I have a 2002 land cruiser, and the brakes work great on it. But I do hear a very faint but still noticeable sound that sounds like a pump working for several seconds. I hear it come on after I've used the brakes for more than just a light tap. I guess maybe it's re-building up the pressure or something? I just have never heard this on any vehicle I've driven and want to know if hearing that on the land cruiser is a bad sign, or normal. It's not a whine even, and not loud at all. But audible enough for me to notice it.