NHTSA Complaint #11450111 — 2017 CHEVROLET CAMARO

I began slowing down for a traffic light and experienced what felt like a car hitting me from behind. The problem is, "no one was behind me". A few days later I began noticing a distinctive shutter between 40 -70 Mph. under my seat, " It felt like I was going over rumble strips . I began researching this issue and learned that GM issued a Service Bulletin ( 18-NA-355 ), and the problem is a "known Issue". My question for my Senator is this "why wasn't a recall sent out"? Apparently a major car makers can get away with designing, building, and marketing a product with know problems which could lead to more serious issue. Since the issue deals with the power train, transmission safety, and the safety of the drivers , "How was GM permitted to simply issue a service bulletin? I followed the instructions and the dealership did not want to complete the work, "I had to write to GM and ask them to mandate the service on my vehicle. After the service my vehicle ran ok for a while, "but now I have strange shifting, slipping, clinking, and a violent jerk at times. How can the NTSB allow a vehicle with issues on the road? Again, this is a question for my Congressman and Senator.