Hi,
I recommend Unhappy Teenagers by William Glasser
I believe it applies to all ages. The message is that your only influence is a good relationship where he feels understood and sees you as a help. problem solving focuses on both yours and his concerns , by talking and chatting with him like you would with a friend or your neighbours 25 yo child he will start to see you as a person who also has needs. it is a process that he needs to learn to trust , that cooperation is the way , win-win , not win-lose.
I think Byron Katie is helpful in a liberating way , getting rid of our fears and emotional baggage and related suffering so we can relate to our child in creative ways and lots of patience. Not easy
Allan