I have two brake systems I need to bleed, one with DOT 3 and the other with DOT 5. I've already done the DOT 3 one so if I empty and clean it out real well can I use it to bleed the DOT 5 system? Thanks for your assistance.
I would be concerned of contamination, when going from DOT 5 back to DOT 3 afterward.
That silicone based stuff is hard to get rid of. You may contaminate a few systems afterwards, even if you think you have it cleaned out well enough.
When it comes to brakes , better to be safe than sorry