I made my decision based on lots of reading of other people's knowledge, internet hype, and a desire not to waste money. It was not because of anything I know or have experienced.
0W oils seem to be more about maximizing mpg and meeting emissions standards rather than protecting engines from wear.
Oil formulations change, so what you read from five years ago about an oil, might not still be correct today. >Have they been changed to benefit the consumer?
Everything that I have read about JGDT40 leads me to believe that it is an excellent choice, but is marketed to a price point above it's value.
I made my choice to use Shell Rotella T6 5W40 based on consistent reviews from people who analyzed it long term and showed good composition and low engine wear. No doubt there are better oils, but it is good and easy for me to acquire.
For you, Boomer', with one Boxster to dump oil in, I choose Castrol Edge 5W-50.
