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Interested in purchasing an '09 Bluetec and reside in California so very excited about this engine becoming available here. Anyways, wanted to see what current owners are getting in terms of MPG w/ their CDI's. Just curious to see how accurate the EPA #'s (18/24) are for the vehicle.

Also, is anyone familiar with major changes to the '09 model from the current model. I read about the 20" tires, run flat tires, and better nav but not sure how accurate that is.

Many thanks for your time and look forward to reading your responses.
 

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GL320 CDI - 2008, '04 Touareg V10 TDI, '85 Unimog U1700, '83 Mitsubishi 4WD turbodiesel PU
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My 2007 GL 320 CDI routinely got 27-28 mpg (26 mpg on the sticker)
My 2008 GL 320 CDI usually gets less that 23-24 for the same driving (25 mpg on the sticker)
I note that the 320 CDI bluetec engines in the E class usually show abt 35mpg on the sticker. I'm sure a lot of that improvement is due the lower drag body but I get the impression the bluetec helps a lot.

Better NAV? I HOPE SO! I'm not very impressed with the Comand Nav (either year) The Garmin units are much better but are not, of course, built in.

20" tires? They may look nice but I'm not sure they do ANYTHING for your MPG. My 19" Contis' did NOT and I hade no choice of tire manufacturer. If you are ordering them as an extra cost option, SPECIFY the manufacturer you want [check with Tire Rack for survey results on-line]

Run Flats - you probably have no choice but they probably have higher rolling resistance (hard to get data) and are VERY expensive to replace if you actually have to use the run flat feature. Its a good bet the local filling station you will be stuck at will NOT have a new tire for you in stock!
 

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I have a 07 GL320 CDI and the best mileage I have gotten is 24 mpg on the highway. My wife does most of the driving around our suburb and the car gets 20 mpg average. This is all fine by me because we need an SUV and we were getting 11 mpg in our old Nissan Armada. We love the GL and I think my mileage on the highway is lower than others because we drive at a higher average highway speed than many others. I have seen flash trip computer readings of 28 mpg at a more sedate highway speed (65 mph or so) but the GL 320 just wants to cruise along at a higher speed.

I think that having only one all season tire choice in the 19" size is a big drag but the Conti tires did great last winter in some serious Vermont snow. I am due to replace them after the summer but there are no real choices unless I switch to a summer/winter tire combo and two sets of wheels.

Other than that I love the car and it has been bullet proof for us; too bad diesel fuel is fifty cents a gallon higher than regular gasoline.
 

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'07 GL320CDI
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Comparison with regular gasoline price is nonsensical since

There is no regular gas Mercedes

Diesel is efficient because of high compression; to compare to an efficient gasoline engine, you'll compare to a high compression gasoline engine ... which requires premium.
 

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I note that the 320 CDI bluetec engines in the E class usually show abt 35mpg on the sticker. I'm sure a lot of that improvement is due the lower drag body but I get the impression the bluetec helps a lot.
That would be the wrong impression.

The E-class mileage advantage is indeed due to the weight and aerodynamics and if the engine did not have the exhaust system treatement that is Bluetec, the mileage would be even better. NOTHING NOTHING NOTHING about Bluetec is a mileage improver--it's all about scrubbing the exhaust.
 

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...if the engine did not have the exhaust system treatement that is Bluetec, the mileage would be even better. NOTHING NOTHING NOTHING about Bluetec is a mileage improver--it's all about scrubbing the exhaust.
This is likely true. Yet, if in fact if the exhaust can be scrubbed very clean, then the engine can be tuned to allow more efficient operation, which would output more exhaust nox that Bluetec "fixes". So there could be that indirect benefit.
 

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GL320 CDI - 2008, '04 Touareg V10 TDI, '85 Unimog U1700, '83 Mitsubishi 4WD turbodiesel PU
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This is likely true. Yet, if in fact if the exhaust can be scrubbed very clean, then the engine can be tuned to allow more efficient operation, which would output more exhaust nox that Bluetec "fixes". So there could be that indirect benefit.
I believe that is EXACTLY what happens. Our (GL 320 CDI) engines MUST be 'de tuned' to meet emissions standards. The E320 CDI is able to be tuned to a much more efficient point (read higher NOX) and then the NOX can be handled by the water + urea mix at the Bluetec reactor in the exhaust system. Result, better mileage.:D
 

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"the NOX can be handled by the water + urea mix at the Bluetec reactor in the exhaust system".

From what I've read the above system is get get emissions to a new lower level as required for sale in certain states.
 

