Team Building Tips

I was hoping to get some feedback on one of my teams. There are some very strong personalities that have clashed previously. Currently the team atmosphere is very combative (maybe this is too harsh of a word), but everyone watches what they say, there is eye rolling when each other talks and a lot of back talk. I wanted to regroup with the team and somehow kick the team off to a different start (these individuals have been working together for over a year). Any suggestions? Would doing something like Myers Briggs or SDI help? How can I get the team to work together rather than against each other? Thanks for listening (or I guess, reading).