A question specific to the US forum members that drive a W220 S-class with diesel engine.
In the US there are quite low maximum speeds, this combined with long straight highways would be very suited for fuel efficient driving in my opinion.

What kind of mileage do you reach (both on the board computer and one calculated yourself)
I reach 7.5l/100km (or 13.3km/l) according the board computer and 9 l/100km (or 11.1 km/l) when I calculate distance between tankstops and tanked volume.

This is based on approx. 8000km that where about half city traffic and half highway with max speed 120km/h (75 miles/hr) Engine is 320CDI


regards

 

Unfortunately the S320 CDi is not imported by MB into North America so no one can answer your question. The only MB diesel imported with that engine is the E320 CDi.

I get about 25 mpg but since my car has 9,000 km I expect the mileage to improve later. The best way to calculate mileage is still the old fashion one: fill up the tank until it clicks, zero the odometer, drive till nearly empty and refill to full again. Divide the mileage with the volume of fuel pumped and you get the result 100% accurate.

 

I beg to differ. That method Is Not 100 % accurate!

If the W-211s are anything like the older W-210s, this will not be accurate.

I found that with both my '99 E-300 DT and my son-in-laws '97 E-420, it was impossible to get
the tank completely full unless you spent an additional 10 to 15 minutes slowly (very slowly)
completely filling the tank so that the fuel is standing without
foam, and is all the way up to the rim of the filler tube.

And to do this correctly, I found that it was best to always fill up at the
same pump with the car in the same exact position as the first fill.
The slightest change in the levelness of the filling spot can make a difference.

Simply allowing an automatic nozzle to "click-off" does not get you an accurate fill. Why?
Because the automatic nozzle will not always click off at the same point.

As we all know, most if not all, diesel foams like crazy as it is being pumped into your tank.

Unless you pull the filling nozzle back out of the filling tube towards the end of your fill and feed the fuel in as slowly as the nozzle valve will allow, and allow the bubbles to disappear, you do not have an accurate fill.

I had hoped that MBZ would correct this error with the newer cars, but I doubt if they have?

An even more accurate way to determine exact fuel economy is to calculate
your total gallons used over as long a mileage test as you possibly can.
Doing this will remove those slightly uneven fills if done over several fill ups.

Your new 2006 E-320 CDI should be doing better than
25 mpg unless you are only driving in city traffic?

 

Mr Green:

You are always so precise. Yes. I agree with your comments on working out mileage economy.

You remember VW had a tiny black plastic knob at the filler that you can press, enabling another extra liter of diesel to go into the tank? MB does not have it though in their diesel cars.

Yes. I have been doing city driving for the last 6 weeks. I love to go to Niagara Falls or somewhere to test it out.

 

Thanks. Eye tries!

My 2002 Jetta only had one for a very short time.
That plastic knob disappeared soon after my first fill up!
Known over on Freds' as a Ventecomy, it is the only way to fly.

See: http://forums.tdiclub.com/showthread.php?p=274521

Wish there was such a similar modification for the MBZs.

Are you using the "comfort" setting on your transmission?

Do you ease off slowly from rest in second gear and allow
your transmission to upshift as early as possible?

Perhaps if you try that, you will see even better fuel economy in town?
And mind you, 25 mpg is not too bad now, is it?
It is still rather cold up North, N'est pas?
Wait until you have a few thousand kilometers on the odometer and summer grade fuel!

 

Funny. I came across that TDI thing a long time ago and could not find it until you posted the link. The MB has a 80 liter tank so a full tank still goes further than a VW. Yes, I am using the C mode most of the time and I find it truly better (more economical, smoother shifting and nearly as fast as the S mode). I find the computer mileage readings too optimistic.

I try to use "Ultra" (Shell) or "Gold" (Sunoco) diesel but both contain Kerosene or some anti-freeze and is less powerful than summer fuel. There was a fire at a big Esso refinery in Ontario with an ensuing fuel shortage and price hike so I switched to ordinary, common gardener diesel. The last 2 months were brutally cold but the car is holding up well (parked outside, poor thing). The car came with a block heater installed but I have to buy a $100.00 cable and pay to get it hooked up. Typical MB - most items are sold as extras and costs over $100.00 each.

 

My best ever tank was 975 miles on my '03 TDI. Lots of guys go 800+.

Can you really go that far on 80l ?


Tim

 

We have winter and summer diesels in Canada. Winter diesel has kerosene or some anti-freeze like agents and less economical than summer diesel. It also gives less power than the summer stuff.

What size is your tank? 80 liters is a little over 20 US Gallons.

 

Using the vent trick (ie filling the expansion chamber) i think you can cram about 17.5 gallons in.

My 975 mile run used right at 16 gallons. It was a low-speed (60mph) all highway run. The car averaged 58mpg over 45k miles, so everything was "just right" plus I drove for economy.

Wish I still had it.

 

I did not know the 300 D is that economical. The best I did with my stick Jetta TDi was 50 mpg highway and it was a tiny car.

 

It's not. Tim is speaking about his '03 TDI.

From post number 7 here on this topic:

 

Mr. Green:

That is better. I thought my E is leaking diesel.

 

Yes, I was talking about my VW.

The best my 300SD has ever returned is 32.4mpg. My average is 31...but I have to drive like an 80 year old lady to get it...which I don't really mind. It is a game to me.

Just so long as I can stay out of folk's way, everything is cool.


Tim

 

I really liked the old VW TDi. I could have driven it like crazy and not affect the mileage by a couple of mpg. Those useless hybrids have to be driven with an eye on the computer to achieve the advertised mileage. Turbo diesels are much more superior too on the highway too. They are tougher as well.

Diesel! Diesel! Diesel!