Is there a way to animate a extrusion. I'm trying to show oil flowing through various engine parts (tubes). I obviously need to contain this to the tubes the oil will be flowing through. I thought a simple way may be to animate a cylindrical extrusion, shaded, within the tube cavities. I'm not familiar enough with Maya fluids or RealFlow to know how, or if, they handle this. Some of the areas are pretty irregular shapes.