87 octane or premium fuel

I just did a trip to my sons college 470 miles each way. I drove like I always do on the highway 65-85 mph with no regard to fuel milage. I got 19.8 on ride there using premium (93) octane, and I got 19.3 using (87) octane on way home. If it helps I think on way home I was driving a little faster. Either way I was happy with that milage. On the down side, last weekend I did the same trip in my wife’s V8 Armada and got 19.1 there and 18.9 on ride home.

 

I know I'm going to be talking about a different truck here, but I'll add it anyway...

My last truck was an '09 F150. I bought her a Hypertech tuner (great investment, BTW). Off the assembly line, the engine was tuned for 87 Octane. The Hypertech tuner had a mode to reflash the computer so it would be tuned for 93 octane.

I haven't drilled too deeply into Hypertech options for my Tundra yet, especially considering my Tundra is 14 years younger than my F150 and no doubt the computer is far more advanced. But, if you want to run premium, I would suggest buying something to flash the computer to optimally use that fuel.

 

Thanks for sharing this. This is a real-world test that I'll take at face value. I'd agree the difference does not justify the increase in cost.

 

think you are doing the wrong comparison

Annual Miles 12000

Car #1 Car #2
Fuel Price ($/gal)
2.92 / 3.42

Fuel Economy (mpg)
13 /17

Annual Fuel Cost:
2,695.38 / 2,414.12

which comes out to roughly a 11.65% savings

Savings: 281.26

Savings after ...
Year 3 843.78
Year 5 1,406.30
Year 7 1,968.82

 

Do you have a hybrid?

 

30% increase in mpg doesnt correlate into the same savings in money when you compare regular gas price vs premium gas price. you are not saving 30% in cost

 

It’s not a hybrid. 22 Platinum

 

I run a nice mid grade 89ish fuel since you realize the ethanol content of 87 is higher than published and mid grade has a slight reduction in the amount of ethanol. While premium is ethanol free, I did not notice any difference in performance or mileage going to a mid grade 89 rated fuel. I ran premium till around 5k miles.

 

Anything high performance engine, specially turbo requires 93 fuel
Common sense
Any large engine requires 93 fuel as well

 

All this chat about octane and no mention of TopTier vs non.
Toyota recommends the 87 Octane TopTier or higher.
Because TopTier matters.

 

I do what @ryanwgregg does. He puts in premium...so I put in premium.

 

This exactly but with the Ford caveat that you don't get the full HP/TQ rating unless on 91 octane. Not sure what Toyota says on this.

Using your truck as a car and not racing, 87 is the way to go.

 

Ethanol is not good for increased MPG because it contains less energy than gas but is great for Turbo motors.

Ethanol also has a higher thermal efficiency meaning when it does ignite, the temperature of the combustion is lower compared to pump gas. This allows a turbocharged engine to take more boost within a safe operating range without damaging the engine.

 

as it relates to knock sensor on 87? Like torque limit when not using 93?

 

Octane is only for pre-ignition (spark knock) issues. It has zero effect for mileage or power.

 

It is very interesting discussion. I am not so much concerned about the mileage as for the longevity of the engine. Is higher octane when towing better for the the longevity of the turbo engine

 

I just run 89 all the time! Some people say 87....some say 93. I just hit the button in the middle and never had an issue. It's worth the extra 30 cents per gallon to not be using the absolute minimum 87 in my mind.

 

my 2 cents...there is a quote in here that 87 will get you 10-12 degrees of timing retard under a hard pull but 93 will reduce that to 0-2 degrees. Mileage difference will be minimal in most situations. I've found it's easier to pull hills with less throttle on 93 on the highway at 65-75 mph. Maybe 1 mpg more. When I romp it boost gauge will go to an indicated 16-17 psi on 93. 87 seems to max out at 15 psi FWIW. My truck is bone stock with drop in TRD air filters. Makes sense as that timing gives you a little more torque under load...probably not worth an extra buck a gallon for 95% of us. If you are trying to get a little more out of the truck with high flow filters, exhaust and especially any kind of tune the yep 93 is the key.

 

Try some moroso or 102 av fuel then see what mpg you get. Guys the computer and sensors are set and i've tried that too and it dosen't buy you anything My 2cents

 

Depending on the octane and ethanol. Fuel mileage will vary about +\-1 mpg. Not significant. Where I live it’s cheapest to run 88 octane (e15) because it’s about 40 cents cheaper per gallon.

 

According to the manual, the truck can take 87 and above, and a TopTier brand is recommended.

https://www.toptiergas.com/fuel-stations/

 

The manual says it's important that ethanol stays below 15% (E15 or lower). The tundra is not designed to use FlexFuel.

Alcohol can react with and corrode Aluminum at high temperatures, and the engine is largely made of aluminum.
This is a technical report discussing it (not by Toyota)
https://www.diva-portal.org/smash/get/diva2:720728/FULLTEXT01.pdf

 

From: https://www.tundras.com/threads/what-grade-fuel-are-you-burning.15757/page-5#post-2398639

One of our past members is a Shell engineer. This is what he said:

"Hi, there is potentially more but more likely different detergents. It’s all about cost. My recommendation would be to buy and additive and not use the premium. You’re wasting your money as your engine is designed for regular. Premium is harder to combust, higher octane, harder to combust. When it does combust, bigger explosion=more power. That’s why avgas and stuff is 102-104 Octane, or somewhere around there. If you don’t want to buy and additive then the premium is ok but I wouldn’t do that too much. It’s extra strain on your engine and you may end up with more gunk on your cylinders since you can’t combust all of it. Feel free to post."

 

My 2024 Tundra was idling/running rough lately (8000 miles).
I decided to try premium gas (here at our altitude that is 91 octane).


My engine run much smoother, idles smoother and I have gained 3 mpg on three tanks now.