eschwart

Thanks.
What's the deal with fuel rating and mpg? Have heard conflicting info on this. Some say not possible for octane rating to affect mpg based on the physics of how the combustion occurs. But dealer makes a big deal of this saying published mpg ratings are based on 91 octane gas. Seems odd that there should be a difference of opinion on this - not rocket science. I guess the proof is in the pudding - will try 87 and 91 and see if there's a difference and if so whether large enough to justify the additional cost of premium.

Anyway I love this car - very glad I bough it.

Happy driving.

Richard95

In my area there is no 91 octane, only 87, 89 and 93.

eschwart

I spoke to a Lexus mechanic who claims that anything lower than 91 octane will cause pinging forcing the commuter to compensate by timing changes etc. He says that engine damage could eventually result. Does anyone believe this and can one get the "truth" on this issue?

dreyfus

No, I'm not buying it. The computer automatically retards the timing to prevent pinging when required.

I've run over a thousand miles using 93 premium and also our 87 regular gasoline, noting the performance, engine noise, and manually-calculated mpg. I've found absolutely no difference in any realm - performance, sounds, or mpg. I'm sure with careful instrumentation measurements one could detect a difference, but for my everyday driving it didn't matter at all.

So for the last 90,000 + miles I've used only 87 octane. I get 32-34 mpg on the highway and around 26 local mixed driving.

kewl

My experience matches that of dreyfus. While you might detect an improved quarter mile run on 93 fuel, in everyday driving I cannot detect a meaningful difference in 87 versus 93 fuel.

LexBob2

It's interesting that the 2011 and 2010 ES350 are both rated at 19/27 mpg. The 2010 on premium and the 2011 on regular.

garsarno

That's it. If there is really no difference, than regular it will be from this point on. I go through about 10 gallons / week. There is about a $.25 / gallon difference between regular and premium here in Northeast PA. That's $2.50 per week X 4 weeks = $10 per month X 12 months = $120 per year. That's the equivalent of buy three / get one free Kumho tires per year.

extreme78

New, poroud :-) owner of 2007 Es 350 here.
Took my car for a first "longer" trip and got 28MPG average, with regular gas, 70% highway 30% city driving. Moderate driving. Im VERY happy with the fuel economy, its better than my VW Jetta that I just got rid of.
I drive a lot and now I accually like it !

2008ES

If you're looking for an easy way to keep track of mileage, check out fuelly.com. A simple mobile version comes up on your smartphone with three slots -- odometer, gallons and price (optional). Takes just a few seconds to fill in the numbers at the pump. When you click OK it gives a complete report for that tank and your running averages. You get charts and graphs on the full version of the site as you continue feeding it fill-ups. The site does just this one thing and does it well -- no ads or pop-ups. I kept track of my Toyota for over a year and have been using it for my Lexus since trading cars.