Article on oil cleanness and fuel use
 

https://www.machinerylubrication.com...el-consumption

Its on bypass filters as much as anything- interesting.

Fascinating.

I agree with this. My grandpa had a 01 Ford Expedition with the 3v Cam phasers that everybody loves when the engine gets older (get that diesel lope going from soot build up in the engine) and he just changed his oil with walmart conventional and a fram filter every 3000 miles and that truck had 350k on it when he sold it. Running in great shape.
Remembering back to my father when he was a manager at a Terminix branch they did oil analysis on their dozens upon dozens of 1999 ish Ford Rangers and they swapped to full syn and brought the oil change intervals up with analysis being done on them and were able to get 200k out of a lot of their Rangers before they sold them with zero problems. They also did analysis on all of the other maintenance items and adjusted them as well. Transmission coolers, fluid changes, filter changes everywhere etc...