Go with 5w-30. 10w-30 is to thick for the tighter clearances in these engines
Have you ever look at viscosity of the oil at operating temp and compared them? There are lots of 5w-30s that are thicker than 10w-30s at operating temp, however the real difference in them it the thickness at 0 degrees. They are all tested at 0 degrees c and 100 degress c.
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