This is very outdated and Im sure doesn't apply to current oils. 20 Years ago I ran Chevron Delo 400, Mobil Delvac 1300 and Shell Rotella T 15W-40 in a 1999 Cat 3406E in a dedicated route. With 30,000 mi drains (Max allowed with UOA) and 2 gallons of add oil (Roughly 20% of capacity) the TBN was at 50% of new and viscosity was slightly below new (No thickening). Soot was very low. All three oils performed essentially identical. It consumed slightly less Delo and at the time it was slightly cheaper so that's what I ended up running for 30,000 mi OCI. Truck was sold with just shy of a million miles. Oil consumption had increased 50% over roughly 900,000 mi.
I don't follow - what is outdated?
Synblend? -----> https://www.mobil.com/en/lubricants...ants/products/mobil-delvac-1300-super-15w-40/