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Fuel Economy

Started by PMcG, 15 March 2021, 11:24 PM

PMcG

I know it's a bit of a joke with these (non-diesel) cars, but out of curiosity, what are most of you getting mpg-wise?

After driving my 450SE 6,000 miles, I've found it stays between 12-16 mpg, using non-ethanol 92 exclusively.

Is there a speed at which this car does best for gas mileage?
1976 450 SE
Diamond Blue Metallic / Navy Blue

daantjie

With the 6.9 you are lucky to get 8-10 mpg in town.  Freeway about 12-14.
Daniel
1977 450 SEL 6.9 - Astralsilber

ptashek

#2
Euro 450SE, over the last 25k miles:

- best: 12.35 litres/100km ( 19mpg US / 22.9mpg imperial )
- average: 16.3 ( 14.4 / 17.3 )
- max: 16.8 ( 14 / 16.8 )

There's far worse figures on a few occasions, but they're mostly over very short runs, or when waking the car up after its winter slumber.

When driving long distance on ethanol free 98RON she usually stays above 16mpg US.
At top speed on the Autobahn it's below 8mpg US :D
1993 "Pearl Blue" W124 280TE
1988 "Arctic White" W124 200T
1979 "Icon Gold" W116 450SE

adamb

my 6.9 - worst 9 mpg imperial, best 16 mpg imperial. Averages 15-16 in my use.

Nabstud

My 280S (2.8L 6cyl carby) averages 15mpg(15.5L/100km), highway or city doesn't seem to change much. Worst I ever got was 13mpg (19.5L/100km), best is 16.5mpg (14.2L/100km).
1975 280S - Australian delivered

Mick74

I averaged a heady 17.6mpg (14.5 US) over my 3000 mile European trip in 2019 with 4 people and luggage on board. That was on 98 octane, though. It is usually aroung 16mpg (13.2 US) but does improve slightly on a run. Although, the last 244 miles, comprising of 7 miles to town and 7 miles back (under covid lockdown) saw an average of 14.2 mpg (11.7 US).
The best I have seen so far on one tank is 18.2mpg (15 US)
1979 6.9 #6475

Mattr

My 450SE 6.9 gets 8mpg. There's no range.

My 450SEL 6.9 got 14mpg cruising around, when I drove it last, and the guy I bought it from swore he averaged 16 everywhere.

Those're US gallons, btw. No British galloons here.
1976 450SE 6.9 FrankenBenz (#2288?)
1977 450SEL 6.9 #2333

BCDC

My advice is don't worry about it. I get around 15L/100km using 98 octane here in Australia. Slightly better on long runs. These cars are heavy so "milage" is irrelevant. They feel the same at 160km/h as 60km/h. There is no point pussy footing around with this car, they love to rev so drive it like you want. This is exactly why they have 96 litre fuel tanks. Enjoy and pretend you don't care about the money.
1978 280SE Cream with blue interior. With SLS

Nabstud

Quote from: BCDC on 24 March 2021, 12:35 AM
My advice is don't worry about it. I get around 15L/100km using 98 octane here in Australia. Slightly better on long runs. These cars are heavy so "milage" is irrelevant. They feel the same at 160km/h as 60km/h. There is no point pussy footing around with this car, they love to rev so drive it like you want. This is exactly why they have 96 litre fuel tanks. Enjoy and pretend you don't care about the money.

Spoken like a true car enthusiast 👍👍👍
1975 280S - Australian delivered

BenzTragic

Quote from: BCDC on 24 March 2021, 12:35 AMMy advice is don't worry about it. I get around 15L/100km using 98 octane here in Australia. Slightly better on long runs. These cars are heavy so "milage" is irrelevant. They feel the same at 160km/h as 60km/h. There is no point pussy footing around with this car, they love to rev so drive it like you want. This is exactly why they have 96 litre fuel tanks. Enjoy and pretend you don't care about the money.

Great advice and exactly what my indy mechanic tells me. I've just had my fuel head rebuilt (again...) and a few others things sorted within the fuel system. I just measured mine and got 16.9L/100km.
Current Mercedes
1977 W116 450SE
1988 W126 300SE
2001 W220 S430

Past Mercedes
1982 380SEL
1985 280SE

raueda1

Quote from: daantjie on 15 March 2021, 11:40 PMWith the 6.9 you are lucky to get 8-10 mpg in town.  Freeway about 12-14.
Basically this ^ what Daniel said though I actually seem to do a little better around town.  But maybe he engages the full 6.9 effect more than I do.  Best I ever did on the highway was 15 mpg.  That was with a tailwind and constant-but-gentle continental downslope from Colorado to Iowa.
-Dave
Now:  1976 6.9 Euro, 2015 GL550
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

UTn_boy

If you have a U.S. version 450se it'll have a low compression engine.....somewhere around 8.00:1.  The U.S. versions take regular unleaded 87 octane.
1966 250se coupe`,black/dark green leather
1970 600 midnight blue/parchment leather
1971 300sel 6.3,papyrus white/dark red leather
1975 450se, pine green metallic/green leather
1973 300sel 4.5,silver blue metallic/blue leather
1979 450sel 516 red/bamboo

Type17

Over the last 7,200 miles / 10 years, my 350SE has averaged 17 MPG Imp. / 14.1 MPG US / 16.6 l/100km

Best was 22.5 Imp. / 18.7 US / 12.55 l/100km - a Mercedes-Benz Club run on quiet highways at around 80-90km/h / 50-55mph

Worst was 13.2 Imp. / 11 US / 21.4 l/100km - a half-tank where I consistently got stuck in heavy city traffic.

PS: If you have an iPhone, I recommend the Road Trip app - great for logging fuel, servicing and other expenses (no connection with it, just a happy user). I've logged all my cars since 2012 - https://darrensoft.ca/roadtrip/
'76 350SE in Silver-Green

goldacre

My 1979 450SEL (4.5 ltr) low compression Australian delived car on its best run was 13.1 litres per 100 klm on a 45 degrees Celsius day (damn hot) AC on and cruising at 100kph and was very happy with that.

On other runs where traffic driving, freeways etc it ranges from 14 liters to 18 liters per 100klm.

I find using the low octane fuel which is reported to be 91 octane increases consumption by 1 ltr per 100klm from experience but do run hi octane at 98 on long trips when weather is hot but have been told would need to tweak engine timing to get full benefit? Slightly more advanced apparently?

G
12/1979 450 SEL 148K on clock (museum piece)
12/1986 Lotus Esprit Turbo 87K on clock 'Darling, look what Q has brought for us, isn't it nice' :)

adamb

My 1977 6.9 with the standard engine - best 17 miles per imperial gallon, worst 9 mpg. Averages 13-14 mpg. For the record, my main family transport is an electric Dutch "Mama Fiets" with two child seats.