the seat was getting super hot . I told her to stop playing with the seat warmer she then replied she was not . I kept driving and then she again told me it was burning her so i pulled over and saw that her leg was super red and i saw the seat was pretty melted . I called mercedes care center and they adviced me to take it to my local mercedes dealer . They are quoting me almost 4000 dollars and also replied with this message, “Good afternoon [XXX] we heard back from Mercedes Benz CAC and they have advised us they are not offering any assistance towards the seat repair. Please contact me when you have a moment. Thank you.” INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11748048

Jan 24, 2026Driver assistanceCrash

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

NHTSA ODI 11713114

Jan 14, 2026Electrical systemLightsVisibility & wipers

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 ODI 11710906

Oct 24, 2025Transmission & drivetrain

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 ODI 11695525

Oct 13, 2025EngineFire

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 ODI 11693202

Aug 5, 2025Fuel system

Feel unsafe fuel rails and more where recalled in April 2022 Not all gls550 were recalled at the time due to no reason Drive to Florida with my wife and kids and car gave up on the side of a bridge hwy over the ocean We were stuck car smelt like gas and wouldn’t turn on we had nowhere to get out on a 25ft bridge with no ac no emergency lanes with 5 kids all under age of 6

NHTSA ODI 11678641

Jun 14, 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 ODI 11666914

Mar 4, 2025Fuel system

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 ODI 11646348

Dec 3, 2024Suspension

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 ODI 11628461

Oct 15, 2024Electrical systemEngineFuel systemFire

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

NHTSA ODI 11619840

Mar 13, 2024Suspension

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 ODI 11577198

Jun 30, 2023Steering

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 ODI 11529734

Mar 21, 2023Electrical systemEngineFuel systemFire

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 ODI 11513006

Jun 11, 2022Seat belts

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 ODI 11468747

Mar 7, 2022Lights

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

NHTSA ODI 11455473

Feb 16, 2022Electrical systemEngineFuel systemFire

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 ODI 11452172

Dec 18, 2021Engine

We had our Mercedes GLS550 2017 with 59,295 overheat and call for immediate shut down on the Massachusetts Turnpike with my wife and child in the car. It was quite a dangerous situation because the failure caused by hose assembly 166-830-15-00 clamp (as described by the dealer as the reason for the loss of fluid and hose failure) caused almost an immediate overheating. The service advisor stated that it is "a quite common failure". I was quite suspicious, because just 11 days prior and 138 miles prior they had performed an Oil Change (Service B9), and thought their mechanic must have damaged the hose fitting they claimed broke. When I looked at the schematic, the fitting is quite close to the Oil Filter Cap, so I assumed that the mechanic accidentally knocked the plastic clamp and broke it. However, they said this was a "normal failure" on these cars. I am a data scientist and have requested failure rates for similar autos in the data cohorts of 50,000, to 60,000 miles and 4 to 5 years old. It woudl be also nice to see if there was data available that included Post B( service visits for the same failures. I was surprised they tracked this data since I was told it was a common failure of this part. Looking at the design of where the host runs, it is certainly exposed to a mechanics tools removing the Oil Filter wrench. If this is common, I would like to help other families with young children being stranded by the side of a busy highway. In this case, I told my wife to drive to the closest safe point even though the engine warning system said to stop immediately. The engine seems to survive fine. I dont know if you record other data on this type of hose assembly failure, but a redesign with non-plastic clamp might be more durable and more appropriate.

NHTSA ODI 11444249

Mar 12, 2021

MY WIFE AND I WERE DRIVING FROM ARIZONA TO COLORADO. WE WERE TRAVELING AT ABOUT 85 MILES/ HR PASSING ALBUQUERQUE. ALL OF A SUDDEN WE FELT AND HEARD AN EXPLOSION. MY WIFE AND I BOTH DUCKED AND FORTUNATELY I KEPT MY HANDS ON THE WHEEL. WE LOOKED UP AND THE SUNROOF HAD SHATTERED AND BLOWN OUT. THE ONLY THING THAT SAVED US FROM BEING SHOWERED WITH GLASS WAS THE SHADE OF THE SUNROOF WAS CLOSED BECAUSE THE SUNROOF WAS CLOSED AT THE TIME. WE HAD T DRIVE THE REMAINING 400 MILES WITH THE BROKEN SUNROOF. WHEN WE GOT BACK HOME , WE CONTACTED MERCEDES AND ASKED THEM ABOUT THE SUNROOF. THEY BASICALLY DID NOT ACCEPT ANY RESPONSIBILITY FOR ANYTHING EVEN AFTER WE TOLD THEM THAT AFTER GOOGLING ( MERCEDES EXPLODING SUNROOF) A TON OF ITEMS CAME UP INCLUDING SEVERAL LAWSUITS. MERCEDES DOES NOT SEEM TO WANT TO ACCEPT ANY RESPONSIBILITY FOR THE SUNROOF. MY WIFE AND I COULD HAVE BEEN KILLED. WE WERE LUCKY THAT THERE WAS NO CAR AROUND US AND THE FACT THAT I KEPT MY HANDS ON THE STEERING WHEEL. I DO NOT WANT THIS TO HAPPEN TO ANY ONE ELSE BECAUSE THEY MIGHT NOT BE AS FORTUNATE AS US.

NHTSA ODI 11402698

Dec 18, 2020Body & structure

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 ODI 11384062

Nov 24, 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 ODI 11376132

Jul 21, 2020Transmission & drivetrain

REAR AXLE LOCK UP BRIEFLY MADE A SOUND LIKE SOMEONE REAR ENDED THE CAR AND SNAP THE LEFT SIDE REAR CV AXLE. VEHICLE IS AWD AND DOES NOT MOVE ON ITS OWN POWER.. SHOP TOW SUV AND ON THE AIR FOUND THE AXLE INNER JOINT JUST SPINS BUT CAR DOES NOT MOVE, THEY PULLED THE AXLE AND THE IS METAL BURNT INTO THE AXLE SHAFT SEEMS REAR DIFF LOCK UP, OIL WAS CLEAN ON THE DIFFERENTIAL.

NHTSA ODI 11340655

May 10, 2020Engine1 injury

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 ODI 11324007

Jan 9, 2020Lights

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

NHTSA ODI 11298065

Jul 8, 2019

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 ODI 11230308

Apr 18, 2019Fuel systemBody & structureBrakes

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 ODI 11196350

Older →

Working with the data? Download all 41 complaints as CSV · fetched from NHTSA July 20, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2017 Mercedes-benz GLS verdict →