Engine oil OEM Mazda or AMSOIL

For me amsoil signature series 0w20 a lot better than ravenol ehs 0w20.

I'm regularly using amsoil ss on my Honda L15z1 engine almost 7 years.

0W-20 Amsoil Signature Series 100% synthetic oil changed every 5k miles. Wix 57173XP filter.

For Naturally-Aspirated Skyactiv engines, it is highly recommended that you use Mazda's own(Idemitsu) high molly GF-5 0w-20. Arguably it is one of the best oil for skyactiv engines.

As an avid user of AMSOIL, it’s a noticeable difference, amsoil is the king

With Amsoil even if it's not signature series I trust it more than any other 0w8.

I run Amsoil and my oil change interval is 25k so the answer is it depends.

I only use Amsoil Signature Series in my B58.

I changed to that and really happy with it so far, shifting is butter smooth.

Many reputable rotary shops have tested numerous oils over the years, and agreed that the bearings do not have adequate protection with 5w-20 or 5w-30, especially if you track the car or do any spirited driving regularly.

personally, I think Amsoil AFL is junk. They ruined a stout oil when they reformulated it to mimick 505.01.