2023 MERCEDES-BENZ Gla 250

[XXX] we were driving to San Francisco. Traffic was very light because of the upcoming Thanksgiving Holiday. We were about 1000 feet from the toll plaza, driving at 50-55 MPH. There was a car behind us about six car lengths back. There were no cars in front of us between us and the Toll Plaza. Nothing at all. There were no cars in lanes to our left nor right in our vicinity. Suddenly our car made a loud GROWLING noise and the car jammed on the brakes! My wife screamed but we did not come to a complete stop. A bright Red Triangle appeared in the center of the instrument panel. Then it stopped and we drove on because there was the car behind us approaching quickly. I believe he swerved and went around us but I cannot be sure what he did. I just know he did not hit us, thank God! Prior to going to the Dealer, I notified the Dealer and MBUSA Customer Service on a 12 minute call of the problem. MBUSA said they would notify the Dealer and get back to me to investigate. When I arrived at the dealer the NEW service person and I gave him my outline in writing of the event. I had emailed it to them the day before. He said that I would be charged $255.00 to diagnose MY problem even though my car is under Warranty and purchased from THIS Dealer. They had not been notified as MBUSA said they would do. I asked to speak to the Service Manager, Oscar who I have known for 20+ years, and he apologized for their error. I received an email from MBUSA about a week later asking me if I needed anything from them. MBUSA seems very unconcerned about this EXTREMELY DANGEROUS INCIDENT and that is why I decided to file this Report. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)