At my dealership we use the following procedure:
-Drain from plug, then remove pan to get extra quart out
-Replace the internal filter assembly
-clean the inside of the pan and the magnets
-install pan and fill with 5.4 quarts of fluid
-run in forward and reverse gears several times on the lift to get new fluid in all internal areas
-drain from the plug only
-refill the the correct amount of 2.6 quarts
-reset the fluid degradation counter with the factory scan tool
I'm pretty sure we charge $379 for that. On the other cars that all have external filters, we offer an increased version of the service that replaces them as well.
We do these services so often that the fluid occasionally goes on backorder and we have to use an extremely high quality aftermarket fluid made by BG.
Mitsu master tech since 2009, German car guy, recently bought a 14 Mirage 5spd with 145k. Youtube Channel
View my fuel log 2014 Mirage ES 1.2 manual: 30.5 mpg (US) ... 13.0 km/L ... 7.7 L/100 km ... 36.6 mpg (Imp)