assalam alaikum sir G....ur information is very great for me,but i m confused on my car,,i have cressida1987 model box car.1 C 14 gear.and 11,43 diffrential,,above120 speed it want more gear for smooth drive..i change 10,41 differnatial,and it s better. then 11,43,,can i try for more smooth drive 9,41 OR 12,41????