There is quite a bit of evidence that there is a compromise in wear
protection to obtain the mulit-viscosity. We switched to 100W for the late
spring, summer, and early fall. It was no big deal, just pick up a
different case and put a note on the old one in our locker. It's probably
only a small wear increment but it made me feel better to have the best oil
in the engine during the hard flying months.

--
Roger Long