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87 or 91 Octane

4RunnerTony

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Picking up my new 2025 TRO 4Runner Sport Premium today. Toyota recommends using 87 Octane. I have read that using a higher Octane will give you more horse power (about 20 more)and better MPG on a turbo motor and help the motor last longer. The increase in MPG should cover the higher price of the fuel. What is everyone using? 87 or 91? Or would splitting the difference and using 89 be a good alternative? Let me know your thoughts.
 

zgreen

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Picking up my new 2025 TRO 4Runner Sport Premium today. Toyota recommends using 87 Octane. I have read that using a higher Octane will give you more horse power (about 20 more)and better MPG on a turbo motor and help the motor last longer. The increase in MPG should cover the higher price of the fuel. What is everyone using? 87 or 91? Or would splitting the difference and using 89 be a good alternative? Let me know your thoughts.
I am using 91 in my Pro. Not sure of the MPG difference, as the dealer filled up the first tank with 91 as well. More HP and Torque, why not!
 

brumey

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I am using 87 per manufacturer specifications.

I went through a long term experiment with a Ford twin turbo. I used top grade in California for years and logged the mpg which became very predictable. If there was an increase in hp or torque, it was noticeable in daily driving and some of that driving was, lets say “sporty”.

The forums propagated the advice that mpg would be greater on higher octane so I believed it and used 91 for years.

I changed to 87 a year ago and guess what happened to my mpg? IT INCREASED BY 2-3.

Again, long term test, variety of has brands. I also did not notice a decrease in power or torque but I am not putting it on a dyno either.

So, for me, the increased mpg when using premium gas on a turbo engine was not true. Your results may differ but, I suggest you try both over a period of time and test. I know these results were in a Ford but still.
 
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Mudbath

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This whole topic is a can of worms - a can of worms which will be posted multiple times monthly for the foreseeable future, if the Lands Cruiser forums are anything to go by.

It doesn't make sense to me that MPG would decrease when using a higher octane (and all other factors being the same). Higher octane fuels have a lower flash point, and a modern engine is going to send the same amount of fuel through the injectors based on throttle input, not the octane you have in the tank.

Toyota specifies 87 octane for US bound 4R's but has always specified 95 RON (equivalent to 91 octane here) for Latin America, most likely as a way to safeguard against inconsistency in fuel quality in local markets, even with normally aspirated engines.

As for what you should put in your truck, you will be fine with 87. Dyno tests do show the ECU adjusts for more octane, so some of us will run 91 (or higher if your state has it). More importantly, use quality gas. All major brands now have additive packages that will keep your injectors clean. I've been a slave to Chevron Techron since the late-80's and have never had a problem
 

72and10bulls

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Picking up my new 2025 TRO 4Runner Sport Premium today. Toyota recommends using 87 Octane. I have read that using a higher Octane will give you more horse power (about 20 more)and better MPG on a turbo motor and help the motor last longer. The increase in MPG should cover the higher price of the fuel. What is everyone using? 87 or 91? Or would splitting the difference and using 89 be a good alternative? Let me know your thoughts.
Try each of them and let us know. We run 91 in the new Pro.
 

brumey

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This whole topic is a can of worms - a can of worms which will be posted multiple times monthly for the foreseeable future, if the Lands Cruiser forums are anything to go by.

It doesn't make sense to me that MPG would decrease when using a higher octane (and all other factors being the same). Higher octane fuels have a lower flash point, and a modern engine is going to send the same amount of fuel through the injectors based on throttle input, not the octane you have in the tank.

Toyota specifies 87 octane for US bound 4R's but has always specified 95 RON (equivalent to 91 octane here) for Latin America, most likely as a way to safeguard against inconsistency in fuel quality in local markets, even with normally aspirated engines.

As for what you should put in your truck, you will be fine with 87. Dyno tests do show the ECU adjusts for more octane, so some of us will run 91 (or higher if your state has it). More importantly, use quality gas. All major brands now have additive packages that will keep your injectors clean. I've been a slave to Chevron Techron since the late-80's and have never had a problem
I completely agree on gas quality and additives probably being more important. As my Ford twin turbo was direct injection, I used Techron additive until I changed to BG fuel system cleaner. I too have not had an injector problem. Of course, I hope the valves and combustion chamber is clean too but only scoping or head removal would tell me that.

I generally only use Tier 1 gas. Costco primarily.

I noticed the 4R has direct injection and port injection. Maybe that will reduce carbon build up. Only time will tell.

Its whatever makes us happy I guess 😆
 

Nodak

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well i ran 87 octane in my 2014 4R limited since day one. here are my stats over 116k miles

also attached is the spark plugs i replaced at 106k miles (those are the oem plugs that came with the 2014 4R when i bought my limited)


2025 Toyota 4runner 87 or 91 Octane 2014 4Runner MPG
2025 Toyota 4runner 87 or 91 Octane 2014 4runner spark plugs 1
2025 Toyota 4runner 87 or 91 Octane 2014 4runner spark plugs 2
2025 Toyota 4runner 87 or 91 Octane 2014 4runner spark plugs 3
 

CO/ZA

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91 if you're at altitude.

87 at sea level is fine for cruising around.

Don't bother with BG snake oil, just quality fuels like Costco, Exxon, or Shell.
 

photorunner

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I've been using 87 with the cooler weather, once it stats warming up I'll probably try a few tanks of 91 to see if there's a big difference. I previously had a Mazda CX-50 turbo, and Mazda actually has 2 sets of hp/torque numbers for their turbo vehicles and there is a decent bump in hp with the higher octane fuel. The cooler, dense air seems to be fine with 87 though, so far.
 

Archer

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Found this on another site. I'll check it out tomorrow, never noticed or cared to look.


“If you look at the gas pump, under the octane number it should say "Determined by the (R+M)/2 method". The "R" in the formula is the "Research Octane Number", the "M" is the "Motor Octane Number". So if it says that to use 91 RON the MON would be at 83 hence (91RON + 83 MON)/2 = 87 Pump Octane.”
 
 







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