OK, before you guys get out the welding wands, I did search, and while some of this has been addressed in pieces, I didn't find all my answers. I wanted to throw this in front of the lubehead community for comment. I've got a new F250SD V10 6-speed, 900 miles right now. Taking it to Cape Hatteras (NC) to play on vacation next week. When I get back home, it will have roughly 2100 miles on it, including about 50 in 4WD in the sand. I figure that would be a good initial change marker. Tentative plan is to go to Mobile Delvac One synthetic with an M1 syn element filter (if I can locate one for this truck). I also plan to do an initial UAO on the factory oil. Going forward, I'll probably do another 3K change and UAO to establish a baseline for the synthetic regime. I'll then stretch the OCI to 5K for the remaining engine wear-in period (20-25K) doing a UAO at every 2nd or 3rd 5K change. After the 20-25K mark, I plan on stretching the interval to 7.5K for 2 changes with a UAO at each change, then 2 at 10K, ditto on the UAO. I believe this should give me reasonable criteria to determine the most effective OCI for the remaining life of the engine. Obviously, if I see readngs going out of control on the UAO at any of the 7.5K or 10K intervals, I'll immediately retreat to the next lower OCI. I realize that I'm sacrificing the ability to test different oil & filter combos, but that introduces more variables than I want to play with. If my brief reading of this forum unearthed any consensus, it is that the M1 syn products are good in an absolute sense, and probably the most cost-effective products to use in a modestly extended OCI program. OK, I just put the asbestos skivvies on. Thoughts?
-Scott
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