Protect your Diesel during the winter months

All Diesel in the UK must be manufactured to a British standard. These specifications contain seasonal requirements for summer and winter. A fuel certified for use during the summer period is only suitable for that period; winter fuel may be used all year. Summer grade fuel is produced during the months of April to the end of October with Winter grade fuel available for the 15th November to 31st March. 

So, what’s the difference, I hear you ask. Summer grade fuel will start to crystallise at -1 degrees, whereas winter grade doesn’t crystallise until -15.  

Potential problems of using the incorrect grade of gas oil in winter.

During cold periods, it is possible that there might be starting problems with diesel engines. It is even possible that an engine that is already running might stop. These problems are mainly due to the formation of wax crystals and condensation of water in the diesel fuel causing blocking of filters and pipes.

What can you do to avoid these problems?

  • Make sure that you have winter grade fuel.   
  • Add an anti-wax additive to the remaining summer grade fuel. This can only be added while the fuel temperature is above 13 degrees. It will not work if the fuel is already crystalized.   
  • Don’t mix winter and summer grade diesel as it will lower the temperature protection. By how much depends on the mix. 

This winter you may also want to protect your diesel from bugs 

With all diesels now having up to 7% biofuel, there is a strong risk that bugs could start to grow within your storage tanks. If this happens, you will have blocked filters on your machines, and this could be very expensive to fix. We recommend that you add anti bug additive to protect your fuel.

Or you might want to consider using 

Gas Oil Conditioner all-in-one treatment for Gas Oil. It will improve day to day running of diesel engines and will stabilise fuel during storage. 

Gas Oil Conditioner will raise cetane number to avoid rough running in newer engines, it will lubricate fuel pumps and lower deposit formation in injectors. 

Gas Oil Conditioner also contains stability additives and a biocide at a ‘protect’ level to keep fuel fresh when it is stored for long periods. Fuel will keep fresh for up to 2 years even when it contains up 7% biodiesel. 

The additive will counter any negative effects resulting from the introduction of the latest gas oil specifications, notably the reduction in sulphur content and the increase in the allowable FAME (biodiesel) content and will give improved fuel economy.  

Typical applications are agricultural and horticultural machinery, construction equipment, standby generators, airport vehicles and forklift trucks. 

The product is formulated from recognised fuel additive components and should not void an engine manufacturer’s warranty. In fact, very many engine manufacturers recognise the need for upgrade additives when red/ white diesel is used.

To find out more, contact our dedicated commercial team on 01476 584123 or email us at