My son bought a 99 Forester with 140k on it. He wanted to service all the fluids after he got it. When it came to the transmission he went to Auto Zone and picked up a Fram transmission filter($22) and 5qts of Castrol Dextron/Mercon ($30). Upon changing the tranny fluid and filter the car started shifting hard between gears when it was cold but after it warmed up it was fine. I searched this site and a few people suggested that the factory Subaru filter was actually a better choice.
So I stopped by Subaru and picked up a OEM filter 38325AA032 ($35) and picked up 6qts of the Coastal Dextron VI($40). After changing back to the OEM filter and draining the tranny again (5 1/2qts total), it works perfectly fine even when cold.
Save yourself time and money and get the factory transmission filter. IMHO
So I stopped by Subaru and picked up a OEM filter 38325AA032 ($35) and picked up 6qts of the Coastal Dextron VI($40). After changing back to the OEM filter and draining the tranny again (5 1/2qts total), it works perfectly fine even when cold.
Save yourself time and money and get the factory transmission filter. IMHO