Finally, the transmission was replaced with one brand new. Picked up the car today. The handling now makes me remember a bit the way it drove when it was new. Expectedly, there's more torque on low gear and fuel efficiency is restored. The gear change on the automatic portion is more snappy now.
Tech said that the old tranny pressure was way below the spec of 585 PSI. He removed the valve body and saw wear on the belt and pulley.
All was a hefty $7000, "generously" covered by Mitsu.
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