A JATCO JF506E (relabeled by Mazda as 5F31J) 5 speed automatic? My 2003 Mazda MPV is so equipped; the OEM fill was Mazda M-III, a Dexron II clone. The 5F31J is a common maintenance problems in 2002-2006 MPVs; it often fails before the 100K mile mark.
In an attempt to forestall such failure, I change my ATF using a cooler line flush every 30-35K miles. Given the OEM fill, I used Dex/Merc in my first two ATF changes but my most recent fill is Dexron VI augmented by Lubegard Red, which works well.
It is hard to believe that Mazda M-V or some MC equivalent contains any secret sauce as far as the JATCO JF506E is concerned.