Fuel and Quality

[MY300]

Petrol are we getting what we pay for?
My routine of filling up my work van and 300C are the same i fill up and set trip meter and basicalliy go by this to see when my next fill is coming up by the kilometers travelled.I have been filling up at the same station for quite a while.
Have had my 300C for 1 month now and my first two fills i was getting 19.5l /100k's and not the recomended ..new car .. ok ..still running in etc.. no probs.
Then on my work van a Mercedes MB100 petrol all of a sudden the last two fills i got about 80 km less in the tankfull...well something not right here so ...
300C 19.5l/100
mb100 travelling 80 km less/tankfull is my gauge faulty tune incorrect???? not happy jan...

Changed to another brand and voilla all went back to reasonable figures
300C 15.4/100 city driving ...good
mb100 back to getting my 450 km per tank...

So whats going on... the service station i was filling up at i had no problems before only when these fuel price rises have steadilly been going up.I have also been using this brand most of my driving years. So now they have lost me.
My question is has any one else noticed this kind of thing recently and what brand of fuel and octane should we use with confidence and get our dollars worth per litre..I am not complaining about the cost as we are all in the same boat .I just want to get what I pay for...

My brother runs a service station in Pakenham just out of Melbourne.He has Caltex Fuel and no additives at all.There account customers swear by their fuel especially their Diesel as their figures show great economy. I ran all this by him ,as the staion I was filling up at was a Caltex station..he just shrugged his shoulders and basically had no explanation but to say he knows what goes into his tanks...so what do you do????

[stevesrt8]

you have touched on why I monitor my mileage so closely.

Gasoline varies greatly from pump to pump. I'm not sure about UK requirements but over here in the US I try to only buy from Top Tier sellers. They are listed online. Chevron and Shell are two compliant retailers.

Read more @ http://www.sigma.org/meetings/handou...TIERslides.pdf

[dnar]

I have heard stories of fuel companies adding liquid butane at the refinery to raise RON before it leaves (to pass testing). Unfortunately, if this is true, butane evaporates out in the servo tanks.