Use oil with mos2 ? in 4A-GE engine

[Mux213]

Ryo,

Don't know those oils sorry.

The problem with switching to synthetic or semi synthetic on an older engine is related to the better quality of the oils. They are thinner and usually have additives to dissolve any dirt that's in your engine.

If you've ran the engine on mineral oils for a long time the thinner oil could result in clearance problems as the engine is fully run in on a thicker oil which could lead to oil leaks or worse.
Also having all the dirt that's build up in the engine for years suddenly come loose could clog up important oil channels resulting to damage to your engine.
Both off course are risks, frequent oil changes and good engine maintenance probably results in no problems when switching to better oils.

If however the engine has been running on synth or semi synth for a long time it would probably be best to stick with it, they generally are better for the engine then mineral.

I used Valvoline 10w40 for the longest time in my Hachi (not max life, not sure what it was called), but as far as I am aware, my Hachi never run on anything but mineral oils.