Grade Of Gas Used, 87 or 91? Options

[specialeffects]

Hi,
I woulke to start a thread to know what grade of gasoline you use and why? If that grade gives u the best mileage.

I used 87 and got 14 mpg , with 91 I get 18.5 mpg

[mann777]

I use 91, but all also depends on your ride, the usuage of A/c, Currently I get around 17mpg.

[The G Man]

Hi,
I woulke to start a thread to know what grade of gasoline you use and why? If that grade gives u the best mileage.

I used 87 and got 14 mpg , with 91 I get 18.5 mpg

There is no way you can get that big of a difference in mileage lol.

[Spirit of 1776]

If your GX is 2005 or newer use 91 Octane. 2003 & 2004 models are fine with 87 Octane.

Also, altitude can also play a factor. If you live above 6,000 feet, 87 Octane will actually be nearly identical to 91 Octane in terms of performance. So high-altitude residents could use 87 Octance regardless of model year.

[lazybummm]

If your GX is 2005 or newer use 91 Octane. 2003 & 2004 models are fine with 87 Octane.

Also, altitude can also play a factor. If you live above 6,000 feet, 87 Octane will actually be nearly identical to 91 Octane in terms of performance. So high-altitude residents could use 87 Octance regardless of model year.

Spirit... is right on....

This is true. Altitude can have a radical effect on fuel consumption. The ECU controlled FI systems in today's engines have excellent compensation built in, like High Altitude compensators that advance ignition timing, etc, but it would not be unusual to see a 3 to 4 HP drop for every 1,000 feet in elevation increase.

It's also true at high elevations, typically higher octane fuel will not compensate for the lack of Oxygen, and actually may "burn" better than 91 octane.

been pumping 87 in a 2004 gx for years, gets about 16.8-17mpg combined...up to 19 for mostly highway

[mann777]

One point on saving fuel that is never mentioned is using the brake as little as possible. The brake converts kinetic energy into heat energy which is then lost.we likely feel desperate whenever we heard 'bout higher gas prices that is ravaging us these days.. so some are thinking of necessary measures to address this problem such as looking for ways to improve gas mileage. Hypermiling techniques would be a great idea.
Look, I have read a lot of the replies and the article and have also been doing extensive research on the web after I came into contact with a local man in my area who showed me this amazing yet simple device he made in his garage. I have read up on the history of Gasoline vs California and the attempt made by California to force the Oil Companies to formulate their Gas to burn more completely (which they did for a short time which resulted in lower profits due to MGP drastically improved)which was thrown away at the nearest opportunity. Thing is, and has been proven, only 20% on average of the fuel that goes into the combustion chamber burns, and what is left over comes out of the exhaust valves on the cylinder heads. This from what I have read is due Gasoline molecules being very close together and not being able to burn more completely. To be able to improve this would mean you would have to find a way to space the molecules apart a bit, which was accomplished for a short time by the oil companies but found a way to convince the people that the additive was harmful (probably by design knowing them). So we are back to the inefficient formula again. But if there was a way to increase MPG and lower emissions would it be implemented? The problem is the economy we live in is highly dependant on "Oil" revenues, and anything that would rapidly effect those revenues could make the Economy collapse and in effect make the US bankrupt or worse. It is not surprising to me to see the political element wanting to resist these changes and want to cover up something as significant as electrolysis devices that could possibly in short order replace fossil fuels. But I think they won’t be able to keep it under wraps too much longer. Too many people are realizing how simple it is to turn water into Hydrogen and Oxygen. And if Gas is replaced by Water, how could they possibly tax that? Meter on your Garden Hose? I don’t wanna hear the negative bull crap about how inefficient it is and takes way more effort to break down than it is worth

[smlotr]

Hi,
I woulke to start a thread to know what grade of gasoline you use and why? If that grade gives u the best mileage.

I used 87 and got 14 mpg , with 91 I get 18.5 mpg

There is no way you can get that big of a difference in mileage lol.

