Jskennedy, I am sure people have been responding to your posts in an attempt to help you. No one wants to see someone make a bad decision that could cost them later. You paid a lot of money for a car that you might as well benefit from it's peak performance by using the correct fuel, instead of doing what could cause you problems later. Recommendations by the manufacturer are the minimum requirements to keep your vehicle performing properly. There is no conspiracy involved.

 

i agree, i believe the posts in this thread have been sincere

& i appreciate everyone's input

i'm unsure if you're referring to conspiracy among posters or among manufacturers

in either case, i do not believe, nor have i suggested there is any conspiracy taking place

thanks

shane

 

As long as you're not wearing a foil hat, then your conspiracy views are within reason.
From an engineering standpoint, higher octane fuels are recommended for a variety of reasons, most notably the compression ratio of the engine/cylinders. Higher compression yields better performance, in general, but also needs higher octane to take advantage of that potential performance capability. Yes, you can be cheap and use 87 octane, and the computer will retard the timing to prevent knock. THis is all done by the black box..., personally have never seen an end-user monitor to see that stuff. Timing light wouldn't really work either, since it would have to be done under load. Not likely to hurt anything by using 87 octane, unless (for various factors including quality of gasoline, temperature, carbon fouling etc) you actually hear knocking, which means that the box can't keep up with the other factors and compensate. Higher octane fuels do have more detergents in them, so I have learned my lesson and use top tier premium as often as possible. Alternatively, because my work truck usually gets fuel elsewhere, I use lower octane fuel and use Techron fuel system cleaner every few thousand miles to keep things clean. I just choose to baby the Lexus, because my spouse drives it mainly and, well, it's a Lexus. OK, end of diatribe. Hopefully this summarizes what others have basically said, but in a more verbose forum. Unfortunately, this message will not self destruct.

 

Yes you can run your engine at below performance level and have constant retartation of timing due to slight knocking that you will not hear or feel. Its your engine, you are free to run at it anyway you want.

 

this is a theory of mine, i've seen so many check engine light flashing due to engine cylinders misfiring, especially on the older gen Rx300. Almost every time, it's the ignition coil pack gone bad.

I noticed there were times when the gas prices rocketed, i had about 3 or 4 customers came in with this condition, and i asked each of them which fuel type do they use, if i recall correctly, almost if not all the answers were cheap costco gas because they didn't know they had to use premium gas.

bottom line is this, Lexus engineers have designed these motors to run on high octane fuel and have tested using such fuel. So for someone to cheap out on gas and go against the recommendation, assumes the risk of running into unexpected/premature engine component failure.

 

Although there is a differance between premium and regular gas, however there is no difference between let say Cstco Premium and Shell premium, specially in US. In fact in many places one company's distributer would supply all the gas stations in the area. I used to work for Texaco in US back in the days and our #1 distributer in NorthEast used to be Sunoco. High Octane gasoline is the same everywhere you go, stuff like V-power is just advertisment. The reason Costco gas is cheap, because it buy's in buld in advance and does absolutly NO advertisment!

 

actually there are differences albeit small--using KISS--gasoline is pushed thru pipelines and sent to local terminal. Sorted into tanks by the octane. The same tank fills trucks regardless of which company EXCEPT the additives for each company are added at the time the tanker truck is filled. The additives are probably just slightly different if that but called something else--ie--mobil, BP and Shell are different due to their specific additives.

Now-an old discussion--who has "pure" gasoline--ie no ethanol?

 

The additives are different between the diff. brands, that is why the major car companies came up with a list of the top teir gas brand that they recommand the owners to use. Some German car will run much better on Shell's nitrogenated gas, and the Shell V-power is one of the best gas on the market when it comes to cleaning additive. If you are in the South, Chervon is the way to go.

 

Hal
A little while ago while I was filling up at my local Shell, I noticed a decal on the pump that going on memory said "Regular fuel may have 10% ethanol". Of course presuming can be dangerous but wouldn't you take that to mean that if you were to purchase the mid-grade or premium (I did) that it would be pure Non-Ethanol gas? I didn't have time to go inside and ask but even if I did I'm not sure I could understand the station operator. He's from India and nice enough but his accent is so thick he's hard to understand.

Your take on that phrase ???

 

Ethanol is used for an oxygenating agent to reduce carbon monoxide in a combusion engine, it replace MTBE which was found to contaminated groundwater. The 10% ethanol gas is found in regular, mid grade and high octane. In most populated areas, a 10% ethanol blend is require by the EPA.

 

Hal
I just got off the phone with Shell and went all the way to a senior 'specialist' with gas.

Bottom line from her is if the pump has a decal indicating that regular 'may' have ethanol we should assume it has it. If the other two grades did not have the decal, we should assume that they do not have ethanol.

IMHO, that's great news for us and it's not from someone that doesn't know what they're talking about.

Now I'm in North Georgia. If it wouldn't be too much trouble could you and others check the pumps for decals when you buy gas in your various locals and post here?

I also have a list here of the Top Tier retailers in the U.S. It's alarming to me of how many gas stations are not on this list. http://www.toptiergas.com/retailers.html

 

I think all companies/grades are required to add the ethanol. It is for emissions control.

 

Jim,

My Shell dealer has the sticker on the pump saying the gas may contain 10% ethanol but it is not octane specific (i.e. near the numbers). Nice disclaimer

 

Exactly, why would the EPA require 10% ethanol in one grade and not another, that would not make sense, its not octane specific but are area specific.

 

To ease our dependence on foreign oil and to replace MTBE which is bad stuff for the environment, the gasoline industry started putting ethanol in gasoline. I don't think this is a mandaatory requirement yet since some gasoline station are selling gasoline without ethanol. But a majority is and there is no distinction between grades.

There are countries like Brazil that gives the option to pump pure ethanol. Some of the cars over there are specifically design to run on it. Corn is still cheaper than gasoline but becoming expensive. I dont mind running on higher than 10% ethanol just to decrease our dependency on foreign crude oil.