grassroots
10+ year member
needs car audio rehab
i'm an electrician myself, and i highly doubt they will work themselves loose... the proper way to use them is to pre-twist the wire then screw on the wire nut until two visible twists are in the wire jacket. if you install them correctly, there won't be any problems...when neverenuffbass said dont use wire nuts, he is just concerned that they will work themselves loose.
my buddy is an electrician and says this can be fairly common in an environment that has lots of vibrations. he told me, if i use them to just wrap some tape around the wire and the wire nut to keep it in place.
its just what he told me, so YMMV