— Mercedes-Benz transmission problems have caused a recall of 105,000 GLE 450 and GLS 450 vehicles because the transmissions may not completely downshift, causing the engines to stall.
The recalled 2020-2023 GLE 450 and GLS 450 vehicles need updates to the transmission control unit software.
"If a downshift of the transmission from 7th to 6th gear is not fully completed during a simultaneous slight braking maneuver of the vehicle, and additional conditions exist (e.g. aborted shift operation, low transmission oil temperature, simultaneous recuperation by the 48V starter-alternator), the engine might stall." — Mercedes-Benz
Mercedes says the vehicle can be restarted, but a stall in traffic is dangerous and the driver will have no advance warning.
Mercedes opened an investigation in March 2022 after receiving reports of stalled GLE/GLS vehicles.
Engineers found abnormalities that occurred during automatic transmission shifting from 7th to 6th gear. But there was no known connection between engine stalling incidents and the shifting abnormalities.
In May 2023, Mercedes finally succeeded in duplicating the problem on a single vehicle and recorded relevant data with an installed data logger.
Engineers determined the reported stalling could only occur in certain GLE/GLS vehicles equipped with certain 6-cylinder gasoline engines and certain 9-speed automatic transmissions.
Mercedes-Benz is aware of 261 field reports received between December 3, 2019, and February 6, 2024, and 730 warranty claims received between May 6, 2019, and December 5, 2023.
Mercedes expects to mail recall letters April 16, 2024, but owners may contact customer service at 800-367-6372.
