I have been hearing this noise for quite a while. When I slow down to turn a corner or come to a stop, I can hear this rattling noise. When the speedometer hits 20 mph, I start hearing the noise until I come to a stop. I was driving to my driveway at 12 mph and I could hear it constantly. I just had it in my shop and found the driver's side axle u-joint throwing a little rust out. I replaced upper and lower ball joints and the u-joint. Heading down the road today, the noise was still there. I am thinking about removing my front driveshaft, but had it rebuilt last year. Anyone have any other ideas? It sounds like it is in the left front area of the truck. Thanks.