Sometimes when I put my car in gear or (rarely) when it shifts (little harder than stock shift) I hear a metal clunking noise which sounds like it's coming from the rear of my car. It sounds aluminum which makes me think it's the driveshaft u-joints. The input shaft into the rearend is solid, and the driveshaft twists a miniscule amount when I'm under there with both hands turning. Could either end of my driveshaft be where the noise is coming from? and would replacing the u-joints fix this? ya i know it was probably something I should have done before swapping this driveshaft in....