I've shared this story before, but here it tis again. I have never had any oil related issues with new thru high mileage vehicles. I change it on most of our fleet (9) with Walmart oil of the appropriate weight. On my '51 that's 15w40 diesel oil. It used to be made by Quaker State, don't know who makes it now. I change it once a year (or so). I do drive it to town at least once a month year round. That's a 40 mile round trip, minimum.
My highest mileage vehicle, bought new in 1995 is a Dodge 3500 with a Cummins 5.9. It's got right at 300,000 miles. I used to drive it as a work truck while pipelining. At about 75,000 miles I installed a Frantz by-pass oil filter and bought several John Deere oil analysis kits. Plan was to start changing the oil when the analysis said it was time. Well at 15k the 15W-50 Delo always came back good to run, but I'd change it anyway. When the truck was somewhere near the 200,000 mile mark I decided to not chicken out and go till the analysis said change, well I chickened out at the one year mark with 23,000 miles on the oil. It was good to run with all the numbers well within acceptable range.
When I had the oil test above performed I also pulled a sample on the wife's '98 Dodge Dually, also a diesel and with no by-pass filter. The Delo 15W40 oil came back good to run at 13,000 miles. I changed it.
My point is, I believe that for a normal vehicle (no race rigs) about any oil is sufficient this day and time as long as it's a modern, mainline brand in the proper weight range.
I believe we change oil way more often than truly necessary, especially when it comes to our pampered babies whatever they may be. But hey, it's nobody's business so do what feels best and no apologies needed.
The attached analysis isn’t the one mentioned above but the one immediately before the 23,000 mile sample. My filing system could use some work. RonR
