What 22 owners told NHTSA about the 2018 Mercedes-benz GLS

January 2023 - Airbag suspension failed. Replaced by Mercedes dealership. December 2024 - Airbag suspension failed. Replaced by Mercedes dealership. April 2024: First brake failure. The brakes stopped while driving. Repaired. April 2025: Second brake failure. Brakes failed again. Repaired. The mechanic stated the line was too close to the wheelbase, resulting in a pinpoint-sized hole. No warning lights. July 2025: Engine failure - the vehicle experienced a complete shutdown while driving with no warning lights. Vehicle in shop for 6-8 weeks for engine replacement by certified Mercedes mechanic. Post-engine replacement (July - Nov 2025) - Severe oil leaks at left cylinder head, small leaks at right cylinder head. Coolant warnings and overheating despite adequate coolant. Radiator and vent line issues. Active Brake Assist Limited warning appeared. Late November - Vehicle emitted smoke and experienced a small engine fire, observed under hood after stopping. Mercedes dealership deemed car unsafe to drive. During engine replacement wood pieces were found where destroyed motor mounts should have been. Multiple issues with no notice or warning lights.

NHTSA ODI 11703281

The contact owned a 2018 Mercedes Benz GLS450. The contact stated that after turning the ignition switch off, the driver suddenly discovered flames were coming from the engine compartment. The fire department was called to the scene and extinguished the flames. During the incident, the vehicle was destroyed and later towed away. A fire report was taken at the scene. The cause of the failure was not determined. The manufacturer and local dealer were notified of the failure. The VIN was not available. The failure mileage was 15,000.

NHTSA ODI 11436804