Hi there, I am new here too, as of like just a few seconds ago. This is one of the most asked ?'s on all of the Tundra forums. At any rate, just wanted to respond here although I know it's been almost a month. "Best" oil is subjective. Personally, as long as you use oil that meets the recommended specs and change it frequently (every 5k IMO), it's hard to go wrong really. However, I recently did some research myself and decided to switch to 5w-30 (I always use synthetic or synthetic "blend" at least). The reason I switched is that others indicated that the engine seemed to be a bit more "quiet".. i.e. less pings / tings or whatever. So far it definitely sounds better to me.
Disclaimer: This is all my opinion and in no way stated as fact, for the record. 🙊
