Comparison of brands of Petrol/Diesel - Big Dave
There seems to be a recurring debate as to whether there really is a benefit to the branded fuels recommended by HJ (Texaco & Shell) compared to supermarket fuel that many people use.

It would be very worthwhile for an organisation such as the AA, RAC or Consumers Association to conduct a thorough independent and scientific comparison of all available brands of fuel in terms of the fuel economy they deliver.

There are all sorts of claims that Shell fuel gives 5-10% more miles than generic supermarket. Given that fuel is sold by volume (litres), I presume there must be some quantifiable difference in these fuels in terms of density or energy content?

The current fuel market is all about brand image and reputation with no quantifiable consumer information to make an informed judgement.

Big Dave
Comparison of brands of Petrol/Diesel - googolplex
agreed!

Splodgeface
Comparison of brands of Petrol/Diesel - Morris Ox
Have you tried Which or What Car? I wouldn\'t be in the least bit surprised if they have already tackled this issue.
Comparison of brands of Petrol/Diesel - Shortwing Rob
Yes I\'d really like some clarification on this.

I\'m very sceptical about branding of commodity products and invariably buy my petrol where it is cheapest or most convenient - generally Tesco.

Brand promotion is what I do for a living and what Shell are doing is a textbook response to the problems caused to their independent garage purchasers by the supermarkets\' aggressive discounting.

However the other day I had cause to drop into a Shell station. Having read here about Optimax I thought \'Why not give it a try?\'

I\'ll tell you why.

It costs about 4p a litre more!!!

I\'m old enough to remember gallons and pounds / shillings / pence.

That\'s eight shillings a gallon EXTRA.

And for what? Some vague claim about more mileage? But you are paying more for it anyway, so what is the point?

Monitored scientific test would be a real bonus here I think.

Rob P
Comparison of brands of Petrol/Diesel - Shortwing Rob
Ooops. No it isn't. It's about four shillings a gallon extra. About the price of the first gallons of petrol I ever poured into my Ford Consul 375.

Oh lord, I'm turning into Victor Meldrew.

Rob

Comparison of brands of Petrol/Diesel - Mark (RLBS)
I do about 1000 miles a week, so a small increase in the price of a litre of petrol is quite significant, especially with a car which does about 3 lamposts to the gallon.

But I do find that the car feels better using Optimax or the Texaco super-unleaded and correspondingly just feels slightly rougher on normal unleaded. Whether that "feeling better" translates into any kind of better performance or better treatment of the engine, I couldn't say - especially since I keep no record of consumption; but it definitely feels smoother.
Comparison of brands of Petrol/Diesel - Mark (RLBS)
p.s. its closer to 3/6d difference.
Comparison of brands of Petrol/Diesel - Armitage Shanks{P}
I can remember when 3/6d wasn't the difference between two prices of a gallon but when it would have bought you a gallon and a Mars bar!
Comparison of brands of Petrol/Diesel - TrevP
please Miss, what's 3 and 6 mean?
Comparison of brands of Petrol/Diesel - Ian (Cape Town)
sheesh - 30-smothing years on, and they are STILL muttering about decimalisation ...
No wonder the EU gets upset with this pounds and ounces nonsense ... :)
[As johnny expat, I have the advantage [?] of speaking pounds/shillings/pence, stone, feet and inches, gallons quarts and pints (US and Imperial), yards, miles, furlongs, acres, thou's etc, as well as metres, kilo, kilometers, litres, millilitres, hectares, etc etc. Confusing? damn right ....]
Comparison of brands of Petrol/Diesel - Obsolete
please Miss, what's 3 and 6 mean?
It's the old temperature scale used before Celcius. Units are inches and ounces. Hope that helps.
Comparison of brands of Petrol/Diesel - DavidHM
Optimax aside, the Shell stations around here are about the cheapest - although because of the price of land, most of the supermarkets don't come with a petrol station attached.
Comparison of brands of Petrol/Diesel - Dave_TD
please Miss, what's 3 and 6 mean?
It's the old temperature scale used before Celcius. Units are inches
and ounces. Hope that helps.


I thought it was a bit colder today.
Comparison of brands of Petrol/Diesel - Peter D
Yes, done that over a winter and summer period (scottish winter )and as a result do not use Sainsburys or safeways fuel. but use Shell and BP 3p a litre more but it goes further 4.5% in the winter 6% summer. 18,000 a year over 2 year tests. regards Peter
Comparison of brands of Petrol/Diesel - Marc
I'm really annoyed because my local garage has just stopped being a Shell franchise and has switched to Murco "High Quality Fuels". The next nearest garage on my daily route is also a Murco.

This is not good as I feel both of our cars run sluggishly with Murco petrol. Or is it all psychological?
Comparison of brands of Petrol/Diesel - Marc
And another thing. Because of the supermarkets - have you noticed the massive decline in the number of petrol stations in a given town. Where I used to live (S Yorks) there used to be 5 stations within a 2 mile radius of home (Texaco, Esso x 2, Jet & Amoco. Now there is one Sainsburys and you always have to queue.

Not really progress is it
Comparison of brands of Petrol/Diesel - Shortwing Rob
So if my calculator is working right then 4% more cost gets you an average of 5.25% improvement in mileage.

Hmm.

As long as you don't have to drive out of your way to get to a Shell or BP station then over 18,000 miles at say 35 mpg on supermarket petrol you'll get 36.8 mpg on branded.

That's 25 gallons saved over the year, but 76% of the saving is then wiped out by the additional cost, so you can save the cost of about 6 gallons in a year.

My reading of that is to use whichever is most convenient.

Anyone else agree?

Rob P
Comparison of brands of Petrol/Diesel - Obsolete
I have kept a log of mpg for my Ka since purchase a year ago. I can't tell any difference between petrol brands, mainly because there are too many differences between runs. And the engine sounds a bit rough on any fuel. However I did notice a huge difference between Winter and other times of year. I was getting 45-48 mpg and then in Winter it dropped to 40mpg. I am now back up to 45-48mpg. Maybe this is due to the engine taking longer to warm up in Winter, whether warm air suits the engine better, or if there is less air resistance due to warmer and hence less dense air.

If a particular brand was demonstrably better for the engine, then I might pay a penny a gallon more. I don't know quite what better would mean though.
Comparison of brands of Petrol/Diesel - Daedalus
SWR

Got to go with you on this one.

Bill
Comparison of brands of Petrol/Diesel - Tim B.
Like others who responded, I find a difference between various brands of diesel.

Esso seems to make my Audi go furthest, and a little quicker and more smoothly. It also doesn't foam up as much as Shell or BP, so it is also a bit easier to fill. I steer clear of supermarket fuel.

I log all my fuel so I can claim back from the Tax man, and this observation is taken over 30,000miles winter and summer.

At one point I thought the car was playing up because the fuel economy had dipped noticeably, but when I went back to Esso all was well again. No idea why.

Cheers

TimBo
Comparison of brands of Petrol/Diesel - bafta
My Mazda definitely runs better on Esso petrol and I don't know why. So does my son's scooter. Both run on 95RON unleaded; mine's fuel injected and his is a two-stroke, so not much similarity there except we use the same grade. His, of course, gets mixed with oil but he still prefers Esso. I recognise that it all comes from the same refineries so it must be the additives.