Drove to the dealership this morning and acheived a remarkable 31 MPG. Cold start, mostly highway driving, and moderate traffic.

 

Thats pretty amazing for the GL350. My GL350 only averages 22 mpg which is a little bit disappointing. However, I do a lot of city driving as well so thats probably the reason it is so low. My car just hit 1000 miles and I have had the car for 2 weeks now (I drive approximately 100 miles a day) and I have only averaged 21.

 

amaycg, I avareage about 25 MPG combined. I was doing about 62 MPH on the freeway. THe car has 700 miles on the odometer. I can only hope it gets better.

 

Mine is 320.... and I think this diesel engine does impress me...

From Tahoe to San Fran... start very cold (for me 20*F), 2 adults, full cargo, traffic outside Tahoe (snow), stop 2x (restroom & lunch), ~200 miles.... got an avg. of 27.6mpg.

Since I bought it (6 mo. & 9K miles ago), I've got 21mpg - mostly city driving.

Amazing....

 

Hmmm...maybe my car is just weird.
I was surprised at my MPG because reviews on Yahoo autos and KBB show me people are averaging more than what is listed on the window sticker.

How much city driving do you guys do?

 

Couple weeks ago, driving downhill our GL450 got 24.6mpg from tahoe to placerville signals on US50. It has 40K miles on clock now. Diesel will give getter mpg than gas engine. But I was impressed with 24.6mpg that I achieved for about 50+miles of driving. Overall, I am getting 16.3 mpg for 24K+ miles of driving.

Regards,
Kamal

 

Actual undoctored photo - I win!

(PS That was downhill coming back from Flagstaff, repeatedly hitting the reset button as the MPG got higher and higher.)

STP

 

Wow! 51 mpg is amazing for a GL. What screen are you looking at to find your mpg? Maybe I am looking at it wrong or looking at the wrong screen because my screen does not look like the pictures. Maybe I might be averaging 22 mpg only for city... But congrats you guys on the miles per gallon!

 

We saw mpg in the 70s on our E-class in similar circumstances, i.e. Cloudcroft to Alamogordo, NM. IIRC I even used a little engine braking a couple times.

Saw 30s on my GL for a bit with a very significant tailwind. This wind direction changed later and it went to the teens, all in the same 60 miles.

 

the mpg is usually not very accurate

fill up, reset, drive for 500 miles, fill up, calculate true mpg...

mine is waaay off... the readout is about 20% pessimistic

alex

 

I've gotten over 100 mpg before. There's this place by my house that has a really steep hill. After I get the 320 going from the light at the top of the hill, I put her in neutral and shut her down. You've got to hold down on the start/stop button for a few seconds but once you do, boy that baby just sips fuel! Oh and did I mention, it's real quiet. Just the wind.

 

31 is impressive. My wife's '09 Bluetec gets about 18mpg around town. 25 seems to be best it does on highway driving.

 

+1.

Our '08 averages about 18 mpg in the city, and about 23 mpg at 78mph on the highway. Total life-time average is about 19.8 mpg.
The best we've seen was coming back from skiing in Colorado when the trip computer showed an average of 25.9 at an average speed of 70 mph. Never been able to beat that. I find anyone managing 31 mpg on flat terrain at decent highway speeds must be very lucky.

Bish

 

Trip computers can be deceiving. The only real way to know is miles/gallons and that is a little subjective unless your sample is over a long range of miles. Our '08 is right in line with yours. Our GL sees very little city or highway only miles and we are averaging 22 mixed city/burbs/highway.

 

Mileage acheived going up on slight grade from Woodbury, CT to Hartford, CT. My car reads only minor deviation from actual. Odometer miles less than actually travelled per 10 actual miles. Averaging 25.5 mpg now with mixed urban and 30% highway.

 

Hey, I just wish EVERY trip was downhill!

 

Sort of like the Irish prayer:
May all your trips be downhill
both ways,
and the wind always at your back

 

I don't think any of these figures (those much over 30 mpg) are accurate indications of the vehicles overall fuel economy. I mean you could easily get a 99 mpg reading just be resetting the dash at the top of a long hill and recording the figure at the bottom.
The indicated fuel economy is (subject to the vehicle of course) pretty accurate as an average value; drive a 2 or 300 mile round trip and check actual fuel consumption by filling up at each end and you will discover the average is accurate. What the dash shows is a short time frame average. Over the course of time it adjusts, giving you a running average.
No point in driving 300 miles, and coasting the last bit to give a false reading. If you want to know your actual economy on the freeway at a given steady speed then you need to reset the meter as you start your run and hold the throttle as constant as possible to maintain that speed. Hills will either increase or decrease the reading. We know we get 99 mpg with no throttle down hill and 10 mpg up a steep hill. Neither of these conditions represent normal, overall driving conditions. To know how efficiently you are using fuel you need to remove all the variables like hills, head wind, heavy loads etc and use the meter to give you an average over as long a period as you can. Then if you can, avoid excessive hills that sap fuel economy.
Recently with a steady throttle on flat roads at 60 mph I saw 28 mpg. And when I drive a 300 mile trip on level roads with few hills, the average is around 27 during most of the trip.
Whichever way you look at it the GL is pretty reasonable with fuel. I say pretty reasonable because there are many other engine systems that could give us more but are surprisingly not available.

 

I have the ML CDI, (same motor, a little lighter) and my best was about 32MPG. Flat highway for about a 50 mile drive, about 50-55 MPH, and all the tricks I knew to economize.

Nowadays, I am seeing 25-28 on a regular basis, same roadway with speeds about 60MPH. (Unless it's below freezing, then it drops to 23MPG.)

For you new buyers, as the vehicles get over 16000 miles, the mileages will increase again.

Bottom line, enjoy the fuel sipping benefits of the diesel.
And take pics because your non diesel friends won't believe.

 

Round trip I am getting 28.7 mpg on average (to and fro destination)/

 

+1 on that! I'm getting about 25-26mpg on highway driving, even at the 80mph+ speeds you can get on some of the open, clear areas on I-10 in Arizona (where the limit's 75 and not doing at least 80 will get headlights in the rearview pretty quickly), and a little over 19 in the city. I do not trust the trip computer, as it's a) easily fooled and b) usually optimistic in mine (reports of the pessimistic version notwithstanding).

STP

 

OK I have to go back and eat my own words somewhat.
Just drove Seattle to Portland round trip 380 miles (610 km). Roads are mostly flat staight and with plenty of room to drive in economy mode without holding people up.
Average speed was just under 60 mph (96 km/h).
Trip down was with an empty vehicle. Trip back was loaded with 2000 lbs ( 890kg) of metal components.
Economy on the way down was 31.5 mpg
On the return it dropped to 29.
Pretty good for such a large vehicle.
And for all those people discounting the 350 because of its lack of horse power I can state for a fact that overtaking from 60 mph was a breeze even when loaded. There is so much torque it makes up for the lack of HP. (remember that HP= 2 X pi X rpm X torque). Nice lazy engine speed and tons of overtaking grunt when needed. Top speed was kept to around 75 mph (120km/h) but only for passing.
Very happy with this vehicles engine configuration and performance.

 

how about 90 mpg? lol i did this coming down the grapevine going north on I-5.