Break Fluid DOT3 or DOT4

[tonymz]

Hello all surfers,

I need to top up my break fluid but I don't know which type of fluid to put, is it DOT3 or DOT4? does it make a difference if I mix them? How would I know which one is there now? The car came with this fluid and it has never been changed.

[BUSHWHACKER]

I think Dot 3 has been replaced by Dot4 anyway. It's o.k. to mix them, but even better to replace all the fliud with new.