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Whats with the pricing games of these gas companies. Why is 87 octane 3.45 a gallon (in my area), & then 89 octane which I use is .25 cents more a gallon on average. What happened to the traditional .10 cents more a gallon from 87 to 89, & .10 cents more from 89 to 92?
Is this there way of switching us to hybrid cars, or cars that run on 87 octane gas?
I need gas in 2 days, and might be putting 87 octane in for the first time if things don't change. Havn't decide yet. Not sure if its worth 5.00 more dollars for an 89 octane fill up. (I've owned this car for 1 year, & have always used 89 octane.)
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2004 Maxima 3.5 SE (Built Mar. 04)
Majestic Blue/5AT
Leather/Moonroof/Bose
33,000 miles
(Purchased Aug. 2007 with 27,700 miles)
Previous Vehicle-1994 Firebird Formula (5.7/LT1)
(Sold Aug. 2007 with 104,000 miles)
The oil industry for years had a recommended 10 cent per gallon price spread between regular and mid-grade and the same 10 cent per gallon spread between mid-grade and premium. But times have changed. The refining costs for making higher octane have increased and the wholesale price for the higher octane gasolines have also increased. (When oil companies sell product to other oil companies they charge more than 10 cents for the higher octane -- more nearly 15 cents in some cases.)
Most oil companies no longer "recommend" that their dealers use this 10 cent spread -- because many companies in many different locations charge the dealer more than this spread for the higher octane fuels. So the dealer makes the final decision on the retail price -- and more dealers are opting to charge more for the higher octane gasolines.
Given these cost pressures on dealers, I suspect that the number of stations continuing to use the 10 cent spread will decline and eventually dissapear. Gas dealers can't use the tricks used in the grocery business -- making the package slightly smaller and charging the same price as had previously been charged for a larger package.
There is no easy solution for this problem -- but you could consider running regular gasoline in your Max. I have done so for most of its 76 K mile life and have had no problems. But then I very rarely call for WOT (wide open throttle). If you do that frequently, stick to premium.
I've been finding something strange, For the last 2 fill ups I've been using the Ultra 94 Octane, and I'm getting insane gas mileage. So although this premium gas costs more, I need to calculate if in fact it's cheaper for MPG.
I'm not sure the exact number, i'll try to do the calculation - but I switched back to regular and it seems to be guzzling again. It's a brand new O2 sensor, so I wonder if the 94 octane causes the O2 sensor to operate differently.
I look at it like this. When 87 cost $1.00 there was a $0.10 difference between octanes.
seeing that 87 gas is now $3.00 it's awesome that some still charge $0.10-0.20 diffenence between octanes.
I have been paying only $0.30 more for 93 as opposed to 87 since i remember prices soaring. that is only 10% more. When 87 was $1.00 and 93 was $1.20-1.30 that was a 20-30% difference.
At my local Mobil prices were 3.09 for 87, 3.35 for 89, and 3.65 for 93, then the Shell 2 miles down was 2.92 for 87, 3.03 for 89, and 3.17 for 93. Odd the way the Mobil decided to price their gas, but I clearly opted for the Vpower.
__________________ 1999 Super Black SE 5MT '00VI|VAFC-II|Fed Spec Conversion|Cattman Y|Budget B|HKS Rear Section|Stillen Hi-Flow Intake
OBX STS|18" Mille Miglia Evo 5s|Stillen FSTB|Progress RSB|Intrax Springs|KYB AGX Struts|AE Pedals+350Z Dead Pedal
Escort Passport 8500 Hardwired|Red/Clear Tails|Clear Bumper Lights|35%/25% Tint|Nismo Shift Knob|I30 Leather E-Brake+Autodim Mirror
Exedy Stage II Clutch|I30 VLSD Transmission
In my area the diff is still on 10 cents or so, but supposing that changes to 25cents per grade level, then I might not use premium anymore. Should that be the case, what would be the best way of weaning the car off premium? Slowly introduce 89 octane w/ premium and then gradually all 89 octane and then keep stepping it down so to speak so the knock sensor and timing can adjust accordingly? I am concerned about damage by just dumping in 87oct shld this huge price thing catch on in my area.
