What octane do you run?

[Bph555]

Fuel won't matter at all.
I Put 40,000 miles on my 100 all through Central and South America, sometimes straining "gas" through at tshirt.
We bought gas from the most run down,out-of-the way, fuel stations imaginable.
We filled up near Pisco, Peru (sea level) and immediately climbed to 16,000 feet above sea level, with the truck totally overloaded. This scenario happened over and over again, over countless full tanks, along with endless full throttle,uphill, assaults on slower moving traffic.
The 100 never skipped a beat and runs perfect to this day!

 

[dadswithcars]

So what happened that the 02+ vehicles are recommended for 87+, whereas older ones (my '99) are only 91+?

I generally appreciate the "built for the world" idea, but
1. Most of the world isn't using the 4.7 V8 Gas
and more importantly
2. I want to use the "Recommended" just assuming that was the design intent for the longevity of the engine.

Owners Manual recommendations:
View attachment 1324114
(It would be kind of silly for Toyota to make one of their "World Traveler" flagship vehicles unable to retard the timing enough to operate on 87+ fuel.)

Additional annual costs associated with "premium" (assuming 13MPG):
View attachment 1324108

​

 

[brianrride]

Fuel won't matter at all.
I Put 40,000 miles on my 100 all through Central and South America, sometimes straining "gas" through at tshirt.
We bought gas from the most run down,out-of-the way, fuel stations imaginable.
We filled up near Pisco, Peru (sea level) and immediately climbed to 16,000 feet above sea level, with the truck totally overloaded. This scenario happened over and over again, over countless full tanks, along with endless full throttle,uphill, assaults on slower moving traffic.
The 100 never skipped a beat and runs perfect to this day!

Love it. Great little story man.

 

[JayM]

I believe Toyota has recommended the higher octane to keep the mpg as high as possible for cafe standard testing and emmisions. You can run more aggressive timing curve and improve performance and efficiency with the higher octane. Is it that noticable? I think a little. If you look at the numbers from Toyota's perspective trying to achieve a certain goal for cafe I think it makes a huge difference. I think if they ran higher octane to achieve cafe goals then they must recommend you run that fuel.

 

[Nottajeep]

I run 87 ethanol free in the 100 and premium ethanol in the 55 with 2UZ supercharger

 

[Live to Ski]

Table shows "recommended". That is not a requirement.

I guess one needs to ask "why recommended": my thinking it is for toyota's benefit regarding warranty/pollution or mileage issues (as in trying to match gov't mileage mandates). However, I am speaking out of total ignorance on this.

 

[Nottajeep]

My 3UZ in the LS 430 gets premium every fill up. The Lexus manual states to minimize the regular as much as possible due to engine related issues. Doesn't get any more specific. Model is 2006 LS

 

[jLB]

So what happened that the 02+ vehicles are recommended for 87+, whereas older ones (my '99) are only 91+?

Probably no mechanical/programming change, just the individual or group that wrote (or translated) that portion of the manual.

I generally appreciate the "built for the world" idea, but
1. Most of the world isn't using the 4.7 V8 Gas

It may not be the most popular choice (outside the US), but if this source is correct, it seems widely available in markets outside the US:
Toyota Land Cruiser - Wikipedia

2. I want to use the "Recommended" just assuming that was the design intent for the longevity of the engine.

It probably won't make one lick of difference, as long as it has 87 octane or more.

 

[blklnamru]

I've been running 87 for the last few tanks... and my butt dyno tells me response time is weak, requires more throttle for downshifts during hill climbs. However, as I drive east this December and go through countless back to back tanks I am going to see if there is a big difference in MPG's I get from 87 vs 91 (the highest available in most SoCal locations).

So far 91 has yielded the best results per Fuelly, however I'm back to 87 for the time being since not towing or lugging around weight.

 

[JayM]

I've been running 87 for the last few tanks... and my butt dyno tells me response =time is weak, requires more throttle for downshifts during hill climbs. However, as I drive east this December and go through countless back to back tanks I am going to see if there is a big difference in MPG's I get from 87 vs 91 (the highest available in most SoCal locations).

So far 91 has yielded the best results per Fuelly, however I'm back to 87 for the time being since not towing or lugging around weight.

I would not be surprised to see a mpg drop. Less ignition timing advance with the 87 octane = more pedal to climb, downshift, and such will effect it for sure. A test running through the same mountain passes would be interesting. Probably not a huge difference in mpg in the end. I still like the way it feels running 91+.

 

[KYLandy]

I have owned my 06 LC100 a little over a month and I have been running 87 octane in it and I have noticed it has a hesitation in the throttle when I goose the throttle. I am also dealing with DTC codes P0420 and P0430 so I decided to put 91 in it tonight and drove it for about 20 minutes. During that time, the ECU ran the Catalyst Efficiency monitor and it passed! It just barely passed but it did pass and it has not done that while running 87. I am interested to see if the codes come back again on this tank of fuel. Granted, the cats are likely going bad based on my testing but I wonder if there is a correlation between 87 octane and the life of the cats. This LC was a NY vehicle all of its life so I am curious about what fuel was used in it. I bought it from a dealer so I did not have the opportunity to ask the PO. It is too early to know if the 91 octane is going to keep the DTC's from returning, but I have usually seen the DTC's return after driving only 25 miles or so. I'll drive it more than that tomorrow and report back here. I'll connect it to Techstream and see if the codes are pending when I get back. It takes 2 driving cycles with a failed test to set the DTCs so I will make sure I stop and start again to get the 2 drive cycle minimum completed.

 

[LXPearl]

We ran 87 in the 01 LC almost exclusively except some of the times we were very heavily loaded and in hilly terrain. Then we would run 89 or 91+. I noticed no change in mileage between tanks. Mileage consistently improved in higher altitudes (>4000 ft) regardless of the fuel grade.

