truck will just shut off
driving down the road truck will just shut off.lights on the dash will come on.then it will start up all by itself without touching the key.
That sounds like a bad wiring connection, or something wrong in the charging system, that makes a lot to look at but it sounds electrical to me.
the truck now died going down the road and i have no power to anything
I don't think your going anywhere unless you get it started. It may be in the steering column, wiring, or something wrong with the ignition switch.
Looking for a Used Sierra 1500 in your area?
CarGurus has 67,929 nationwide Sierra 1500 listings starting at $1,699.
Search GMC Sierra 1500 Questions
GMC Sierra 1500 Experts