I've been thinking about pushing my oil changes to every 10-12k miles in the future, given that the 5-6k Kawa interval was probably decided on when only dino oils were available back in the late 80's, early 90's.
All cars here over the pond have at least doubled their oil change intervals over the past 10 years or so, both gas and diesel engined models. IMO, the only way they've achieved this is by using better available oils, especially fully synthetic such as Mobil 1.
Then again, for the time and cost involved in terms of life time ownership of the C-10, I'll probably just change mine at the end of every season regardless of whether I've done 3k or 10k. Then there's fresh oil in the engine over the winter period of zero riding
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