Actually, I watched a YouTube video back in the day with one of the lead Land Cruiser engineers. He said regular gas will work just fine with Land Cruiser and will not harm the engine whatsoever. He said premium was mainly stated to keep the Land Cruiser a "premium brand" and to help fuel efficiency standards.
A link would be educational. By “back in the day” are you referring to 2024 with the launch of this platform, or earlier?
I have no doubt our Land Cruiser would survive on lower grade fuel than I have been feeding it. I suspect something has to give if all it ever sees is regular. When I think of premium brands of SUV, I think Mercedes, Range Rover, Porsche etc. rather than Toyota (or even the GX550 which shares a few things with the LC250 platform), but am open to hearing content from the people who birthed the LC250.







