Lol, That's kinda of like asking someone what the best food is to eat... Good luck getting the same answer twice!
Oil with Acea A5/B5 certification. That's a tough certification that will test that oil will give good protection and fuel saving over the entire oil change interval. I would just get the cheapest known and easily available brand.
I have read the top two most popular is Toyota and Mobil 1 I have only used Toyota in the first 5 years, but I just got 4 gallons of Mobil 1 and will be switching and using that for the time being.
maybe in Finland. In the US the oil to use is any 5w30 oil with SM, SN or SN plus would be the answer. And even if the standart is covered, different oil brand would have slightly to vastly different outcome in lubrication, consumption etc. Good thing is the prius 2 isnt too picky on conventional or synthetic but i would say if you want the absolute best use AMSOIL signature or RedLine 5w30
I'm using Toyota bulk oil (purchased from service department of local dealership; I bring my own bottle), 0W20 (synth) for our Prius and a Mazda CX-5, and 5W20 (conventional) for an older Honda Pilot. No problems with either oil, both are cheap to buy (the 5W20 in particular) I don't think you can go wrong with any of the readily available oils.
At least here all oils seem to have both Acea and Api classifications on the package. I've just used Teboil Diamond Carat 0w-30 as I wanted the 0w for cold starts and that's the cheapest brand oil with the correct viscosity and a5/b5. Basically no oil consumption. Oil level goes maybe from 3/4 to 1/2 between the marks during oil change interval.
Aisle 24 right next to the best tires. The best oil is the one that's A) checked regularly and B) changed on schedule. See the owners manual for the specs it needs to meet.
ILSAC GF-5 5w-30 is the correct answer. At the time the car was built it was ILSAC GF-4 but that’s no longer certified. That’s pretty much Everything from Royal Purple to Walmart Supertech full synthetic. I like Castrol Edge myself.
