Among the manual transmissions would be the Wilson pre-selector, launched in 1930 utilised for a planetary gear process to preselect gear ratios by working a little lever around the steering area.  sebaiknya tukar minyak gear dahulu,kadangkala air masuk kedalam gearbox menyebabkan minyak gear bercampur air dan menyekat gear dari bekerja https://gearboxauto69358.mybuzzblog.com/13499507/the-2-minute-rule-for-gearbox-auto