I`ll use half and half, 0w20+5w30 Mobil synthetic. I am not use to thin oil, neither my engine, it has been working on Toyota´s Dino 5W30 oil since first service in May 2020, seven thousand Kms ago, sort of 4,400 miles. This Rav4 was made in japan, so I guess engine came with proper motor oil.
I`ll made the changes in half, just to register results, my idea is in the next four or five oil changes test it with 5W30, 0W20 and even 0w16 this in a step by step oil dilution.
First: 3 Qts. 5W30 + 2 Qts. 0w20= sort of: 3W26 (both are SN oils)
Second: 2 Qts. 5W30 + 3 Qts. 0w20= sort of 2w24
Third: 0w20
Fourth 0w16
Sixth: ? go to the one with best numbers.
I´ll make sure I share my results here.
First; The Weather:
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