Try http://www.swepcousa.com The only gear lube for Mazdas.
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Dick am I missing something? I didn't see a GL-4 lubricant. For sure in the tranny you want a GL-4 lube.

I've used Amsoil for many years. They make a GL-4 for trans, several GL-5's for the rear end, and a 20/50 racing high end engine oil, all synthetic.
Some seem to have problems with Redline in the tranny, I've used MT90 lots of times with no issues. For sure don't use MT or MT90 in the rear end as Eagle7 said. Mobil one is used by many but I'm an old Amsoil dealer (since 1981) so I stay as loyal as practicle.
I know Jim Susko has a tranny oil he swears by, can't recall the name it could be a swepco product.