Hey everyone,
I’ve got a 2.5L non-turbo Mazda CX-5 (Skyactiv-G) and I’ve been going down a rabbit hole trying to understand oil choices.
My manual says 0W-20 is the required oil in Canada/US, but it also mentions 5W-30 as an acceptable option. I’ve always heard “thicker oil = better protection,” especially in hot summer driving.
Here’s where I’m confused:
0W-20 seems really thin
5W-30 seems like it would protect better in heat
I do mostly highway driving (long trips, warm engine temps)
I don’t care about fuel economy, I care about engine longevity
From what I’m reading, Mazda designed this engine specifically for low-viscosity oil, but I still can’t shake the feeling that 5W-30 would be “safer” in summer heat.
Am I overthinking this and should just stick with 0W-20 year-round, or is there actually a case for switching to 5W-30 in hot months?
Would appreciate real-world experience or technical explanations from anyone familiar with Skyactiv engines.