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

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

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

NHTSA ODI 11619840

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

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

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

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

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 ODI 11191265

VEHICLE IS ONLY 3 WEEKS OLD. A FAULTY ENGINE WIRE HARNESS CAUSED THE VEHICLE TO CEASE OPERATING IN TRAFFIC AND PUT MY FAMILY IN A POTENTIALLY LIFE THREATENING SITUATION. MERCEDES DID NOT REPLACE BUT ONLY "REPAIRED" THE WIRE, WHICH WE WERE TOLD WAS NOT ASSEMBLED CORRECTLY AND WAS PINCHED IN A BRACKET AND SUBSEQUENTLY CHAFED, WHICH CAN POTENTIALLY STILL CAUSE A LIFE THREATENING ENGINE MALFUNCTION DURING NORMAL OPERATION. MERCEDES IS NOT WILLING TO REPLACE THE ENGINE HARNESS WIRE, NOR REPLACE THE VEHICLE. I FEAR FOR THE SAFETY OF MY FAMILY.

NHTSA ODI 10934831