There are 2 owner-reported powertrain & transmission complaints for the 2023 Mercedes-Benz GLB-Classin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
The contact owns a 2023 Mercedes-Benz GLB250. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power with the transmission warning light illuminated. The vehicle was towed to the dealer but was not diagnosed or repaired. Additionally, the contact stated that while driving at an undisclosed speed, the vehicle shuddered abnormally. There was no warning light illuminated. The manufacturer was made aware of the failure. The approximate failure mileage was 18,000.
The contact owned a 2023 Mercedes-Benz GLB35 AMG. The contact stated that while driving at an undisclosed speed, the brakes were inoperable. The contact stated that while depressing the brake pedal, the vehicle was not braking smoothly. Additionally, the vehicle failed to accelerate as intended. The contact stated that the transmission malfunction warning light was illuminated. The contact stated that the vehicle had been taken to the dealer four times. The contact stated that the first visit with the dealer regarding the brakes, the dealer applied lubricant to the brake pedal. The contact stated that the failure was persistent. The vehicle was taken to the dealer for the second and third time, however the failure could not be duplicated. The contact stated that the failure was persistent. The vehicle was taken back to the dealer for the fourth time, and the vehicle was sold back to the dealer. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 3,200.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 25, 2026