Fuel Consumption - rarely does one care in a 6.9, but.....

[AMG69]

...I decided as I was racking up around 300k's on the weekend in the 6.9, mainly south of Perth so highway kilometres, I'd take careful note and even went so far as to fill up at the same petrol station at the same pump (!)....so, I returned 15.6litres per 100 kilometres which according to the nifty converion table at

http://www.easysurf.cc/cnver4.htm

equates to 18.11 miles per Imperial Gallon or 15.08 miles per US gallon.  Fuel tank was filled and three of us on board - although jnr only weighs in at a hefty 15 kilos (   So a range of 608 from 95 litres (which realistically means I guess 544 km's per tank where a "tank" is 85 litres with 10 in reserve).  I was impressed.  My first V8, a 302 Cleveland Ford Fairmont XC used to get about 13.5l/100km's on the same drive so given the engine size and weight differential between the two I think thats about right. 

I vaguely recall Styria has achieved 20Miles per imperial gallon - which is 14.2l/100km's......thats very impressive but I suspect if I was by myself and had the cruise on 100 exactly that might be possible in my car.  Problem is I can never resist flattening it every now and then!

So, 6.9 owners how does that compare? I sat on between 100-110km/hr most of the time and was light footed once off the freeway.....

..oh, and US 300SDL drivers please dont ruin my day by telling me you achieve something silly like 11 l / 100km's as I just dont care.. 

[michaeld]

AMG69,
This is somewhat interesting, as I distinctly recall seeing the official mileage figure for the 6.9 listed as either (U.S.) 12 or 13 miles per gallon (and I believe it was 12).  That was for U.S. market 6.9s.  I suppose it's possible that the mileage would be better in cars w/o the smog eqpt, but I can't believe the difference would be that significant (and then, I'd like to know what the mileage of Australian market 6.9s was).

As engines age, they tend to get LESS mileage, not more.  It's not unusual for cars to lose 10% of their fuel efficiency or more.

I'd very much like to know what aftermarket gadget you guys installed to increase your mileage by over 25% from the day the thing rolled out of the factory.

I'm not trying to say that you guys have been smoking too much funny-weed to figure out your mileage, but this sure sounds like an interesting discussion...

Mike

P.S. Mind you, if you guys HAVE been smoking too much funny-weed to figure out your mileage, that's entirely your affair.  Back when I smoked the stuff, I just tended to laugh at nonesense and eat too much pizza.  I don't think I ever tried to calculate my mileage whilest subjecting myself to hallucinogens.

[AMG69]

OK, firstly, lets make sure we are comparing apples with apples - this was predominantly HIGHWAY mileage; I wonder if the Mercedes quoted figures are a combination of CITY and HIGHWAY?  As for Oz brochures and what these cars achieved new - Styria will answer that I'm sure; My car would get about 23l/100km's around town I know that!  As for modifications - mine has a K & N air filter and big bore exhaust (no Cats here in Oz back then); Otherwise stock standard! 

Will be interested to see some other Owners posts.....

cheers

Chris

[adamb]

On the 6.9 I've managed to consume between 9 (yes, nine  ) and 17 mpg (Imperial gallon). Averaging about 13. The W126 cars had much improved consumption. A 380SE from 1982 averaged 23 mpg during my ownership - going up to 30 when cruising at 60mph. W126 shows real refinement over W116 but are nowhere near as much fun. That's why I'll never swap the 6.9 for a 560SEL.

[AMG69]

Big Richard we need to plan a Perth 6.9 Owners run to Margaret River one weekend so we can REALLY enjoy these cars!

[robertd]

D'Day,
Not a lot of time to post, but interesting reading. I average around 17-18 MPG in the Euro 6.9. Curiously my 380SL doesn't get much better mileage than the bigger car.
Regards Robert

[adamb]

Hi AdamB, I am a little surprised at those figures that you have quoted for the 380 in particular, but as I have never owned one, I am in no position to come up with a direct comparison. It is very seldom that 126's compete in a Club's Economy Run which can generally be a good guide as to what consumption can be achieved by various models.

Hi Styria,

I was quite impressed with the 380. It was an early model that always started in 1st gear and had a more rev happy engine than what came a few months later. The figures did look too good to be true but that's what they were.

Cheers,
Adam