While driving on the interstate and coming over an overpass there was unavoidable debris located in the road. Immediately after passing over the debris there was a loud noise followed by jerking and the RPM’s revved up almost like the car was in neutral. I let up off of the accelerator and then tried to accelerate again. The car would not go faster than 30mph and will not shift out of 3rd gear. I had the car towed to the dealership and the diagnostic codes reflected vehicle speed sensor and there was no physical damage that was visible under the car. I was told that the problem was in the transmission and that it would need to be changed and given an estimate that totaled over $10,000. I was also told by the service advisor that this is a known issue with the Infiniti Q50. After doing researching this a common problem and the consumer is having to pay out of pocket if the warranty has ended. This incident could have ended badly while doing 70mph on the interstate and the car just quits moving. With all of the complaints that I have read over in regards to the transmission issues yet no action has been taken to investigate this problem. It is obliviously a manufacturing issue and the consumer should not have to pay out of pocket for defective transmissions. This luxury car was not a cheap purchase. Very disappointed that with so many cases an investigation has never been done. Infiniti should be held accountable and a recall should be issued for this problem. I will not stop until I can get through to someone that can help.