What grade oil do you prefer?

:
2014 QX70 AWD
I know it comes with 0W-20 in USA, but I am thinking of switching to 5W-30 at the 5,000 mile oil change interval. An oil change video on YouTube by a Mazda tech on a CX90 convinced me it’s probably the correct path to go. I also used 5W-30 in my QX70 with good results.

Thoughts?
 
I normally always follow the owner's manual where an engine is concerned. I don’t care for this trend towards 0W oils, but would probably follow the manual's recommendations. I don’t know enough about the design of these engines to deviate from the suggested oil. I would definitely use a quality full synthetic oil. Luckily, both my Mazdas use 5W-30.
 
I'm pretty sure the type, brand, and formulation are all important things to consider over the basic grade to use, either 0w20 or 5w30, which are pretty close.
 
Thought this was the clip but dude didn't say much about why he went with 5w30.

I used 5w30 in my CX-3 once or twice and noticed no difference. What are the benefits for Skyactiv engines? For two of my other cars, thicker is recommended for the summer (20w50/10w40, 5w40/5w30) and for their oil-burning tendencies.
 
This is the video. He talks about how Mazda mandated 5W-30 in all turbo engines. They only recommend 0W-20 if it has Moly. My local Mazda dealer buys 0W-20 in bulk and its not the same thing. When I asked them about 0W-20 with Moly years ago after I bought my 2016 CX5 they had no idea what I was talking about. That didn’t inspire confidence. He talks about oil grades near the end of the video.

 
This is the video. He talks about how Mazda mandated 5W-30 in all turbo engines. They only recommend 0W-20 if it has Moly. My local Mazda dealer buys 0W-20 in bulk and its not the same thing. When I asked them about 0W-20 with Moly years ago after I bought my 2016 CX5 they had no idea what I was talking about. That didn’t inspire confidence. He talks about oil grades near the end of the video.

Edit: Idemitsu IFG3 5w30 is available on Amazon, but it doesn't claim moly explicitly.

Thank you for the link! This is the level of instruction I'd expect from a school.

Moly is available as an additive. I used Liqui Moly's anti-friction treatment regularly in my NA R56, less for fuel economy, but more for protection. It is also widely used at track events. I believe all LM oils are moly infused, at different levels, and they are available from Amazon and Napa stores. Zepro/Idemitsu is also moly enriched but I haven't seen them around in the last few years.

The best mpg I have achieved after 150K+ miles is with Royal Purple 0w20. Will try their 5w30 next.

I never knew that the oil supplied by the dealership during oil changes is not the same as OEM oil for sale in quarts. Was the difference evident in lower mpg or by oil sample analysis?
 
Last edited:
Hot climate and/or turbo = 5W30

Everything else is discretionary. It's fine to use 0W20 in most cases.

Agree. But it seems like 0W-20 is suggested in the US just to eke out a fractionally larger MPG rating. Most of the rest of the world uses 5W-30.

I haven’t had a turbo engine in 20 years. Don’t remember what I used way back then.
 
Edit: Idemitsu IFG3 5w30 is available on Amazon, but it doesn't claim moly explicitly.

Thank you for the link! This is the level of instruction I'd expect from a school.

Moly is available as an additive. I used Liqui Moly's anti-friction treatment regularly in my NA R56, less for fuel economy, but more for protection. It is also widely used at track events. I believe all LM oils are moly infused, at different levels, and they are available from Amazon and Napa stores. Zepro/Idemitsu is also moly enriched but I haven't seen them around in the last few years.

The best mpg I have achieved after 150K+ miles is with Royal Purple 0w20. Will try their 5w30 next.

I never knew that the oil supplied by the dealership during oil changes is not the same as OEM oil for sale in quarts. Was the difference evident in lower mpg or by oil sample analysis?
I didn’t own it long enough to have the oil tested. But I’ve never been that anal or curious about that level of detail. Some people get really into that stuff though. For each their own.
 
Back