What transmission oil should I use?

Generally, for all Evo.s, use the best fully synthetic GL5 rated oil you can find for all the drivetrain (this does not include plated LSD.s or the AYC system as these require special oils). The Evo 4-7 gearbox requires 75W/85W rated gear oil. Please note that the service schedule for the Evo.s usually state anywhere from 40.000 to 70.000 kms for replacing the gearbox, transfer box and rear diff oils however, it is recommended on such a high performance car that these oils are changed sooner. Consider changing them every 15000 kms to 22500 kms or once a year. The cost is very small (45-75 euros) and you will often find that the gear change becomes better when the oil is first changed on a new car.