Octane use

Here's your manual - if you save it to your computer, you can search it and it's better than the printed one (and doesn't fill your tiny glovebox):
https://www.toyota.com/t3Portal/document/om-s/OM47A17U/pdf/OM47A17U.pdf

It's the USA Manual, I believe.

Also - OCTANE rating is measured differently in different countries - so you want USA responses (not Aussie ones which are different).

 

In California its the lowest grade unleaded available (87). There is no advantage in using the more expensive ones - you won't get better power or economy.

kevin

 

87 octane, unless you are over 4500 feet, then 85

 

Google:

Toyota techinfo

Likely the first result will be the right one. Click on "manuals" tab, fill in your car info and search. You'll find both owner's manual and the warranty/maintenance booklet available.

 

That’s unfortunate. I’d suggest buying a copy of the paper Owner’s Manual to keep in the car for reference. These are sold by Helm, Inc., as part number OM47A29U; the price is $32.95 each, plus shipping and tax.

 

I put 95oct into my Prius 4gen., No Problemos.

 

Finland uses RON octane, the US uses AKI octane, there is no direct conversion.

"Finland: 95 and 98 (RON), advertised as such, at almost all gas stations. Most cars run on 95, but 98 is available for vehicles that need higher octane fuel, or older models containing parts easily damaged by high ethanol content. Shell offers V-Power, advertised as "over 99 octane", instead of 98. In the beginning of 2011 95 RON was replaced by 95E10 containing 10% ethanol, and 98 RON by 98E5, containing 5% ethanol. ST1 also offers RE85 on some stations, which is 85% ethanol made from biodegradable waste (from which the advertised name "ReFuel" comes). RE85 is only suitable for flexifuel cars that can run on high-percentage ethanol" - Octane rating - Wikipedia

If lower octane fuel was available in Finland, it would be fine.

 

Well, I just refueled for the first time.

• The manual says "Select octane rating 87 (Research Octane Number 91) or higher. Use of unleaded gasoline with an octane rating lower than 87 may result in engine knocking. Persistent knocking can lead to engine damage."

• Wikipedia says, "in Canada, the United States, Brazil, and some other countries, the headline number is the average of the RON and the MON, called the Anti-Knock Index (AKI), and often written on pumps as (R+M)/2"
• So, I think the manual is saying I need MON >= 87, and RON >= 91. I sure don't want engine damage, and I don't mind pampering it because it's brand new, so I headed off to the gas station ready to purchase gas with at least a posted value of (87 + 91)/2 = 89. When I got there, the only choices were 85, 87, and 91! So, it seemed like 91 is the only option, and that's what I refueled with.
• But next, I read (above) JimboPalmer says "87 octane, unless you are over 4500 feet, then 85". I am at 5200', so now I am pretty thoroughly confused. I didn't see anything in the manual about different octane at altitude.

Help please...

 

69 or 666 or 13 or 99 or 3.14. I usually use 87 that is the cheapest most available. I tried something called 85, not the ethanol it was ok. anything over 87 is a waste of money. I find it weird how some cars can only recommend premium when a hybrid takes regular/cheap stuff. I live near Chicago, Illinois USA.

 

Also, you can google manuals and books.

 

The 87 number refers to the standard U.S. scale, so that is all you need. Any higher number is not pampering your car, it is just bleeding your wallet.

The RON number is for your travels outside the US or Canada.

Plenty of us buy 85 in the portions of the U.S. where it is sold, which are only at high altitudes that are a long drive (typically more than a tank's drive for shorter range cars of a generation ago) away from low altitudes. Old style traditional non-hybrids worked just fine with it in the thinner air up there, and we simply haven't heard of any modern 87-rated cars having a problem with it either. But with today's cars having a much longer fuel range, it is now theoretically possible to fill up with 85 octane and then drive far enough away from Colorado-Wyoming-Montana to reach some lower elevations where 87 is more advisable.

So if you are uncomfortable with that, then just stick with 87 octane while in the U.S. I haven't driven in Mexico or points south of there, so can't tell you what octane rating scale they use or what pump numbers are required there.

 

Thanks fuzzy1 for your thoughts. I never thought much about octane before, and had been using 85 in Colorado for 20 years. Just suddenly with all the crazy high-tech features on my new Prius, I have started to think twice about everything.

The manual is really unclear with the statement "Select octane rating 87 (Research Octane Number 91) or higher." Aiming to buy the minimum that meets this standard, I'm left with two possibilities:

• try to purchase gas with R=91, M=87, and (R+M)/2 = 89, but that doesn't exist in my area
• or, try to purchase gas with R=91, M=83, and (R+M)/2 = 87 which seems to be widely available, and just really hope that Toyota was not referring to "M" when they said 87 is the minimum!

Anyway I guess I have another 450 miles to think about this until next time...

 

It's just different measurements - like US Gallons aren't the same as the rest of the world. Similarly, what is called RON 91 for most of the world is roughly equivalent to your 87. US87 will be fine.

My copy of the 2016 USA Manual says:


Is there any indication on the fuel fill flap?

 

Here is the EPA statement:
Selecting the Right Octane Fuel

 

Most places, most stations, if you use the regular, you can't go wrong.

 

If you watch the tanker refuel the gas station, the guy uses only 1 hose to pump the gas down into the tanks. And if you follow him, not recommended, he goes to all the expensive stations as well as the cheap stations.

 

Ok, wait a sec: you're saying there is absolutely no difference between the 3 (sometimes 4) octane pumps? I can't buy that. How about this:

There might be 2 underground tanks, at a 3 octane station, and the middle octane is a blend of the two. That's highly plausible, I suspect what Shell does up here.