Engine oil OEM Mazda or RED LINE

Mazda says every 7500 miles for normal duty OCI, and I’ve done every 7500 miles since brand new on my 2014 3z.

It’s now at 187k flawless miles, consumes no oil *at all* (I’ve literally never had to add oil beaten changes, ever, what goes in comes out every time), runs like new, seems easily headed to 250k.

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.

I stand by Redline 5w20. Not that I have bad “hemi tick” on my 5.7 but I swear the valvetrain is the quietest when I use that oil.

I personally use Red-Line products, and it's the absolute BEST products out there. Their 2 Stroke racing no smoke oil is OUTSTANDING and 2nd to none.

Redline and royal purple filter for my 17 ram sport 5.7. 60kish on it now.

But then we replaced it with a SkyActiv Mazda3 that used 0w20 and proceeded to have a good long history with that motor that had 0 oil consumption in 125K miles; I did all of the oil changes myself and it was always 4.5qts in/4.5qts out every 5k miles.

For [Naturally-Aspirated Skyactiv engines](https://en.wikipedia.org/wiki/SkyActiv), 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](http://www.cleanmpg.com/community/index.php?threads/45295/#post-357910).

I always used redline 5w50 on my S65 runs very well and redline has a great reputation of quality oil especially for its high performance cars. Takes less time to warm up too in low temperature climates.

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.

Engine was noisier with the mix vs. the previously used redline 5w40. Iron levels are up at 6.3 ppm/1000 miles Oil usage increased by 1/2 quart over the redline 5w40 TBN/TAN levels are worse than 5w40 at comparable mileage