hey all i went to the track last friday and since then there has been like a clickin kinda sound sometimes when i start and shift gears, my first thought was cv joint or axle but i got under the car tonight and it almost sounds like its inside the mid shaft or the tranny. like the differential part. when i spin it it almost feels as if its not a solid contact, like ill start to spin and all of a sudden CLICK it catches. neone have ne idea what could be wrong? is this ummm "slack" normal?