It does sound like a big leap. But if the factory specs call for 91, then it's possible you could see a drop in mileage using 87.

In order to get a good comparison test, you'd have to carefully monitor the factors that can change A/F, gasoline/engine performance and use more than just a couple of tanks of fuel....

Was the gas used from the same brand and gas station?
Was the test route driven exactly the same with the same MPH under the same driving conditions?
Was the ambient air temp, RH, and barometric pressure the same?
Did you measure and start with the exact same amount of gas in your tank?

believe it or not proper tire inflation does increase mpg...

[specialeffects]

I am now getting 20 in City with Costco Premium gas in Phoenix for over a month, yes in stop an go conditions not highway.

Hi,
I woulke to start a thread to know what grade of gasoline you use and why? If that grade gives u the best mileage.

I used 87 and got 14 mpg , with 91 I get 18.5 mpg

There is no way you can get that big of a difference in mileage lol.

It does sound like a big leap. But if the factory specs call for 91, then it's possible you could see a drop in mileage using 87.

In order to get a good comparison test, you'd have to carefully monitor the factors that can change A/F, gasoline/engine performance and use more than just a couple of tanks of fuel....

Was the gas used from the same brand and gas station?
Was the test route driven exactly the same with the same MPH under the same driving conditions?
Was the ambient air temp, RH, and barometric pressure the same?
Did you measure and start with the exact same amount of gas in your tank?

believe it or not proper tire inflation does increase mpg...

[BobsGX470]

[quote name='specialeffects' date='Mar 26 2009, 11:43 PM' post='363770']
I am now getting 20 in City with Costco Premium gas in Phoenix for over a month, yes in stop an go conditions not highway.

I hope you are not going by the on board mpg computer. Those things are always optimistic by 2-5 mpg. Figure it out the old fashioned way with pen and paper. Or for those that forgot how to divide, use a calculator.

[JimsGX]

I use Shell 93 Octane in my 08 GX and 91 LS400... Both cars run better on it than other brands of fuel I've used in the past. Shell puts a lot of detergent in the fuel. I get 19 on the highway and 16 or so in the city.

Top Tier Fuel Companies

[Wacko999]

I use 85 octane due to the the elevation here in Denver with no problems.

[denslexusgx470]

91 is always recommended... but as far as required fuel, the non vvt-i engines (03-04) do NOT require 91 and may run on 87 but the 05-present have the VVt-i engine that require 91

[Harley Rider]

We've been driving our 2005 GX between S-E Michigan and DC area every other month or so for the past 3 years. We've tried 87, 89, 91 (sometimes mixing 89 and 93 - 91 is hard to find), as well as straight 93. Using 93 costs around 10% more than 87, but regularly gets us 10-12% better mileage - same trip, same driving habits - so I have been using 93 (or an 89-93 blend when I have the time). Averaging around 17 in my 34 mile daily commute and 19-plus on our DC trips (as high as 22mpg on one trip with a tail wind) - staying within Ohio's posted speed limits. All mileages from calculation, NOT from the trip computer, which always registers 1.2 to 1.4 mpg higher than calculated.

[nc211]

My 05' 4runner has the exact same engine as the GX (4.7 liter V8 vvti). I have only put premium in it once, and have never had a single problem. During our migration from NC to Chicago last February (845 miles) though West Virginia mountains and the flat lands of Ohio and Indiana. I kept all receipts of all fuel bills, and set the trip odemeter at 0' as we were pulling out of the driveway. We were loaded down too with stuff, 3 cats, and a fish in the cup holder. Average mileage for the trip on regular gas? 22.3mpgs. That is on the old fashioned way of calculation too, not the car's computer read out. I have never had a "ping" problem, rough idle, or squat. So I am hesitant to spend the extra $$ on premium.

[Dr.Gee]

I use the high test stuff and get about an extra 50 miles per tank.