Was driving from Houston to Ellington Airfield (South of Houston) and back...hit 35 MPG - for a short period of time...I was happy my 250 is capable of such feat.

 

Highest I've seen is 30.0 All freeway. That drops as soon as i get off though

 

Must've been a lot of downhill, I've achieved 43mpg tank average before from going downhill for couple of hours from a camping trip.

 

wow, Highest ive done is 30ish too

 

if you drive on the freeway without many inclines you can get close to 40

 

must be nice. my friend's 250 is getting 26mpg max i've seen. my 350 is getting 22mpg max. mostly 19.5mpg
btw, i'm in the bay area CA

 

^x2.. i'm always between 19.5 and 21.5
i'm all city, barely ever on the highway.

 

I got around 27 mpg from nyc to west DC and back considering all the hills from Delaware to DC, local driving around 20-21 it 's quiet good for an 08 IS350. only mods F Sport intake and exhaust.

 

In Florida (really flat), I get 32 MPG driving highway. I average 28 MPG every week driving 60% HWY and 40% city. I wondered if I have an exceptional engine or a faulty computer

 

Nice! I've got mine to hit 40+ for a short time, but it always drops back down really quick once I go up a hill or get back on the streets. I'm impressed with the gas mileage of the 250 too. I will break 500 miles on a tank ONE day....lol I got it up to 485 miles once on a road trip and had 17 miles to go...but had to fill gas because there was gonna be a while till the next gas stop =/

 

I usually average 32-33 @ 80 MPH hwy and im at 26-28 city and thats rollin on twinksters. Odd? not really i dont beat on my **** thats why!

 

That's what she said

 

You always get the highest computer numbers after filling up and getting on the freeway. Remove those two factors or shut the car off to start over again and it all goes to hell.

 

The highest I usually get is about 34 mpg on the freeway. 40+ now that's insane.

 

I usually get 22 MPG on my 250