Questions...

If Premium Fuel is recommended, does it void our warranty if we use low test and will the lower grade ultimately cause engine damage or failure? I wonder because I have read that the engine management will adjust according to various conditions, one of which is fuel. Is this not the case? By adjusting, it would avoid detonation. Also, as I am not a chemist, really how much difference is there between 87 and 91 octane which are the extremes of my choices? I remember the days of leaded gas when I would buy 104 and if I remember correctly 106 octane, when the lowest was 96. A much larger spread.

Thanks again for all input.

 

look in your owners manual, in the back part of it they list all of your capabilities of fluids and such and the octane rating Toyota recommends, Toyota recommends 87 for my Tacoma, and thats what i run, Ive tried 92 bud didn't see any improvement in noticeable power or mileage

 

AFAIK, the owners manual does _not_ recommend premium fuel. It only states that you can use premium fuel if you want to. I use 87 octane. There is no reason to use anything higher than 87 octane.