[Roma]

I have treated my XF to at least two tankfuls of Shell V-Power Diesel since new. The cost has been eye-watering and totally defeats the point of buying a diesel-engined car! Yesterday I decided to try Shell Diesel Extra - this costs the same as regular Shell diesel. Since then i've driven the car around 150 miles and it seems to be much smoother, has more torque and generally feels livelier and better to drive. The engine also sounds a tad quieter.

Now, all this surprises me as Shell Diesel Extra is cheaper than V-Power. Which diesel are you guys using for the 2.7D XF? And has anyone else been surprised that paying the ridiculous amounts for the premium diesels is a bit of a rip-off?

Shell Diesel Extra contains all the same detergents as V-Power. I'll be sticking to Shell Diesel Extra from now on. It seems to hit the sweet spot with the XF's diesel engine. I'll know by the end of the week if my fuel economy has improved as I expect to do around 500 miles this week. As some of you will know, i've been very disappointed with the fuel economy of my XF so far and i'm wondering if this has been due to using Shell V-Power.

 

[garry]

I don't know if this helps but i once worked for a petroleum additives company and the general recommendation was to stick with one supplier of fuel as the addiitve mixtures can counter act fuel from different suplliers.