All diesel has a package of additives included, fewer in the supermarket fuels allegedly. However, all fuel sold meets the relevant British Standard and is thus fit for purpose to the extent laid down by that standard

Notwithstanding TDIguy's possible association to United Diesel Fuel Injection Services Ltd, the firm I believe he is referring to as testimonial and also happens to be the firm who produces the stuff. I did a quick google around and came up with these "facts"

Millers ingredients:

• 2-ETHYLHEXYL NITRATE 50-70%
• COMPONENT 72248 30-50%
• D-LIMONENE <1%

Diesel Rhino ingredients:

• 2-ETHYLHEXYL NITRATE 40-50%
• 2-BUTOXYETHANOL 40-50%
• A MIXTURE OF ISOMERS OF: C7-C9 ALKYL 3-(3,5-DI-TRANS-BUTYL-4-HYDROXYPHENYL)PROPIONATE 1-10%
• NONYLPHENOL 1-10%
• ALKYL AMINES, MONOHEXYL AND DIHEXYL PHOSPHATES 1-10%

Shell V-power diesel's make up:

Complex mixture of hydrocarbons consisting of paraffins,
cycloparaffins, aromatic and olefinic hydrocarbons with carbon
numbers predominantly in the C9 to C25 range. May also
contain several additives at <0.1% v/v each. May contain
cetane improver (Ethyl Hexyl Nitrate) at <0.2% v/v.
May contain catalytically cracked oils in which polycyclic
aromatic compounds, mainly 3-ring but some 4- to 6-ring
species are present.

Note that all ETHYLHEXYL NITRATE as the cetane improver - higher cetane that leads to smoother running and for potentially better combustion.

I used to work for a fuel additives company many years ago, we ran field test vehicles to test the effectiveness of our additives. The additives were really effective at keeping injectors and inlet valves clean.

Mark.

The father of one of my son's school friends drives a Shell tanker. He says fuel comes out of the same tanks at the refinery or fuel depot be it it for Shell , Asda, Morrisons etc and that he sometimes delivers to supermarkets.

In a conversation I had a few years ago with a chap - I got to know him quite well - who was a driver for BP delivering from the ill-fated Buncefield depot in Hemel Hempstead, he quite clearly told me he had to add stuff to the contents of his tanker.

When it was put in (it could have been just before the tanker was filled) I don't know. Nor do I know if it was the same stuff that was added irrespective of the destination. Nor do I know where the stuff was kept - in/on the tanker or at the BP premises at the depot.

We do of course know that all fuel has some additives - it's not just "raw" petrol or "raw" diesel. The discussion is about what else is added to some fuels and whether it makes any difference.

Edited by FP on 08/04/2013 at 16:05

I can only tell it as I heard it.

"There's no way anything would be added so casually by the driver on arrival at the filling station." I didn't say that, and he didn't say that. For all I know, it was all done inside the depot.

The drivers sometimes added stuff at the depot while loading the tankers (from on top), this stopped in the1980s. Before working at height regs and H&S, they used to climb up a ladder at the back of the tanker and walk around on top, open 6-8 lids, one for each compartments and swing a hose round and fill each compartment as per the order and check level with dipsticks, they could then add red marker dye or whatever too. A few decades ago, it became forbidden to go on top and botto loading was introduced and you will see 8 or so faucets with caps on down one side (these were always there for delivering), but only 1990s- were they used for loading too. As loading has been a closed system for 30 years there is no way for drivers to manually add stuff. Bottom loading has been computeried for 20 years and additives are added from seperate small tanks for each customer at the depot, as you know, rationalisation in the late 1990s saw most depots close and the remaining ones shared bewteen different fuel companies and later supermarkets.