Max life 10w40 in a D16Y7, it eliminated the oil burning in that engine to none, which indicated to worn rings, upon ring replacement, engine didn't burn oil even on 0w20.
Pre-Defy Quaker State 10w30 High Mileage w/ Slick 50 premixed.
heh.
when Defy was known as QSHM.
QSUD, QSGB, QSHM w/50.
Gone are those days.
it did fix the oil pan leak in my 05 Ranger. this was probably around 2008, haven't had an issue since and it has seen everything from 0w20 to SAE30 to 20w50.