hello there, last week i checked my cars(e320) transmission fluid, it was around 1kg less than the required level so i just simply add that much to the existing fluid.how much bad can that be, since i believe the added fluid will have different parameters(viscosity, etc...) since it is new than the old one(used).so to sum up the idea, can transmission fluid be added or it has to be totaly replaced?

__________________
I HOPE IT WAS CLEAR!!!