When we got the 01 LX, the dealership told my wife it should use premium, even though it was no longer "required" in 01. So it got premium. I did some comparison with 87. Initially I could not tell any significant difference. But cruise control on rolling terrain was the first note of a difference. Driving the same hwy on 87 required more frequent downshifts by the cruise control on the incline portions; whereas 93 had notably fewer downshifts. This led to noticing other subtle differences in acceleration pedal responsiveness and shifting. Gas mileage difference was essentially negligible, with the LX getting slightly better than we did with the LC (LX= 14.3, LC = 14.0 overall).

Reading Toyota literature, all Toyota engines are made to adjust to the fuel in them and the engine controls will adapt. The adjustment is quick to a lower octane, but slow in recovering to tanks of higher octane fuel. Typically, it will take multiple fills of 93 to return to full efficiency. Comparing the same engine specs with Lexus showing 91 octane and Toyota showing 87 octane shows HP to be adversely impacted by <10 HP.

The cruise control comparison on the same stretches of hwy became a good test for other Toyota vehicles; and the frequency of downshifts on inclines was a factor, regardless of whether the vehicle was rated for regular or premium. Driveability and responsiveness in heavy traffic is also a notable distinguishing observation; again regardless of the fuel designation. Lexus is designed for smooth pedal response and minimal downshifts on the highways - for this 91 octane fills the bill. It will run on 87, but the pedal responsiveness will be a bit more jerky and downshifts on the highway more frequent. Neither octane resulted in engine knocking in any of our Toyota/Lexus vehicles; it is really about engine control and drive train timing. I usually would use 3 tanks of 93 before making the comparisons. So when heavily loaded, or in demanding situations, 91+ has a notable benefit. If you want a smoother, more responsive engine, then 91+ will have a benefit for essentially any Toyota engine in the past 20 years. If you want specifics, you can check the Toyota Training Course materials on the TIS site that cover engine controls. The takeaway for me was that Toyota designed their engines to run on a wide range of fuel octanes, so even those designed for 87 will respond with enhanced performance charateristics when using 93. So it is not as simple as Consumer Reports may lead one to think, the modern engine controls optimize performance of an engine based on the fuel it is using - thus affecting horsepower, torque, efficiency, and mileage.

Now that I am used to how our Lexus and Toyota vehicles drive with 93, the difference is noticeable when we use 87; even in vehicles designating 87. We only use "Top Tier" rated fuel.

 

[KYLandy]

Well, The 91 octane did not keep the P0420 and P0430 codes from returning. The light came on this morning on the way to work. I haven't pulled the codes to confirm, but I'm sure that is what it is. I was able to drive 78 miles before the light came on this time so it did delay the light for a little bit. It's so weird how the cats will pass the efficiency test sometimes and fail on others. Seems like an intermittent problem to me. Anyhoo, I ordered some NGK Laser IR spark plugs and I'll be changing plugs sometime this week.

On another note, I took a photo of my Emissions Label and it confirms what I have read and thought to be be true. My 06 MY conforms to California and EPA emissions regulations.

 

[f5driver]

The difference between 87 and 91 is 10 miles more per tank. Negligible difference in perceived performance. 91 doesn't seem worth the 30-40% price increase over 87

 

[Greenbean]

Owners Manual recommendations:
View attachment 1324114

OK so what did Toyota change in 2002?

Was it the engine change? I am struggling this morning, lol...

 

[graveling]

I just bought a 99 LC but have driven a 00 tundra with the same engine for 15 years. Not once in those 277k have I put premium in the tundra. I'm genuinely interested if someone know the difference between then engines and why the LC need premium since I've put in both prem and reg in the LC and noticed no difference in both highway and city driving.

 

[jLB]

OK so what did Toyota change in 2002?

Was it the engine change? I am struggling this morning, lol...

Probably not a darn thing, other than the technical writer/translator.

 

[Malleus]

IIRC, Toyota changed the octane recommendations after the CAFE standards were revised, but that was 20 years ago and I may be off by a few years. More important to the LC/470 engines is the total absence of alcohol in the engine. Although you may not have noticed problems puting Jimmy Carter's gasohol in your engine, the seals weren't designed for it. I have never found non-ethanol gas in less than 91 octane. It's as expensive (if not more) than 93 octane here, but IMHO, it's worth every penny. I do not put ethanol "enhanced" fuels in any of my engines, unless I absolutely have to, and I run it out and flush the tank as soon as possible.

 

[Exiled]

I've run regular unleaded on all three of my 100s since I bought them with never an issue. These things were built to run on crap gas all over the world, US-quality regular unleaded is like av gas in other markets!

 

[SlowBuild]

IIRC, Toyota changed the octane recommendations after the CAFE standards were revised, but that was 20 years ago and I may be off by a few years. More important to the LC/470 engines is the total absence of alcohol in the engine. Although you may not have noticed problems puting Jimmy Carter's gasohol in your engine, the seals weren't designed for it. I have never found non-ethanol gas in less than 91 octane. It's as expensive (if not more) than 93 octane here, but IMHO, it's worth every penny. I do not put ethanol "enhanced" fuels in any of my engines, unless I absolutely have to, and I run it out and flush the tank as soon as possible.

I ran premium in my 06LX for a few years with the same thinking (I can’t get e free anywhere near where I live), figuring it was probably better fuel.

Following a tip from the boiling fuel thread though, I’ve switched to regular with no noticeable difference in performance the past 10k mikes or so. The idea is that ethanol is added as a cheap way to boost octane. So, lower octane fuel is likely to have less ethanol actually added. Cheaper and less corn. Win win.

Or maybe it’s bs