I realised that whenever I drive very very slowly, especially during reverse, there is the above stated sound, seems to be coming from the back. This sound is so intermitten that I can't really source the problem. It comes regardless whether my Toledo's clutch is engaged or not.
What the distributor's mech said that it could be brake dust since our pads produce a lot of dust. He said that it usually happens during reverse since the car is now going the opposite direction and could be rubbing the accumulated dust.
Could it be other problems?