The meaning of grandfather, grandmother in dream | Dream Interpretation
Vision: If you are talking to either one: you have made a wise decision, and a specific project is going to be successful.
If both your grandparents are deceased: expect to get help in a certain matter, or you have decided to live a more prudent life.
Depth Psychology: Grandparents represent the wisdom that is available to you.
If you use good judgment in the things you do, everything will turn out all right.