I’ve been chatting with a workmate who’s got a 1.6tdci Focus Titanium X diesel like mine, his is a hatchback mines the estate, his a 62 plate on 165k mines a 61 plate on 111k, I bought mine a couple of months back and we decided to compare economy over time. I know mines heavier given it’s the estate but it’s done 54k less miles and has a full and upto date Ford history, his has no history at all and he said it’s not been serviced since he’s had it (2+ years) so I’d expect mine to be at least the same if not slightly better on fuel. He’s currently averaging 55mpg, I’m getting 48mpg - checked by brimming and dividing fuel added by miles covered since last refill rather than the optimistic fuel computer readings - we both do predominantly town driving (his OBC average speed is 20mph as is mine) I was puzzled by this, on talking further with him he said his was a lot worse on Supermarket fuels and he only gets good mpg from BP Ultimate, to be fair there is a sticker on the fuel filler saying Ford recommend BP fuels, I’ve been using Shell V Power diesel since I bought it (my old e38 was a good couple of MPG better on V Power petrol so I continued using Shell when I got this) The obvious answer is to switch to BP Ultimate and see if I notice any change which I suppose I’ll try I’m just surprised there is so much apparent difference between two supposedly premium fuels. Of course this is hugely subjective, he might have a wholly different driving style to me (I consistently better his trucks MPG in the office league table so doubt that) equally there may be some issue with mine that I’m unaware of. From what I recall my partners old 12 plate tdci Focus averaged around 55mpg also but fairly sure she put whatever fuel was available in and didn’t stick to any particular brand, she had a longer commute to work as well whereas mine rarely gets a run of any distance. TLDR - anybody noticed a variance between using Shell V Power and BP Ultimate diesel?