Been running Mobil Delvac 1, 15-40 in the truck for a while now... always idled about 625ish rpm... changed oil today and just put the non-synthetic oil in the subject in it, went driving around, now I notice it's idling closer to 550ish rpm. That's about a 75rpm drop. Something in my mind is telling me this isn't right... now, 75rpm might not seem like a whole lot... but there's a definitive difference between the 2 oils. Don't think I like it... that tells me that there's more friction in there, which we all know is not good. Anybody else had any other experiences with this? Is the synthetic that much better, or is something not right here. Any advice would be appreciated, thanks,
Brian
(one of these days I'll bump the idle up, once I figure out how to get to the nut, but that's another day's project)
Brian
(one of these days I'll bump the idle up, once I figure out how to get to the nut, but that's another day's project)
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