This is related to the M1 0w40 and how stable it is thread. As some of you know I have a 2000 Prelude with the H22a engine that starts to use oil at about 4,000km into the interval. Until 4,000km it will use maybe .25L if any. After 4,000km it will use about 1L/1000 miles. I always used M1 5w30. Used 10w30 on the last interval, same results. My question is this: is this consumption caused by the oil thinning out during use? Is the problem the 3.0 HTHS number of the oil or the fact that M1 is on the "thinner" side of 30w? Are the HTHS and weight related? I am going to experiment with the M1 0w40 for this interval and see how it holds up after 4,000km with the 3.6 HTHS and 14.4 cSt. If my theory is correct I should see reduced usage if any. What do you guys think?