to check your nuts. make sure they're all there. was driving home today and started getting some nasy shaking on the highway. pulled off, and just as i came to a stop i heard a loud crash. i turned the engine off immediately, looked under the hood to find that the nuts had rattled off of my water pump shaft which holds the fan to my engine! i was amazed to find absolutely no damage! just lost the four nuts which held that sucker on. so, at about 1 am, my buddy is coming by to bring me his nuts off of his extra engine (i don't know the thread/size) and the pulley (as the bolt holes on mine got a bit of damage rattling around). someone upstairs is taking care of me.