Based on reading my 2004 Owners' Manual, the 2004 should have no problem with 87 Octane gasoline starting on the next fill-up. My only suggestion if you go to 87 Octane -- don't call for WOT acceleration. That is asking for maximum performance -- which Nissan says needs 91 Octane. Otherwise, you should have no problems with 87.
My max is a 2000. When I first got it at 55K miles on it I used 87oct and it knocked and then immediately learned of its "need" for premium and began using it right away and it runs better on it. But if prices change a lot then I may try to reduce oct to save $$ but don't want to damage the car, either.
So if I just avoid WOT then I'll be ok? I'm not so sure my car likes 87oct since it knocked w/ it before...??
My max is a 2000. When I first got it at 55K miles on it I used 87oct and it knocked and then immediately learned of its "need" for premium and began using it right away and it runs better on it. But if prices change a lot then I may try to reduce oct to save $$ but don't want to damage the car, either.
So if I just avoid WOT then I'll be ok? I'm not so sure my car likes 87oct since it knocked w/ it before...??
It is likely that this Max had engine deposits when you bought it -- thus the knocking on 87 octane. My suggestion is to do a fuel system clean-up on your Max. This should eliminate the deopsits that are very likely causing your engine to need premium gasoline.
I prefer Techron Fuel System cleaner. You likely have a 20 gallon fuel tank. You will need a bottle of Techron that works with 20 gallons of gasoline to clean your fuel system. Put the Techron in your fuel tank and then add gasoline on top to help mix the Techron with the gasoline. You should do this burning premium to prevent knocking until the system has been cleaned. You should run this tank of gasoline and Techron mixture down until the fuel warning light comes on (1/8 of a tank remaining) -- before putting any more gasoline in your fuel tank.
Deposits inside of your engine do three things that increase the octane requirement for that engine. 1) Deposits occupy space that should be filled with an air-fuel mixture, thus effectively increasing the compression ratio of your engine. 2) Deposits tend to glow while the engine is running which can cause lower octane fuel to pre-ignite and cause knocking. 3) Deposits in the engine reduce the ability of the inside of the engine to remain relatively cool. The higher temps caused by these deposits make the deposits glow and also keep the rest of the engine hotter than it would run without the deposits. The higher temps in the engine increase that engine's octrane requirement. Removing the deposits removes all of these problems and reduces the octane requirement of your engine back to what it was before the deposits formed in the engine. My memory is that your VQ engine has a 10 to 1 compression ratio, and my VQ has a 10.3 to 1 compression ration -- and mine runs fine on regular gasoline.
Good luck and let us know if this works for you.
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Last edited by SilverMax_04; 10-16-2008 at 12:03 PM.
Thanks for the lengthy info! I was not aware of those items. However, I have used Chev Techron a few times since I bought it at 55K miles 4 yrs ago. I believe it did smooth the idle (which is great) and I haven't tried the 87octane in yrs since I first switched to premium when I bought it. I just kept on w/ premium even though I have used the cleaner prob 4-5 times. I will try the 89oct on this next fillup and see how it responds. Many believe the premium does provide better mileage and if that is true then 10cents per gallon is worth the extra mileage, but if I dont need premium and it jumps to 25cents extra to get it than it will be good to know that it's not necessary. WOT performance is not necessary since I dont beat on it and once in a while I'll open it up to help in burning off any deposits, but I dont put it all the way to the floor. I'll try the 89 and see what happens and then step down to the 87oct.
Mich,
I don't expect you will see any difference in gas mileage by going to a lower octane. That is because I don't expect that your fuel system will detect knocking and retard the spark -- particularly with 89 octane mid-grade and you not calling for WOT. Even with 87 octane regular I doubt if there will be any difference.
Here at 6,000 feet elevation I burn 85 octane regular in my 04 Max. Because my Max does not have a turbo-charger, this 85 octane gasoline acts like 91 octane gasoline at sea level. When I go east I burn 87 octane, and see no noticable difference in gas mileage. There are so many factors -- other than octane -- that cause changes in gas mileage, that it is hard to determine why you get different mileage between different tanks of gasoline. My experience on highway gas mileage is that wind speed and direction is one of the most important factors. I have gotten almost 31 MPG driving 75 MPH when I had a tail wind (that helped push my Max down the highway). Then when I face a head wind, the highway mileage falls to 25-26 MPG. These are big effects on gas mileage, and much more important (IMHO) than differences in gasoline octane.
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