The answer to this question will, of course, vary from person to person. In order to answer it, you will need to think about your specific situation and your specific grandparents. My grandparents were born in the 1910s and I was born in the 1970s. My answer to this would be very different from yours.
In order to answer this, think about some of the types of values that have tended to change from generation to generation. In addition, think about issues that have become more important or less important to people in recent times. Try to think about whether you and your grandparents differ on these sorts of issues.
Traditionally, attitudes towards things like sex, money, religion, and authority have changed over the years. These are things that you might consider as differences. It could be that you have different moral values when it comes to sex than your grandparents. If they were born in 1946, for example, they might have very traditional values in which there is to be no sex until marriage and there is to be a strong double standard as to what men can do and what women can do. If they were born a little later, like in 1951, they might be more liberal than you on this issue depending on whether they were part of the counterculture of the 1960s. The same things will be true of attitudes towards things like religion and authority. People from the 1940s might be very respectful of religion and authority while people born a bit later might not be. You might also think about whether their attitudes are different from yours on things like gay rights and abortion, both of which are much more important to many people today than they once were.
You will also need to think about things like where you grew up and where your grandparents grew up. If your grandparents grew up in a rural area or a foreign country, their values might be very different from yours if you are growing up in suburban America.
In short, what you need to do here is to think about issues like the ones I have mentioned. Try to think about how you and your own grandparents might differ on issues like these.