It's been another 2000 miles since my last post a couple weeks ago and now I have a little over 36000 miles.

My gas mileage has been consistently very high compared to the specs especially the last 10000 miles even on mixed city and highway driving. Here in the San Francisco area it's not perfectly flat either and my highway driving I typically drive around 75 MPH.

Averaging 540+ miles per tank till refill of 22+ gallons. Sometimes I just fill because I don't trust the fuel gauge.

On my 2000 S500 I would typically get 490+ on the same 22+ gallons which significantly less.

Does anybody else get the same? Curious because it's not like I really have to try hard to get this mileage.

i love the gas mileage on my new s550.....i get around 26 doing 70mph on the highway. But it takes a few miles for the computer to adujust cuz it always starts out at 20mpg. And that was with low tire pressures. I feel green.

T

The S550 did get an award for being extremely environmentally friendly... it was mentioned on top gear or one of those shows.

I'm impressed with these numbers. Mine are significantly worse.

I've had the S550 4matic for 1500 miles and getting and average of 16.7 mpg at an average speed of 35. Even on the highway I haven't done much better than 23 mpg.

Hey....28.1 on the Hwy.... not bad on the mileage for the S550, I dont know why Mercedes would say 16city and 24hwy. I guess its all how you have your foot on the pedal

Yes they get great mileage...so why do we pay a gas guzzler tax?

It gets better with time. Also I hope your using premium gasoline. Plus the additional weight of 4-matic doesn't help much with the fuel economy, but it will get better with time. Let the engine loosen up a little.

awakening an old thread - just for yuks. my latest mpg highway numbers: 31mpg! on my 13,000 miles (broken in now) 2007 s550 4matic.

to wit: (a very boring) 60mph for 500 miles trip with windows/roof shut and the air conditioning on last week. chicago to pittsburgh via the turnpike system. 31 mpg!

on the return trip (pittsburgh to chicago), i did 72mph for the same 500 miles (obviously) with the windows down and the air conditioning off, and i got 28 mpg and a sunburned left arm!

this little unscientific study makes me love the s-class even more. and makes me smile when i see adverts on the tele for saturns and toyotas boasting about their 30 mpg highway driving. i blew those claims out of the water driving an arguably MUCH better luxurious auto.

thought you all might like to read about my little trip and the results. i know we don't buy these cars to save on petrol and by owning one none of us care about the $100 fill-up, but i wanted to test what it could do given i had the time and all. and to shove it back in the faces of those that tell us that we drive gas guzzlers. not necessarily the case, 'eh?

prius my ***!

Interesting data, ajm....

I get some ?6MPG in my daily <5mi urban commute....and some ?11MPG on my wkend pleasure drives on fast fwys/mtn twisties (but I accelerate and decelerate through various speed ranges for sheer sport and aural enjoyment)....

Expect to get an additional 1-2MPG when I "economize" by getting an '09 CL65 in Fall.....presumably, bigger motors don't need to work as hard as a humble 63 when pressed for perf....

Per my value judgment, any MPG data need to be risk-adjusted by healthcare costs/disabilities/oppty costs of lost wages, etc likely when alleged econoboxes are involved in a collision, vs same scenario w/a new S/CL.....

Are any of you guys using the ZAS cylinder shutoff? Just curios

The current S class does not use that technology as far as I know. (If you are referring to that system that would shut off half of the cylinders when not under a heavy load). The last I heard of that was in the W140 models. Can anyone verify what I'm saying or correct me on this. I've never owned a 12 cylinder until now so that tech knowledge is over my head.

It was introduced on the W220 in 2001, never on the W140 I believe. The only US model to use it was the normally aspirated S600. It was dropped when the turbos were added in 2003. It was used on V8s in Europe, but never here. I don't know for how long it was used in Europe.

I also don't think the latest engines use it.

BTW, the EPA ratings are for 100% gasoline and not the 10% Ethanol blend that we have here in CT. Since ethanol has less BTU's per gallon, gas mileage decreases approx. 0.5%, but the air is cleaner.

Incredible mileage numbers - 31 ??? My prior W220 was in the high 20's but your mileage is fantastic - much higher than the window sticker estimates. As a sidebar, my CL63 which gets 12-13 around town pushes 23-24 on extended highway drives.

Yet we pay a freaking GAS GUZZLER tax.

It costs $ 218.00 to fill up over this side of the Pond. I agree with the mpg i've just covered 10,000 miles and I'm getting on a run 28 to the gallon.

here's some more anecdotal evidence from my 07 s550matic that i bought in may 07. yesterday, i scrolled to the screen in the dash called, "after reset," and here are the numbers. this represents the overall mileage since i took delivery of the car (as i never 'reset' this menu as i wanted a 'lifetime to date' set of values) circa 15mos of ownership.

12,939 miles
429.11 operating hours
30mph (average, i guess)
bang on 20.0mpg

therefore, if you trust the computers, i have a lifetime average of 20mpg for this 400hp beast; i'm not sure if that is good or bad?

admittedly, i have something of a light foot and usually (but not always) drive in 'c' (comfort) mode. i think the 7 gears makes the difference, though. to wit: when i was driving to chicago to pittsburgh per my original post above, the rpms were indicating 1,500; the engine just isn't working that hard at 60mph.

this is just my historical experience. carry on ,,,

if you average 30mph, your car isnt even close to being in 7th gear. The benefits really kick in when you are around 65 to 70mph so you can stay in 7th gear and really reap the benefits of the transmission.

sorry - i don't think i was as clear in my post as could have been: i meant the 7 gears help at interstate speeds; thus, the 30mpg figure i get when i am on the interstate. i know at an average of 30mph over the life of the car to date that i am not always in 7th. only at interstate speeds. cheers.