Watch this for final word on which fuel to use (Hint: Premium fuel matters)

[SGaynor]

Good lord this topic has been beaten to death a thousand times.

It's a very simple answer, but people just want to believe in conspiracy theories (Premium gas for Premium vehicles! It's the Government!).

Modern vehicles with cam and knock sensors adjust timing to reduce/eliminate early detonation of the fuel/air mix in the combustion chamber.

Why is this important? Because early detonation can harm your engine and late detonation is not efficent.

Lower octane gas has a lower ignition point (pressure/temperature) and higher octane is higher - it has nothing to do with "power" or "performance."

High efficiency engines (to meet CAFE requirements) use turbo charging and higher compression ratios to be more fuel efficient. What does turbo charging and higher compression ratios get you? Higher temperature/pressures in the combustion chamber. What prevents early detonation of the fuel? Higher octane gas.

So, if you use lower octane fuel, the cam/knock sensors will advance the timing and ignite the fuel before it self-ignites. However, this is further away from top dead center, which translates into less compression and less power - ie, it's less fuel efficient/power producing.

So, yes - your vehicle can run just fine on 87 octane fuel. But it will be less efficent than if it ran on 91+.

That's it. That's why Toyota recommends premium (91+). If you want to be less efficient, than go ahead an use 87 octane.

(As a side note, this is why Land Rover recommended premium fuel in the 4.6L Discovery D2 (higher compression) even though the motor was a 1950s Buick design)

 

[Madscientist]

Given this discussion, it would seem that the more substantial modifications made to the LC that adds significant additional weight, the larger the mpg difference one might see between 87 and 91/93 octane fuel.

 

[RideWithYanu]

So, yes - your vehicle can run just fine on 87 octane fuel. But it will be less efficent than if it ran on 91+.

That's it. That's why Toyota recommends premium (91+). If you want to be less efficient, than go ahead a use 87 octane.

Is this your personal opinion or do you have a source for this claim?

 

[ovʀʟxnᴅ]

Given this discussion, it would seem that the more substantial modifications made to the LC that adds significant additional weight, the larger the mpg difference one might see between 87 and 91/93 octane fuel.

There's definitely a lot of variables. I tried to keep my previous post very simple.

I'm pretty loaded down with camp chairs, a full refrigerator, a big Bluetti battery, a heavy rooftop tent and awning, 35" all-terrain tires, rock sliders, 5 gallons of water, recovery gear and tools, and a swing-out tire carrier with a full-size spare. These things all pretty live in my truck. It makes planning easy when you're already ready. Any given weekend could be in the woods or on the beach, so I just stay loaded up. My mileage comparisons posted earlier are a continuous ~100 mile trip at varying speeds of 55 mph and lower on a flat route sitting near sea level, AC running, inverter running to keep the Bluetti topped off.