ATF is what kills clutches and seals
Not because of the chemicals
But because it is a very poor heat sink without a pump.
20w-50 for long life
5w-20 for funzos
Although the oil for Prius is a very good newcomer ,they use 0w-40 which fits well with the warm-up of a moped.
This is on v1s tho, so it's also got 20oz vs e50 4-5 oz