LarryParker

In my previous 1992 ES, I used regular unleaded gasoline, because the car ran fine. I got 23 mpg when mostly on the highway. Last year I got a 2000 ES, and I got 24 mpg on regular. OK, fine. But when I was going to drive from So Cal to Las Vegas during June, I decided to run premium, due to the grades and the 100+ degree weather. I was surprised to get 28 miles per gallon, a 4 mpg increase over regular unleaded.

So I definitely used premium on a recent 4,500+ mile trip from So Cal to the Midwest and back. I brought my calculator, so I could check the mileage at each fill-up. I got 30 mpg!! I was getting 500 miles per tank, without risking running out of gas! This was running at 70 to 80 miles per hour with the air conditioning on about half of the time. The increased mileage more than made up for the increased cost of premium over regular. Although in-town driving is hard to get a comparison on regular vs. premium, because of the variations in driving conditions on each tank. But I guess I'll continue to use premium.

MJH

Are we supposed to be using unleaded of premium?

Pheonix

The MZ & GR engines run relatively higher compression ratios than the VZ engine. The MZ's also have problematic knock sensors that can be overly sensative.
Running premium in them will about always give more power, but more mileage will really be mroe on a car to car basis.

Fill up with premium, reset the ECU & try it & see.

miltonlin

30mpg is unheard of, even if it is all highway!

Is the trip from So. Cal to midest, all downhill?

amf1932

Not so! I just got back from a round trip I made from New York City to Washington DC.....about 500 miles, in my '07 ES350, w/the climate control on for the whole trip and I averaged 30.5mpg! And this was no BS!

miltonlin

Ok, what I meant to say was that for a 97-01 ES300 (EPA rated 19/25), 30mpg is astronomically good. For those model years, we only have a 4speed transmission.

amf1932

Yup, the 6 speed transmission in the ES350 does make quite a difference in the fuel economy.

mooseboy84

I have used 87 octane with my 96. When I let this tank run down, ill try premium for a chance and see what happens.

LXMN

Always use premium. You drive a LEXUS, treat it with respect and it will do the same back. Even if it is a toyota engine.

TheRupp

Wow man that's great!

Unfortunately I'm lucky to break 20 for some reason

ESpair

With 138K miles on a '97, I've gotten about 29.5mpg at an average speed of 72-73mph with premium gas and without A/C; so yes, you can get this kind of mileage with a 4-speed. With 165K miles on a '95, I've gotten just over 26mpg at an average speed of 72-73mph with A/C in moderate weather and with regular gas. This gas mileage difference doesn't surprise me because the '97 does feel more powerful (like it's breathing easier), even with premium in both cars which is usually the case. I tried regular on a recent trip because I guessed that when the engine isn't working hard (highway cruising), premium doesn't really help. You feel the difference with premium during hard acceleration because the higher octane allows the timing to be advanced more, without predetonation, yielding more power.

TheRupp

Good lord, you guys are getting excellent mileage off these things. I've never ever gotten above 24.8, and that was all highway at about 70-75 mph. Off the highway I never really get anywhere above 20... very odd