Engine oil OEM Mazda or AMSOIL

I also wouldn’t run motorcraft period in my 5.0, in the words of a friend who’s a master mechanic “they sell cars not oil”. Just some food for thought, I did run it until he gave me this one line, I now run amsoil and my 5.0 and 6.2 and 3.0TT are all much quieter, for what ever that’s worth

Me running 5w50 Amsoil SSO full synthetic or 0w50 Eneos or 0w40 Amsoil SSO if being used in winter (down to -40F, and yes, I've driven these cars down to that cold)

Synthetic is better, always. Higher not viscosity has better shear protection. A good additive package that has great shear protection lets the housings wear slower.

This is the second time I had put Amsoil in my scooter and I had to post the findings over here for my fellow scooter riders here.

The performance jump is noticable, my access now pulls pretty graciously post 60 km/h before it was more noise and less acceleration with Castrol 5w40 synthetic. You can feel the acceleration in your bum and hands when you twist the throttle after 65 or 70 which is where most if the 125 cc scooters flat out due to lack of power.

Even doing top speed for more than 1 hour in highways you will feel no vibration thats how smooth the engine+Amsoil combo is.

The smoothness of this oil with this suzuki engine is next level my friend who borrowed my scooter for a day (apache rider) said it feels like riding an electric scooter that's how smooth it is. So do try!

I use Amsoil SS mainly because I do long drains, over 20k Km. So the price of the oil is not a big issue.

Great oil but worth it only if you do long drains.

2014 3, 0W-20 full synthetic (whatever major brand is cheapest) from brand new, every 7500 miles.

170k, runs like a top, burns not a single drop between changes, compression and fuel mileage exactly the same as new.

I literally just changed my oil today, I love it, I have been using AMSOIL directly for years now with free shipping and free membership if you spend 500 a year or more if I recall correctly.

I use AMSOIL signature series 0W-30 but the Mobil-1 suggested by others is totally fine — AMSOIL is awesome but is expensive.

I ran Amsoil in my 2002 7.3 for years and it worked well for me.

For the record, this is NOT the exact replacement to Mazda 0W-20 GF-5 with Moly - Synthetic Engine Oil.

While this has high molybdenum, it's still a different formula from Mazda's own proprietary blend.

Those guys don't replace you crush washer, and the oil the use is crap.