Engine oil OEM Mazda or OEM Honda

I have a Fit 2019 and switching from 5w30 to 0w20 improved my mileage from 650 km/tank to 800 km/tank.

Honda scooter oil & Castrol, tried and tested ko na. btw yung castrol ang ginagamit ko kapag summer na at sobrang init ng panahon then balik lang ulit sa honda engine oil once tapos na yung mainit na season

It'll be fine, my only argument against it is that you're probably paying too much for that quart. I've always used the Honda GN4 motor oil, buy a gallon for ~$30 when it's time for an oil change and have a little left to spare. Any dealership should carry this, Yamalube is also basically the same thing.

I would do 10k intervals in my Honda Fit but a majority of my driving in that car was highway. I'd also need to add a quart after 7000 miles because of consumption.

First gen Honda Insight, takes 2.6 quarts

23 hybrid accord, the dealership recommended 15k miles

6k is ideal.. so yeah 5k-6k. My 23 civic maintenance light came up between 5k-6k and i had like 15 % left on it

I got my 93 Accord up to 333,000 miles changing oil at 7500 miles, using the cheap synthetic blend Walmart crap, and engine failure isn't what killed the car. When I pulled the head at 250,000 miles to do a head gasket, the cylinders still had the cross hatching from the factory hone so I'm gonna say 7500 miles was plenty often enough. Changing oil more often than required is nothing but wasting money and buys you nothing in terms of reliability or longevity.

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.

I encountered something similar when I took my CE Turbo in for service a few weeks ago. The invoice said 0W20 and when I asked the service manual why they used the wrong oil they told me “oh our technicians know what oil to use, ignore that.” Needless to say I have zero confidence that the correct oil was used.