Engine oil Kendall or IDEMITSU

That's the wrong oil. You want the Idemitsu eco gold medalist advanced moly 0w-20, which is basically the same as Mazda oil(Idemitsu makes the mazda oil).

Idemitsu zepro eco medalist advanced moly 0w-20. Basically the same thing as Mazda's oil.

Kendall GT1 10W30 - Volvo filter 1275810

Done every 5k miles by my local Volvo specialist because that's their default and I like it to be checked out frequently. It's the oil they use. 179k miles

I switched to Kendall GT-1 20w-50 high performance and I highly suggest it. You can get 12 quarts shipped to your door from Amazon at a good price.

You don't need to add any more additives to modern day oils. You said you will be using Mazda 0W-20 oil? This is one of the best 0W-20 oils on the market. It is made by Idemitsu for Mazda. It has very high Viscosity Index of 221. Most 0W-20 oils are around 170. This means it is one of the lightest 0W-20 at start up. This is what you want in the winter.

I use to use Castrol Syntec 5W40 (what the tig came with) and all I could get here. Last spring I opened my own shop and can get Kendall 5W40 Euro and started using that as it is 502 approved. I found it made the engine run smoother and quieter. My customers have noted the same.

If you want it quiet and smooth, run 10w-40. If you want best mpg or live in the cold 1/2 the year, run 5w-30. 10w-30 is a-ite in many cases. It'll burn less than 5w-30....generally.

Kendall hands down makes the best dinosaur oil..... I run it in my BMW 2002 and my 94 2.0 ....