I was wondering if a lower viscosity oil would be advised in this engine, mostly for lower startup wear and improved fuel economy.
If no one has tried it I am willing to give it a go, since I just bought a 12-pack of oil sample bottles!
It would be interesting to see a UOA with this oil in your Toyota however I anticipate that you will have slightly higher wear with a Xw-20 motor oil than you would get from a 5W-30 or 10W-30 motor oil.
zoomzoom just did a comparison with different synthetic motor oils with his 2000 Mazda. See this thread. BOBISTHEOILGUY UOA thread
[ May 20, 2004, 11:47 PM: Message edited by: Sin City ]