S Class W221 MPG

[daveoffshore]

Hi

New owner of S350 CDI and a little surprised at the mpg I am returning -
around town getting just on / around 30 and a recent motorway drive of 150 odd mies at sensible speeds returned 43 mpg - am I about average?

What should I consider doing to obtain max mpg - specialist tune up or give to my local MB specialist to check things over?

Thanks

 

[C280 Sport]

How many miles?
Make sure the plugs and filters are clean and changed. Is your car in need of a tune up? What about driving conditions? Do you run your A/C system? Heated Seats?

 

[toolman1954]

Hi,
S350 CDI, you do not quote year, but I would assume it to be about a 2010 model blue efficiency model.
For a start, winter is a bad time for comparing fuel consumption for Diesels ( lots of other threads about Diesel consumption).Yesterday I drove down from Scotland, a 400 mile journey which normally I can see 47 plus mpg out of my old girl with 225000 on the clock, but yesterday she struggled at 43. Around town I get 30 ish, which, to me, for a big heavy vehicle is fine.
Your figures are not so much different even though you have a V6 and I see the Road Test Report averages your consumption at 37 mpg. I find the figures for the big Diesels quite amazing at times, and summer time you will see an increase. Does this help your surprise? I assume you expected more? You would not get anything close to these figures out of a V8 petrol.


( A suite of small changes are designed to make the S-class more efficient. The automatic transmission disengages at a standstill, for instance, reducing the load on the engine and quietening things down; it re-engages the second you take your foot off the brake. Lower rolling resistance tyres are pumped up to 2.6 bar, while smoother door mirrors, headlamp seals and an undertray drag the aero figure down to 0.27. It’s a slippery customer, the new S-class.

The result? The S350 CDI averages 37.2mpg and pumps out from 199g/km of CO2. Our particular BlueEfficiency model was the lounge-worthy LWB model with a rather confusing Eco-Power Engine Kit (a £1584 performance upgrade pack – on a green eco special!) that nudged consumption and emissions up to a still impressive 36.7mpg and 204g/km. Car magazine ....Mercedes S350 CDI BlueEfficiency LWB (2010) review by CAR Magazine

Steve.

 

[Conquistador]

That's pretty much what I get from mine (2012 S350L BlueTec). It is a big heavy car so I'm fairly happy getting 35mpg around town and 45mph or just above on a decent run.

For comparison, I averaged 39mpg driving a new RR Sport SDV6 for 4 months last year, exactly 34mpg running this current SDV8 for a couple of months so far, and a big 5.2 V10 Audi... you don't want to know

 

[geraldrobins]

Hi

New owner of S350 CDI and a little surprised at the mpg I am returning -
around town getting just on / around 30 and a recent motorway drive of 150 odd mies at sensible speeds returned 43 mpg - am I about average?

What should I consider doing to obtain max mpg - specialist tune up or give to my local MB specialist to check things over?

Thanks

It seems pretty good to me. Are you surprised because the mpg is better than expected or worse?

 

[stwat]

No offence intended but, it's not the kind of car to own if you're concerned about MPG figures.

 

[toolman1954]

As a further thought ...... there are some interesting threads in this section about remaps for the 350 diesel engine, perhaps that might be something worth considering??

 

[daveoffshore]

Thanks for all the comments - sorry I missed out from original post but my S class is a 2012 version

I took it to local MB specialist (not used previously) today - suggested

the full C service when due in June or at 58k (now 52.5k) approx £400
Full gear box service approx £250
Terra-clean air side & fuel side approx £150

Took to another local MB specialist which I have used many times

C service approx £504
Gear box approx £140
Advised against Terra clean or fuel additives as MB dont recommend

So will wait and see when the time comes if things improve and report back

 

[HB]

Thanks for all the comments - sorry I missed out from original post but my S class is a 2012 version

I took it to local MB specialist (not used previously) today - suggested

the full C service when due in June or at 58k (now 52.5k) approx £400
Full gear box service approx £250
Terra-clean air side & fuel side approx £150

Took to another local MB specialist which I have used many times

C service approx £504
Gear box approx £140
Advised against Terra clean or fuel additives as MB dont recommend

So will wait and see when the time comes if things improve and report back

Gearbox service at that price is too cheap at the second garage. Make sure they are using the correct mb oil for this car or it will lunch the box in due course.

