I don't have a Toyota so I've also wondered if it's good to run in my Ford's or Mazda that call for 20wt.
It's an API licensed motor oil and has the API Starburst on the bottle. You can run it in any gasoline engine that calls for 0W-20 if it doesn't stipulate additional OEM approvals like Land Rover/Jaguar or Daimler MB229.71. However, this isn't the case for your typical Ford or Mazda engine. You will be fine.
I've thought of adding a quart (or half qt.) of Mobil 1 0w40 to it (a Caterham blend) to 'thicken' it up a bit. One of these days I'll use it.
You will not gain anything by doing this, and in fact, you might hurt the oil's ability to do its job. I remember back in the day when truckers that knew Lucas Oil Stabilizer was bad were supplementing their Diesel oil with Gear Lube to "thicken it." Could I talk anyone out of it? Nope. It's not a good idea, but if you insist on doing it, I can't stop you. Will it damage anything? Probably not, and to some degree, the two oils should be compatible.
PS: There are some guys on this site who think they're the BITOG 'police'....rather than answer the question asked they respond by pointing out "that's been asked before" or "use the search function". I don't understand why they don't either answer the question or ignore the post.
Not the core members of this community. They are very knowledgeable and courteous. Usually, it's new folks who either joined recently or stop by here only once in a while. It's usually someone who uses your curiosity against you so that they can vent their own frustration or blow off some steam at your expense. Don't think too much of it, and as long as they're not too insulting, ignore them.
That's nearing Redline territory.
