Mine also went away with light braking, light turns in either direction, and climbing uneven surfaces, basically anything that would move the front tires up or down. The fix for me was the sway bar links. They weren't hard to replace, but they were dried out and rattling in their sockets. If you just pull the tire off, you can see them. If they are dried out like mine, you might give them a shot. I couldn't really reproduce the rattle just by grabbing them and trying to shake them, there was too much tension on them. But the rubber boots were gone and all the grease had dried up. Hope that will give you something else to look for!