Real world E350CDI fuel consumption (comparable to 320CDI?)

[Jolltax]

Wife and I are seriously looking at E class diesel estate when they are out next year. Lease on our XC90 finishes in April, currently favour the E250CDI or, as we will have an automatic, the E350CDI also looks only a little more expensive. We have always had Audis before the Volvo but fancy a change....

I am wondering what the real world economy of the E350CDI will be like, is the engine the same as the current/old E320CDI ? - if so I can search for posts from owners of the E320CDI estate and get a bit of confidence. I guess this would give a good idea? The official combined figure for the E350CDI saloon appears to be 40.9 mpg, our experience suggest this will be about 30% high for our kind of driving.

I guess I would be happier with an average of 35 mpg plus and the larger engine refinement / driving of 350.

We constantly drive on small hilly country roads A/B, not much town or motorway and do 18-20k per year. Our current cars offical combined mpg figure is 33 mpg and we struggle to get 25 mpg - a fairly big difference. No, we do not drive hard / fast! (unpleasant / impossible in an XC90 imho)

Hoping to see an estate E350 in a showroom soonish and will be visiting the Worcester dealer in December to make some enquiries and see if we can drive a saloon style to get an idea.

Thanks for your advice in advance!

Jolltax

 

[timskemp]

Hi Joltax.

The big advantage of the 350 over the 250 (other than the engine) is that gearbox. 7th gear is amazingly long and gives great cruising economy, I spent a few months in a loaned E280 (mine is an older 5 cyl E270) and it was far better on the motorway for economy than mine, but in town driving was slightly worse.

The main thing you'll see over your XC90 is that the smaller frontal area, lower drag, lower mass and lower rolling resistance will see you a significant reduction in fuel consumption.

The 250 will be more economical in traffic by virtue of using less fuel at idle and weighing slightly less, but I don't imagine it being worth the saving....

 

[Mactech]

As you have noticed, one persons real world is not the same as anothers
I have had two E Class estates in recent years an 05 220 and an 06 280 diesels. Whilst I have no doubt that the new cars will be a small improvment over these the comparisons are still useful.
My 'real world' is mainly long distance on A roads and dual carriageways.
E220 estate 46mpg
E280 estate 42mpg
S320 44mpg
ML320 36mpg

My wife's 'real world' is a nine mile trip each way in to the city, with the same cars:
E280 estate 32mpg
ML320 30mpg

My experience suggests that in your 'demanding' real world of hilly roads you will probably be worse that the manufactuers overall figure in any car.
The reason I went for the 6cyl car was not so much what it does but the way that it does it. You will understand that when you have driven both.
Can you guess which one is entirly effortless?

 

[Druk]

They will be in different roadtax brackets if that is a consideration. Probably not vast now but in coming years things may escalate and widen the difference.

 

[Jolltax]

Thanks for the impressively fast responses!

I am very confident that E350 will be a significant improvement for us, as people are saying - a test drive will probably sort this out for us and give us an idea of the relative merits E250 vs E350.

Jolltax

 

[st4]

new e250cdi has a very wide spread of torque, not that different to v6 engines but the refinement wont be nearly as good (its worse than a 220cdi apparently) and its had a fair few injector issues such is the complexities of 100bhp/litre from a diesel. I'd take the 6pot car in balance.

 

[C240Sport97]

an 350CDi (std auto) is only about £1500 more expensive than an E250CDi auto.

Well worth it as you get:

1. a V6 .. much smoother, and more torquer for longer
2. a much better gearbox in the 7G-tronic
3. 80 litre fuel tank
4. direct steer
5. clear center console, as gear selection in on steering column
6. s/w shift paddles
7. double exhaust pipes

 

[Jolltax]

an 350CDi (std auto) is only about £1500 more expensive than an E250CDi auto.

Well worth it as you get:

1. a V6 .. much smoother, and more torquer for longer
2. a much better gearbox in the 7G-tronic
3. 80 litre fuel tank
4. direct steer
5. clear center console, as gear selection in on steering column
6. s/w shift paddles
7. double exhaust pipes

My thoughts exactly and the only slight concern I have is with the fuel economy, the reason for my post!

You guys/girls(?) are all being very helpful, thanks

Jolltax

 

[C240Sport97]

some info below:

Six-cylinder CDI engine: higher output and torque but lower fuel consumption
In a similar vein, the V6 diesel engine for the new E-Class is one of the most sophisticated compression-ignition units on the world market. It offers substantially greater output, comfort and driving enjoyment than other engines thanks to the immense torque of 540 Nm alone, which is available between 1600 and 2400 rpm, ensuring outstanding agility when accelerating from rest and exemplary flexibility when accelerating in any gear. To put this into figures, the E 350 CDI BlueEFFICIENCY model (170 kW/231 hp) accelerates from 0 to 100 km/h in 6.9 seconds and from 80 to 120 km/h in 5.1 seconds.

Despite the higher output and torque, fuel consumption has been reduced by 0.5 litres to 6.8 litres per 100 kilometres (NEDC combined figure), equivalent to 179 grams of CO2 per kilometre. The 7G-TRONIC seven-speed automatic transmission is specified as standard for the E 350 CDI BlueEFFICIENCY model.

