proper fill quantity
I just changed my factory tranny fluid with the OE-type QS and would like to state for the record that my '07 2.0 duratec with MTX-75 5spd was factory-filled with exactly 2.2 quarts of fluid. I believe the 2.1 value is either obsolete, a min spec or flat wrong. The same conclusion has been reached on a number of Mazda forums.
Here's how I know:
The tranny fluid in my 2007 car has never been touched until this week. I set my car on jackstands using a carpenter's level on the rocker panels and bumpers. It was level with in a fraction of a degree right to left and front to rear. Then I removed the tranny fill plug and NO fluid came out. Then I removed the drain plug and captured the fluid in a clean, dry pan. Then I measured the fluid removed using my wife's premium measuring cup. The quantity removed was found to be a fraction over 2qts plus 6 ounces. I then poured 2qts plus 6 oz of fluid into my tranny and it was topped off, no extra dripped out. For those who aren't sure...6oz is about 1/5 of a quart (nearly 1 cup).
PS: as a very last step, I poured the used fluid into the emptied new quart bottles. Sure enough, it was 2 qts plus 6 oz. My tranny has no leaks.
Conclusion: 2 qts is a whopping 10% less than the factory fill level on my 2007 Focus car. In my opinion, folks who are only using 2 qts are risking premature tranny failure. In addition, the 2.1 value listed in the factory literature is 5% less than the tranny allows and considerably less that what Ford put in my tranny when new. Tranny plugs are positioned at the proper level to allow excess fluid to drain out. There should be no reason to under-fill below the hole. If a specification ever existed to have oil filled to some level below the fill hole, I suspect this was a "safe minimum value".