Yetijames, although I retired early this year, I've been teching, designing and developing diesel engines (predominantly), for 33 years. During that time we found a huge difference between the different brands of fuel, especially for diesel. This difference continues to day but that difference has narrowed a little. Supermarket fuel (diesel) has a few more proper cleaners in it now over what it used to have. Importantly, it also has additives that lubricated the high pressure pump in your car much better too and it's pretty much inline with other more branded stuff. Previously the lubrication properties of some supermarket diesel was inferior to the better known branded products such as Shell, Esso, Texaco etc. The added cleaners were also considerably inferior. But as said that has improved now and it needed to. During the mid to late 90's the supermarket fuel was so bad that many of the big car and truck manufacturers were forming a group to take Tesco and some others to court over the quality of their fuels. The reason for this was down to early high pressure pump failure caused by insufficient lubrication from the diesel fuel. Diesel pumps rely on the diesel fuel itself to lubricate the bearings inside the pump. Fuel pumps cost massive amounts of money (£1000's in many cases) for diesels and many pumps were failing during warranty and it was down to insufficient lubrication from supermarket fuel. There have been many tests carried out over recent years and supermarket fuel in the main, is still not as good as the branded stuff. You get fewer miles per gallon and less power (as per Top Gear, Fifth Gear testing) and the engines still burn less cleanly which can cause early failure of some engine components. This may not matter to many if you are not keeping the car for long. Some supermarket petrol such as Tesco's 99ron is more than ok but most cars don't need it as they are designed for lower ron petrol. Diesel, well I personally always use Shell or Esso. Although Esso is now part owned by Tesco, they use their own brand of fuels still so it's completely safe and delivers on performance. 

Estateman,

Many thanks for your well informed response.

I shall follow suit :0)

Cheers

Just don't use morrissons diesel. It's a bio diesel and vag group Diesel engines really don't like it

 

 

So is pretty much all diesel

I know tesco's also have upto 8% bio

Its that minute that it makes zero difference to the car

Ran tesco's diesel which includes bio in all my derv cars and work vans over the past 10 years without issue

 

I'd echo what brianpilman has said ref Morrisons fuel, in my experience.

 

I had an 07 plate Octavia which suffered from a mild misfire at around 1200-1500 rpm, it was noticeable. The independent VAG specialist and main dealer both agreed that the issue was the fuel I was using at the time. My fuel card restricted us to where we could fill up - Morrisons was the easiest and closest. Once I made the switch to a different fuel, the issue cleared.

 

Whilst I appreciate what Big Jase is saying ref minute levels of additives, in this case, it did make a difference. 

all diesel sold in the uk has a percentage of biodiesel (think its upto 8%)

and it doesnt matter to your car

100% biodiesel then yes you have a problem

Sure about that?

Biodiesel was just the topic on a show about consumer rights on TV2 here in Norway.

And they interviewed some mechanics, got statements from Toyota (if I recall correctly) and a professor from NTNU. They all stated that the 7% Biodiesel was a significant source of problems with dieselcars in Norway.

I dont know if the cold Norwegian winters can play a part, but it was DPF-problems, injectors sooting/getting clogged and that sort of problems.

Thr program is called "TV2 hjelper deg" and was aired thursday 6. of Febuary. Sadly there is no free streaming available.

Edited 8 February, 201511 yr by Gromle

I use my local Shell for fill-ups, Its only 1p per litre more than all the local supermarkets, but its a lot closer, so my usual £30 a week fill up costs me approx 26p more each week at current prices........... surely a no brainer?

 

:clap:

I too have noticed economy drops on Morrisons diesel. Not noticed any running problems though.

 

The Shell garage on my way home is usually the same price as Morrisons due to proximity, so it's a no brainer. If I need fuel at home or on my way to the motorway I use Harvest Energy standard diesel.