There's no way Jax is T, this whole show is about Jax moral conflict and how he's trying to make this criminal organization legit, he's not an E as outside of his small circle of people Gemma,Tara,Opie his interaction seems limited, he's a writer and he's introspective, S/N could be 50/50 but I lead towards N because he mostly acts on intuition and gut feeling, P no way , he's too efficient and reliable to be a P, I mean ESTP is the complete opposite of how Jax Teller is portrayed.
To some of the others, what makes Tara an F, she has a big problem with expressing her emotions, she seems stiff, cold, and logical, she seems like the braniac nerd, trying to fit into a world she doesn't understand, very similar to GODfather with Michael Corleone, if you've seen the last season INTJ makes even more sense.
Clay is the prototypical ESTJ crimeboss just like Tony Soprano, charismatic, family man by the book, plays by the rules, but is ruthless, and cutthroat
Gemma is ENTJ to a T, ETJ are just no brainers, I go with N over S as like Jax she makes decisions purely on intuition and gut feeling, she's calculating and always a step ahead, she's just like Tara except more extraverted.
Opie is ISFP but ISFJ is also logical, but ISFP fits more as he isn't heroic enough to be a J he doesn't really have the ambition to lead or really be a part of the gang, he seems like the sensitve brooding loner type that would rather sit in his room and paint , but he's been forced into this biker gang, an ISFJ would have more pride in the club, Opie doesn't really know if he wants to be apart of the Sons.
How is Juice not ENTP, he's a quirky tech guy similar to Tony Starks, he's outgoing but comes across socially clumsy
Uncer is ISFJ I mistyped as ISFP
Chibbs/Piney are both P as they both don't have any ambition to lead and seem to both kind of ride the wave, Piney likes to go off to his cabin by himself doesn't strike me as very J like, the only true J's are Tara/Gemma/Jax/Clay as they are the only characters with drive and ambition.