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I believe that is EXACTLY what happens. Our (GL 320 CDI) engines MUST be 'de tuned' to meet emissions standards. The E320 CDI is able to be tuned to a much more efficient point (read higher NOX) and then the NOX can be handled by the water + urea mix at the Bluetec reactor in the exhaust system. Result, better mileage.:D
Of course if you check the figures, you'll find a lower horsepower rating for the Bluetec E-class than for the GL, ML, and R-class CDIs. If you call lower horsepower more efficient, have at it.
 

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Of course if you check the figures, you'll find a lower horsepower rating for the Bluetec E-class than for the GL, ML, and R-class CDIs. If you call lower horsepower more efficient, have at it.
Peak horsepower output rating - the figures quoted in the literature - doesn't have much at all to do with efficiency as described by miles-per-gallon to get from A to B. Given the lower weight of the E cars, its not surprising that M-B detuned the engine a bit (and probably got a bit more EFFICIENT in the process).:surrender:
 

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Peak horsepower output rating - the figures quoted in the literature - doesn't have much at all to do with efficiency as described by miles-per-gallon to get from A to B. Given the lower weight of the E cars, its not surprising that M-B detuned the engine a bit (and probably got a bit more EFFICIENT in the process).:surrender:
Uhhh, thanks for that scientific conclusion. :):surrender:
 

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Glad you got it. Ikchris seemed to have missed the message.:)
 

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His 2013 RAM Cummins Turbo Diesel Laramie; Hers 2007 ML320 CDI P3; Kids 2010 "4Matic" Impreza
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Interested in purchasing an '09 Bluetec and reside in California so very excited about this engine becoming available here. Anyways, wanted to see what current owners are getting in terms of MPG w/ their CDI's. Just curious to see how accurate the EPA #'s (18/24) are for the vehicle.
If this helps, my ML CDI has adout 25000 miles, and today, driving 55-60 MPH on the highway, I got 31.4MPG. EPA figures are a joke. You will get much better mileage than posted, and more as the motor breaks in. Enjoy..:thumbsup:
 

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If this helps, my ML CDI has adout 25000 miles, and today, driving 55-60 MPH on the highway, I got 31.4MPG. EPA figures are a joke. You will get much better mileage than posted, and more as the motor breaks in. Enjoy..:thumbsup:
55-60 MPH on the highway, that's amazing. Nobody in California drives that slow, except maybe some Prius drivers.:D
 

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55-60 MPH on the highway, that's amazing. Nobody in California drives that slow, except maybe some Prius drivers.:D
I note that he said highway, not freeway. I'm not sure what he meant, but California thinking does not necessarily apply in the rest of the US:D
 

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I note that he said highway, not freeway. I'm not sure what he meant, but California thinking does not necessarily apply in the rest of the US:D
True. Amazing 55-60mph on the highway, sounds like a traffic jam in the making. But as California goes, eventually the rest of the country follows, (certainly the automotive industry knows that). :D
 

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Of course I realize that MB cars all take premium gas unless they are diesel. It's what I put into my E55 wagon. . . .I was just making the comparison to the cost differential with gas to diesel. Right now in CT diesel is fifty cents more expensive than premium gas. It's still cheaper than the mileage I was getting with my Nissan ARmada on regular gas. My mileage may get better but the traffic on my freeways moves up here at 80 so my mileage is about 24 mpg.
 

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03 Ferrari 360 09 BMW335d 99 E300TD EU SPEC 05 and 06 E320 CDI 12 E350 Bluetec Designo 06 Smart CDI
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I have a 2007 Bluetec and a 2005 and 2006 CDI. I find that the straight 6 CDI's get better gas mileage. From my town to Sanfrancisco (80 miles) I get 30mpg in the bluetec, 33.5 in my 2005 CDI and 34.5 in my 2006 with the Brabus D6 kit. Maybe the bluetec will get bettr gas mileage as it breaks in. I hope so.
 

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03 Ferrari 360 09 BMW335d 99 E300TD EU SPEC 05 and 06 E320 CDI 12 E350 Bluetec Designo 06 Smart CDI
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I had the same shifting problem with my Bluetec, but they reprogramed the transmission and it seemed to make it a lot better. Still not as smooth as the 5 speed auto in my CDI's.
 

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Sticker on my '08 GL320CDI was 18/24, but I rarely get under 20 mpg zipping around town and about 24 hwy. If I keep it under 75, mpg increases SIGNIFICANTLY!!!! Drove to Denver (561 miles) with the cruise set at 65 and got 28 mpg - still had about 1/2 tank left. My R/T to Southern California which was pedal to the metal experienced a .6 gallon difference in consumption coming and going - overall mpg 24.9. I've also driven to Sioux City (250 miles R/T with cruise at 60mph (while diesel was approaching $5/gal) and got 32 mpg. Aside from the lag, I'm very happy with the torque, acceleration and general performance of my diesel. Would recommend.
 
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