I started noticing a week ago that my brake pedal will go soft when i hit a hard bump and then hit the brakes immediately after. If I am jus driving and hit brakes they work perfectly only when i hit a hard bump in the road will they go soft for a only a second and then apply properly. I checked the master cylinder and reservoir and had no brake fluid leaking and i was told that when the master cylinder goes bad the brake fluid will be discolored and dirty. The fluid is at normal level and is clear as usual. I'm hoping that they don't decide to give up on me all together. Oh it's a 99 1500 silverado Z71 and my abs light isn't on or anything. I appreciate any tips or ideas.