I need to change my front brakes and when I'm done I'm going to bleed all four brakes to make sure there is no air in the system. Last year I had a tire shop do a brake fluid flush because I have an 05 honda element and the brake fluid was getting pretty dark and my manual said to flush the system every 3 years. I know they used dot3 but I dont know what brand. I have two bottles of honda brake fluid. Is it ok to just bleed a little out then fill it up or is mixing brands bad and should I bleed the whole system?? Also if I should bleed the whole system how much brake fluid does that take?