"I think the answer youwill get to this inquiry is that this site is dedicated to fuel economy only as a point of simplicity."
This is the correct answer. This topic gets brought up every now and then and while I personally would welcome the ability to track these things, the admins have said they would rather focus on just fuel consumption and not overall cost of ownership.
It would be very misleading overall, some cars would cost 1000's more and people do different miles. Not to mention the wasteful Americans who seem to change thier oil every 3000 to 6000 miles, where as a super efficient European car doesnt can do 30,000 before it needs a service.
I just keep all my service receipts etc, could add them all up if I wanted to but its painful!
Some of us "wasteful Americans" change oil per makers' schedules. My Tundra pickup, per Toyota, requires an oil change at 5000 miles (2500 if I use E85 fuel). My wife's Outback, per Subaru, has oil changes at 7500 miles. Please be so kind as to inform us which "super efficient European car" allows 30000 miles before needing an oil change.
I also drive a Chevrolet-based small school bus. It has no specified oil change interval, but has an engine-computer-driven "change oil" light. The manual says if the light doesn't come on within a year, an annual oil change is required.
I also drove a semi (articulated lorry, I think is Brit-speak). It called for oil changes based not on hours or miles, but on fuel used. It worked out to an oil change at somewhere near 20000 miles, but it used a lot more oil than do passenger cars. We also have Diesel buses at school. The one for which I know the numbers calls for oil change at 8000 miles or 200 hours, and holds five US gallons of oil.
30000 miles on an oil change, if the car is driven the US average of 12000 miles per year, would be an oil change every 2 1/2 years. I suspect the owner's manual will still call for an annual change.
I drove semis too (USA), and the oil change interval was around 30K miles, although some companies would do 15K. Fact is diesels have a longer recommended interval between oil changes than gasoline engines, because diesel fuel acts somewhat like a lubricant in the engine in ways that gasoline does not. But most Americans are obsessed with oil changing. I usually run between 7500 and 10000 miles between oil changes, but I also use a full synthetic oil. Americans are in general trained to be less conservative with petroleum products by the artificially low prices we pay for them relative to most of the world. So we are trained by these market forces to be wasteful.
I used to have a Winnebago LeSharo, which was a small motorhome based on a Renault chassis. It had a 2.0 liter turbocharged Diesel, and called for oil changes at 3750 miles. This was before the US started requiring low-sulfur fuel. The owner's manual said if the vehicle was used in Mexico the oil change interval was 1000 miles, because the fuel was said to be poorer.
My 2012 Tundra uses synthetic oil, 0W-20, and calls for oil changes at 5000 miles even with the synthetic.