I replaced the front pads and rotors and noticed that the rubber around one caliper piston had a small crack. There was no fluid present.

Does anyone know if fluid will leak out of the caliper if the outer rubber seal has a crack?

In older American cars, this rubber was usually a 'dust seal', and it had no fluid behind it. But I can't tell from the limited diagrams available.

Thanks in advance for any info you can provide.

 

It's a dust shield. You could replace it without caliper disassembly.