what weight oil are you supposed to use in the Transmission? Is it 80 -90?

Also where is the transmission oil cap? Or the hole to put in new oil? I swear... unless last night I was trippin really hard... I can't find it...

And what other steps should be taken while performing this maintenance?

It depends on which type of transmission you have. Are you talking about a manual transmission or an automatic transmission? The owner's manual tells you what weight of oil to use.

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Richard
http://www.whitetyphoon.com/impreza/