I've run oil burners for years, both here and in Europe and have never heard of the term 'cetane'. I've just looked it up.. I will say that I have alwas thought my cars did fractionally better MPG when running on French (or European) fuel, but that is purely subjective. I think the thing is that what you get at the pump is only ever rated as B7, maybe the 'super' varieties make a difference?. Redex, in my day, was only ever an upper cylinder lubricant and had no effect on octane or any other rating.. Maybe that is different as well, nowadays...

Just had a word with Neil on this subject. He says you shouldn’t use Redex in a Diesel engine. He’s never heard of Cetane so no help there. What you need is a petrochemical engineer. Having said all that we’ve been running our diesels on supermarket fuel since 2001 with no problems. Never had a clogged DPF either but maybe we’ve been lucky.

I’ve had 2 1/2 years of issues with the DPF on my Hyundai and it’s been back under warranty countless times. The warning light would come on at random times and the car would go into limp mode, often whilst towing, which is downright dangerous in my experience.

It was finally resolved (I hope) with a complete replacement of the exhaust and catalyser just before we set off to France in June. Before Hyundai would sign off this expensive replacement, they insisted on a fuel test to make sure it hadn’t been misfuelled or otherwise abused the car.


As I mostly use the car for work, and cover around 30,000 miles/year using pretty much all petrol brands including plenty of supermarkets, whatever is cheapest, I think this shows that all brands are ’safe’ to use.

The only thing I thought was thank god I didn’t try using bio-diesel!

Facebook groups including ‘’Kugas with caravans’ (no sniggering at the back please!) and ‘Ford Kuga owners club’ may be useful.
Also Cetane additives are available, search on Amazon.

Still regretting getting rid of our Kuga just 6 months before reverting to Eribas.
Lovely cars.

The problem with most supermarket fuels is that you're never quite sure who is supplying them. Personally, after DPF issues with a Volvo C30 2.0 diesel (Ford engine) that I owned from new in 2009, I virtually always fill up with only Shell or BP fuels. Volvo state that their diesel engines only need "standard" B7 fuel - and, indeed, warn against using "Super" type fuels. So, this is what I have done for the past 12 years and several hundred thousand miles in four diesel engined cars - with no DPF or emissions issues.

As a contrast to this, I used to own a 2002 mk4 Golf TDi that I loved. I used to put 25% rapeseed oil in with the diesel - and that ran perfectly, with no emissions or engine issues until I sold it. I stopped using rapeseed oil when bio diesel came in and the rapeseed oil became as expensive as diesel... Modern engines are too complex to do similar things with, although i do have a friend who invested in a processing plant (about £10,000) to make his own vehicle diesel from vegetable oil.

The Science:
Hexadecane (also called cetane) is an alkane hydrocarbon with the chemical formula C16H34. It is a naturally occurring compound in diesel fuel that ignites easily under compression. A purely cetane fuel would be rated at 100; a rating of 55 is seen as the highest "useable' rating, above which any gains in flammability would not benefit the engine (it would ignite too early). Below 48, the ignition of the fuel would be too delayed.

Here's an oil industry producer's thoughts on the question of additives to increase your car's cetane levels:

"There are several practical reasons for using cetane booster additives. These include:

Promoting diesel fuel efficiency by increasing the potential for every droplet sprayed into the combustion chamber to produce more power. This means your fuel will be burning for a longer time, allowing you to get more miles per gallon of fuel and thus, spend less on fuel.
Supporting smoother, more effortless, and faster combustion. The rapid startup and quicker ignition leads to fewer smoke emissions, primarily when used over a significant period. In addition, when fuel is burning more efficiently in the combustion chamber, the exhaust system is left with fewer byproducts to manage.
Giving diesel engines a great cold start by sparking up the ignition and enhancing their responsiveness.
Promoting the efficient distribution of lubricating liquids throughout the engine, reducing the components’ wear and tear. The improved combustion also produces fewer deposits, which ordinarily contribute to engine tear and wear.
Since a higher cetane number allows fuel to burn for longer, the pressure within the combustion chamber rises gradually, leading to minimal noise and less engine knock."

Must You Use Cetane Booster Additives To Obtain A Higher Cetane Number?

"There are two ways of obtaining a higher cetane number in your diesel fuel. The first one is during the refining process by hydro-treating the fuel. However, hydrogen is very scarce and expensive, which makes this process unfavourable. The second option involves using cetane booster additives. However, the challenge with most additives in the market is that they involve a lot of guesswork, making them inherently risky."