Looking online at the Viscosity index of some oils, i've come to the conclusion that ELF and Total who are one the same are on top with a VI of 186..

Compared to an average of 160-170 from other brands..

Just curious to know what ya'll use on 'ere!!

mostly castrol products . our machine shop told me that there is better oils, as a comment one day , i have handed him 2 cranks to measure up for machining to have him hand them back with the comment , that's a sign of good oil for you.

I seldom worry about the brand, I just check the engine (or whatever) oil spec meets the requirement and with ATF whether it is DexII or DexIII that is required. On the VI front 170 to 186 I doubt would be noticably different in our temperate climate. A few years ago I was left with a quantity of hypoid gear oil that was SAE 140 instead of the more usual 80/90, I took advice at the time and was told I would never notice the difference, so I have used it up over the years in all my Land Rovers. He was right, I never noticed the difference. Much more important to change the oil regularly and systematically before the additive components break down.