loose marble, percolater sound, 'something in a fan' sound if coming from pass side forward. No other symtoms, just the sound.
constant speed of sound regardless if car is still, or moving, clutch in or out, idle or increasing rpm, (rpm drowns out the noise. No affect if a little load is put on motor, can't hear from outside (Drown out by engine noise)
just had clutch and slave done 2k