While doing a routine inspection on my front suspension, I noticed that the sway bar end links have rubber bushings on either end. I expect that they are supposed to be fluid filled. I squeezed them and noticed no "resistance". They felt empty. Is this normal or is it time for replacement?

I was inspecting the suspension because my ride isn't as luxurious as it once was. I can't really pinpoint any clunks or vibrations, it just doesn't feel as smooth anymore.