Hi, I'm the second owner of this sonata and it's in 70k. When the engine is cold and the car comes to a stop, it gives a big jolt when downshifting, at lower speeds. I took it to mechanic of the previous owner and that mechanic told me to change the transmission! I just got the car and I don't know what to do. Since I am a female, I have no idea about cars. If anyone can help I will be so happy. Thank you so much in advance

 

There is a trans control module and Ecm
update available for this concern . Can only be done at dealer using a gds scan tool.