Your mpg is fine, don't forget it's a big heavy beast.

 

[Flash]

As HB said make sure when doing gear box service the garage complies with correct MB Job Sheet Spec. For my CLS it is 236.14 for the 7G box.

 

[daveoffshore]

Thanks for the info regarding the gearbox work

Where can you get hold of the MB work spec sheets for both the C service & full gear box service

I have so much to learn so thanks for all help / direction appreciated

 

[Lagerlout]

43 MPG out of a W221 on a trip is about the best you're going to see. 30 mpg around town is pretty good too. Sounds right to me. My W222 does about 33 around town and I get about 37 barrelling down a motorway. Best I've seen is about 44 mpg setting the auto cruise at 70.

 

[StuartK]

Sounds right she's a beast remember.

 

[nicholas15]

After 4,500 miles I am averaging 40.5 on 2012 S350 Bluetech; mixture of motorways and rural roads

 

[Shala]

Hi

New owner of S350 CDI and a little surprised at the mpg I am returning -
around town getting just on / around 30 and a recent motorway drive of 150 odd mies at sensible speeds returned 43 mpg - am I about average?

What should I consider doing to obtain max mpg - specialist tune up or give to my local MB specialist to check things over?

Thanks

Hi
I got my s350 from mercedes in may and it's due c service in 18 days. In town. I.e local shopping and school run I get 19-21mpg if I stop at couple of traffic lights. I don't rev above 2k. When the car hits peak traffic I see 15mpg. I bought it as I say the car town mpg as 21mpg. Has the car got issues?

 

[john,cook109]

Mpg

Hi
I got my s350 from mercedes in may and it's due c service in 18 days. In town. I.e local shopping and school run I get 19-21mpg if I stop at couple of traffic lights. I don't rev above 2k. When the car hits peak traffic I see 15mpg. I bought it as I say the car town mpg as 21mpg. Has the car got issues?

Just been to Scotland and back a round trip of 1300miles at 41mpg@ 65mph best I have ever managed. I am happy with this trouble free trip.
:bannana:

 

[Shala]

Just been to Scotland and back a round trip of 1300miles at 41mpg@ 65mph best I have ever managed. I am happy with this trouble free trip.
:bannana:

Yes it's very good on long motorway drives. Its the local drives that kill the fuel

 

[Submariner1]

Hi
I got my s350 from mercedes in may and it's due c service in 18 days. In town. I.e local shopping and school run I get 19-21mpg if I stop at couple of traffic lights. I don't rev above 2k. When the car hits peak traffic I see 15mpg. I bought it as I say the car town mpg as 21mpg. Has the car got issues?

Doesnt sound very good to me. In warm weather I would get 24-25mpg around town taking it easy. Pushing it a little and this would drop to 21-23.
In the recent cold spell that dropped to 23 mpg around town driving gently. And 19-21 driving fairly smartly.

Once, pushing it really very hard [to on the edge of wheel slip] in cold weather (of course once coolant temp got to 90C) I saw 16.9 mpg, pressed reset, and it recovered to 17-19 mpg in slow traffic.

To me thats pretty good for a CL500 5.5 Litre (its, a big heavy car with plenty of go in her) but then I dont think people who buy big engines care too much.
I only check it , purely to make sure the engine is running properly etc.

Mine's done 40K and is now 7 years old.

I assume yours is a 3.0L , age?? Mileage?? For a diesel thats doesnt seem great.
But I am no diesel expert, I had use of a really old 270 CDI, that would show 23-29 around town and 40-43 pushed very hard on a long trip.