Running Dot5 brake fluid
 

I had the hood open the other day and noticed that my brake cylinder resvoir was a little low. I accident filled it up with Dot 5 fluid instead of dot 3 fluid :( will my brake system be ok or should i get it flushed immediatly? thanks -alex

You shouldn't be mixing Dot 5 with Dot 3. If you plan on switching to one or the other drain the whole thing and fill it up with one or the other.

If it's DOT 5.1, you're fine. Otherwise, no, DOT 5 is incorrect for the brake and clutch system. You'd best change the fluid with the correct DOT 3, 4 or DOT 5.1 (NOT DOT 5) as soon as you can.

Do a search on dot 5, this is another one of the topics that has been beaten to hell. ONLY use DOT5 if you're redoing your*ENTIRE* brake system. Use it only if the equipment you're using has never ever ever ever had any breakfluid in it (all new parts).
Why? Dot 3/4 won't mix with dot5. This + the fact they compress at different ratious, maens you're going to create a braking bias on your car if you mix the two. If theres soem residual dot3 on the Front left braking lines, you can expect that tire to be braking diferent than the front right, which may have been properly drained.

All in all, don't use it unless its a new system...

Just drain and refill - if you can't do it yourself bring it somewhere as it's a pretty idiot proof procedure.