I think that seeking for a common time as a kind of extended object is like looking for a Philosophical Stone. If anything, time is a set of relations among objects and their states in space in a similar way as traffic is a set of relations among cars and their states and roads. Needless to say there is no such thing like traffic on its own, but most people believe time exists as an agent facilitating change without regards why and what is changing, and why sometimes is not changing at all.