Lavrishevo

iTrader: (1)

I'm about to drive from NJ to GA on Monday evening. I'll compare beetween 93 and 87 for ****z and giggles. Lately I have been running 87 as there is about a $11 per tank difference and my 430 seems to run just as good on 87 as it does on 93.

Tom57

Welcome to the "dark side" of the octane debate! I've been using 87 octane for over 20 years and literally hundreds of thousands of miles on LS's. No issues, no regrets. Safe travels.

beer

then go buy a cheap car that can take 87. I would NEVER put anything less than premium in a ls. I wouldn't even bother with arco premium; only real premium.


so, I have been told that 91 actually burns 'slower' than 87. If you don't do jack rabbit starts and actually drive decent, you can get better fuel economy and possibly save money buying 91 over 87 (due to it 'burning slower'). I originally heard about it on a local forum about a guy who was testing it out in his ae86. he found that he did in fact save money buying 91 and driving conservatively.


I have a 94 yota pickup that I only put 91 in. It seems to like it (duh), and I get almost 30mpg. Sorry if this has already been discussed, I sorta just quoted the OP. with that said, I have no references, so take it as a suggestion. I can confirm that I do personally get better mileage in my truck w/ 91 though.

Stu

I have used 91 octane for the past 5 years I have owned my LS. I have run a couple of tanks of 87 when I went for a long highway drive and had no issues. I use 91 because the car drives better in stop and go city driving AND it gets better gas mileage when I use it. I drive very smoothly except when merging onto the highway.

Lavrishevo

iTrader: (1)

If the car can adjust timing to prevent pinging or knock then running 87 vs 93 only means slightly less power and maybe tad bit less mileage. It's been pretty much proven that 87 does not negatively affect the 400, 430, or 460.

Bocatrip

I have used only premium since purchase 5 years ago.Tried 89 for 2 tankfuls and mileage ( as well as noticeable drop in acceleration) dropped 3mpg. End of subject. Premium only. We have a luxury automobile not a Toyota Yaris. I'll be rich a day later!

Lavrishevo

iTrader: (1)

I did not notice that much drop in mileage personally. Maybe 1 or 2 mpg. Even at 3 mpg over lets say 16 gallons this equals 48 miles for an extra $11. It's a waste of money.

warminwisc

I run midgrade 89 NO ETHANOL in my LS seems to run fine. Premo used to be 20 cents now 80 cents difference. If regular is safe by Tom57 standards and many miles it is good for me though. Never heard of to many cat problems in all these years here. This OK SW?

tradosauru

I took a 650 mile round trip this weekend. I started with a full tank of 89 octane (downhill) and on the way back used 93 octane (uphill).


It might be a invalid perception but it seem like the car didn't run as well on 89 octane as it did with 93 octane. Also I felt that 87 octane (no ethanol) ran better than 89 octane.


The MPG going mostly down hill with 4 adults and luggage was 23.6 mpg. The MPG going back (uphill) was about the same.

zapola6

In Colorado we have 85 / 87 / 91. I bought my 01 LS just over 3 years ago, since then I have put almost 100K on it. Current odometer 213,000+.

I run 85, have no issues and drive almost 100 miles a day. I can say to this point I have not seen any negative results from running 85. Colorado also runs winter & summer blended fuels with 10% ethanol. I have played with running higher octane with no noticeable improvement in mileage or performance. Now if this were a new car I would have different thoughts, but in a 14/15 year old car????? I do run 91 in the wife's 2014 Audi A7 Premium.

To this point, in the last 100,000 miles the only failure I have had was a # 3 coil pack that went bad. I have done all other related preventive maintenance. I did pull a plug the other day for giggles, around 90K on the plugs, it looked fine for a plug with 90K.... I'm averaging 22.7 MPG and 48 MPH over the past couple of years.

The only time that I do see an improvement in MPG is when I get out of Colorado and can buy some real gas. That improvement is marginal, up maybe 1.0 MPG

We will see if there is any impact in the next 100K i guess......

I don't drive it like I stole it, at times I have been known to drive it like it's a rental....

tradosauru

I've heard that cars operating in higher elevations can get away with lower octane fuel because the thinner air tends to retard detonation.

I'm not sure I would be brave enough to put 85 octane in any of my cars. ;o)

ltd76gold

Rode with premium to New Orleans. 25.59 mpg

Reverse trip to South Padre with regular.
24.08.

Impressions.

Premium....outstanding acceleration
Regular... Pretty good.

Worth the 30cent "premium" average price? Financially.... No

Seat of the pants..... Absolutely,,!
😈

​​​​​​​Doug k

jayclapp

Difference might be due to change in elevation. New Orleans at sea level. Texas, likely higher elevation. Downhill to New Orleans? Uphill to home?

ltd76gold

About zero in elevation change.. Sea level to sea level. Wind. May have had a bit of a push but not much.

Again, no doubt she ran fine with regular as reported by just about very one here. The biggest difference was a definite boost with super when stomping the go paddle. Especially from about 60 to a 100. I did not play with the ect mode, just left that in standard. It seemed to kick down perhaps another gear which could be that the computer knew the fuel had more octane? Anyway, what a nice ride!

Truck stop in Louisiana
​​​​​​​

enigma25

Have driven Mercedes Benz for the last 25 years, all with V8's, and they all specified 91 octane, so that's what I used.

Now I'm driving my first Lexus, and I'm going to follow what the car specifies.

If the company that engineered the vehicle says 91 octane, then that's what I use.

Just my .02