Adapt parts in assembly !

Is there a way to share sketch/feature parameters betweenparts in the assembly
Ex. If I manually change the diameter of the pistion, I want thecylinder diameter to be automatically changed accordingly to thepistion diameter
Or maybe there is a better way to do this to get the same resultsand I don't want to use excel table to drive the part parameters

Thx, ChrisSolidworksGeneral