Brake Fluid Change A brake fluid change is required every 30K miles. This is to change out fluid but to flush out debris and water contamination. But I do suggest about every 60K to 100K miles you break down the calipers and wheel cylinder and inspect for debris and rust. The reason why you need to bleed the brake system often is that brake fluid is hydroscopic absorbs water) and reduces the boiling point of the brake fluid. So the next ti