The Mercedes engineers have gone to great lengths to optimise the technology at the heart of the V6 diesel engine, reducing the compression from 17.7 to 15.5, enhancing the turbocharger with a more efficient EGR cooling zone, switchable bypass duct, ceramic glow system, modified injection nozzles and optimised air ducting.

Much more here:
The 2010 Mercedes-Benz E-Class:  Drive System | eMercedesBenz - The Unofficial Mercedes-Benz Weblog

 

[fredT]

if you're running a brand new mb i dont think the difference in fuelconsumption would make or break the deal..

think my c320cdi has done around 32 combined since i got it, half scooting around london half running up and down the m1 to leicester

the main benefit over the 250 (220) will be that it doesnt sound like a tractor

 

[gIzzE]

I have been thinking long and hard about the E250cdi, however...

I want, comand, upgraded hi-fi, leather, auto, 18" wheels, bluetooth, and xenons.
Now, by the time I have specced. both cars the E350cdi works out cheaper because of the residuals.
The E250cdi is great if you don't add any options, but add some essentials and it no longer makes much sense.

 

[oldcro]

I recently changed my W204 C320CDi for an E350CDi and so far the fuel consumption is about 1 mpg less driving the same routes. As the E350CDi has only done about 600 miles it should improve as everything loosens up. The C320CDi averaged 35.7mpg over 2,200 miles according to the cars computer. The E350CDi is averaging just under 35mpg. Like your self, no motorway driving and many hills.

Go for the E350CDi, it is a great car and I have no regrets about changing models.

Just realised you're comparing the estates, while I have the saloons so not sure if there is any difference in consumption figures.

 

[Diesel Benz]

I recently changed my W204 C320CDi for an E350CDi and so far the fuel consumption is about 1 mpg less driving the same routes. As the E350CDi has only done about 600 miles it should improve as everything loosens up. The C320CDi averaged 35.7mpg over 2,200 miles according to the cars computer. The E350CDi is averaging just under 35mpg. Like your self, no motorway driving and many hills.

Go for the E350CDi, it is a great car and I have no regrets about changing models.

Just realised you're comparing the estates, while I have the saloons so not sure if there is any difference in consumption figures.

Your W204 320 CDI had basically the same V6 CDI engine as the current E350CDI has. It was not clear from the post but I'm guessing the question would be about the older I6 320CDI versus the current V6? The old I6 without any particle filters and lower EU emissions grade was very efficient and even if I have not compared my book keeping, I would expect the new engine consuming a bit more fuel, even if it has the 7G-tronic tranny which helps at highway.

 

[scumbag]

I recently changed my W204 C320CDi for an E350CDi and so far the fuel consumption is about 1 mpg less driving the same routes. As the E350CDi has only done about 600 miles it should improve as everything loosens up..

one would assume that there is quite a difference in weight between these two. To get within 1mpg is a pretty good show of efficiency so I guess there must have been some improvements in the engine between models.

 

[Jolltax]

The C320CDi averaged 35.7mpg over 2,200 miles according to the cars computer. The E350CDi is averaging just under 35mpg. Like your self, no motorway driving and many hills.

Go for the E350CDi, it is a great car and I have no regrets about changing models.

Just realised you're comparing the estates, while I have the saloons so not sure if there is any difference in consumption figures.

Thanks this is very helpful, sounds like we do the same kind of driving, I think I can live with 35 mpg ish.

I fully expect the estate to be slightly less efficient but I don't think theres a massive difference in weight and I doubt drag will be a huge factor at the speeds we travel so it gives me a good idea.

Thanks!

Jolltax

 

[horsesuitedfool]

Also, having owned an X5 Diesel Sport and an XC90 i can confirm that the claimed MPG figures on 4x4 are massively overstated and in real life you get nowhere near what they claim. In the Merc saloons etc both petrol and diesel you get much closer to the claimed figure, i drive a C270 and drive very spirited (as the manual describes it!!) and i get an average of 35mpg which is only 10% less than the claimed figure.....Get the 350 otherwise you will have to drive the 250 much harder and it will end up using more fuel because its working harder......

 

[oldcro]

one would assume that there is quite a difference in weight between these two. To get within 1mpg is a pretty good show of efficiency so I guess there must have been some improvements in the engine between models.

The way it is going I'm expecting the E350CDi to match or even beat the C320CDi on consumption as my mileage increases.

The active light system is another advance on the intelligent light system fitted to the W204. Say you're stopped on a dark road and select main beam, you remain on dipped beam until your speed reaches about 20mph ish and then main beam comes on. Then if a vehicle comes towards you or you catch up with a vehicle, the main beam dips enough so as not to dazzle anyone or switches off if close enough to the vehicle in front. Also main beam goes off where there are street lights and back on as required.

So the lights combined with Distronic Plus means all you have to do is steer the car. Now does anyone know how to connect the sat nav to the steering wheel?

Sorry to have gone off topic, but I feel like the kid who has just had the best toy ever.

 

[Barryh]

one thing to consider is the choice of model.I have a 280 Sport and get 33mpg over last 40K miles with a very mixed driving cycle,everything from town,steady 60mph and motorway.
The sport has 18" wheels which if you look in the catalogue/Brochure for E class shows differing CO2 values for wheel sizes.

As pointed out,driving styles and spec of car make the difference

 

[st4]

Barry, would you have been much worse off with an E500?