Why? You show excellent results with the M1 0w-20 and Pureone for a 5000 mile change. I would go 6000 miles with the 0w20. You car likes it and gets excellent results with it. I think 9000 miles is too long for about any oil in my humble opinion.
quote:I totaly agree with this post.
Originally posted by Schmoe: For 9K, I'd go with the "regular" M1. From what I've been reading, the R version is not designed for extended drains, hence the low HTHS, but for actual racing type of conditions that get changed fairly often.