I think my calculator and car MPG display is on the fritz. My wife just returned home from a 1500 mile trip and she averaged 30 MPG going 75 MPH in our 2010 LS460L. WOW!

Very possible. I usually average high 17's to low 18's on road trips with an average in the 78 MPH range. Around town...not so much.

Very possible, with premium fuel you get premium results

Yes it is definitely possible. We did a 4000 mile trip last summer in our '08 LS460 and averaged 28.7 for the entire trip. The trip included some slow traffic due to accidents, construction and weather. We drove from south Florida to Pittsburgh, Pa through the mountains in the western portions of the Carolina's, Virginia, West VA and PA. Then we drove across PA into NY state, Mass and New Hampshire before heading home. Lots of back road driving as well as some city traffic in Boston, New York & DC.

On one 475 mile leg, we averaged 30.5 - all steady highway driving stopping only at a rest area on time.

Well I'm impressed such a big, heavy and powerful automobile can average 30MPG. Great job Lexus!

Not the first time numbers like yours have been reported for this car. I've been getting steady 7.5 L/100 km on the flats, which works out to about 31 MPG. Combined city/highway has been rock-steady at 22.5 MPG, and I live on the side of a mountain. (LS600)

Yep. I've posted here several times that I regularly get 30 and more on road trips.

Kind of puts the myth about V8's and bad mileage to rest, doesn't it?

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That's really good gas mileage. The best I've ever done with exclusive highway driving at 75 mph on my 2010 Sport is about 24 mpg. I wonder if it has anything to do with what I believe is more aggressive shift points on the transmission (similar to the IS-F). I'm a pretty aggressive driver but when I hit the 24 mpg I had the car in cruise control for most of the trip.

I get about 17 mpg with combined city/highway which is what I typically do.

Highway milage can vary dramatically based on the installed tires. Best results I have seen is using the Michelin GreenX Energy series of tires.

I know my Michelin Pilot Sport AS+ tires are costing me at least 3 miles per gallon.

Another factor is the ethanol content of the fuel. The more ethanol, the poorer the fuel milage.

Vern

Yeah, as mentioned by others on this board, 30 mpg highway is possible under the right circumstances.

I have gotten 30 MPG too on trips between Atlanta and Florida.

Greg