Definitely run toyota mini truck axle.  They are great.  Very reliable once you beef them up.  I never broke anything in my front axle and i run a detroit up front as well.  And we wheel the hammers, rubicon anywere in the southwest, with no problems.  Anything over a 37inch tire i would step up to a 60 but with 37's your good.  Also would recommend highsteer, longfields and longfield hub gears as well.  Its a proven combination that works pretty much better than a stock 60.  Also the narrower toyota axle seems to get through some tight spots a little easier