Diesel vs Premium Diesel

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BlindFreddie

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Ever since bacteria was found in a tank of diesel (or the water in diesel would go on) in my old 405SRDT years ago I have been very careful where I buy my diesel from.

Currently I am running a 308 T9 Hdi and am concerned after reading conflicting reports on whether to stay away from premium diesel because of the damage the additives might cause. Others say the additives are just a harmless cheap marketing gimmick to extract more money from gullible motorists.

Both types of diesel I have been told have the same calorific value.

Appreciate your thoughts
 
It's a marketing gimmick. Diesel fuel specifications are the subject of Commonwealth law. Any thing extra is a detergent or the like. There is no difference in the hydrocarbon fuel. I have had diesels since 1970 and have never bought anything other than standard, and have never suffered a fuel related problem.

Water is a separate and serious problem, as it permits a nasty black growth in the tank that clogs up engine components. Biocides are available, but it's a good plan to stay away from low turnover places, particularly when the underground tank is low (which you don't know). The "premium" product is not a biocide.

Trivial amounts of water get in from condensation and the like, and the fuel filter has a water trap and drain, which should be checked at service time.
 
Hi.

I agree with seasink.

I was at a mining trade show once and a major fuel supplier had a stand. I spoke to a rep and pushed to get him to disclose what the differences were from usual diesel and premium diesel. After peddling me with all the usual stuff in the advertising, the only thing he mentioned was that the premium diesel had more/better defoamers, so that it was easier to fill the vehicle tank. The marketers can put a spin on anything.

Same calorfiic value, same cetane rating, I used to use the everyday diesel and keep my money in my pocket.

Cheers.
 
Premium diesel, as others implied, is marketing w@nk. In a similar vein to the other bull they peddle about X product keeping the inside of your engine clean.

On both our C5s and previously the (Aussie) C4 we noticed zero difference in regular or premium diesel fuel. The only difference was the price. Unless I have no other option I will buy regular diesel every time.
 
Its the same story with premium 98 petrol - there are mandated standards for 91 and 95 octane, but not for 98.

So 98 only needs to meet the standard of 95, and in reality you'd be lucky to get more that 96-97 because they'll just mix it in with 95 if theyre low on 98 - assuming its 98 they make anyway.

What you're paying for when buying 98 is a lot of marketing and some unproven additives.
 
Hi.

What really gets me going is that the clever marketers by introducing new names to differentiate products, we are all left with not much choice than to say the words "standard" or "premium" diesel, and so perpetuate to others a difference that is not there. The additive packs will be very similar for "common" and "marketed" (my new words) diesel, maybe with a few tweaks so that if pushed they could say there is a "difference"

Same with petrol, and I have posted previously that marketers love numbers, and a bigger number is always better. There are many people that use premium 98 RON in engines that only need 91, its an emotional purchase. The fuel industry is laughing all the way to the bank.

Cheers.
 
Haakon said:
Its the same story with premium 98 petrol - there are mandated standards for 91 and 95 octane, but not for 98.

So 98 only needs to meet the standard of 95, and in reality you'd be lucky to get more that 96-97 because they'll just mix it in with 95 if theyre low on 98 - assuming its 98 they make anyway.

What you're paying for when buying 98 is a lot of marketing and some unproven additives.
Click to expand...
Hi.

You are correct, 98 RON only has to meet 95 RON standard.


And here is the reference from: https://www.dcceew.gov.au/climate-change/emissions-reduction/regulating-fuel-quality

1678149353013.png


Cheers.
 
Whippet said:
Hi.

What really gets me going is that the clever marketers by introducing new names to differentiate products, we are all left with not much choice than to say the words "standard" or "premium" diesel, and so perpetuate to others a difference that is not there. The additive packs will be very similar for "common" and "marketed" (my new words) diesel, maybe with a few tweaks so that if pushed they could say there is a "difference"

Same with petrol, and I have posted previously that marketers love numbers, and a bigger number is always better. There are many people that use premium 98 RON in engines that only need 91, its an emotional purchase. The fuel industry is laughing all the way to the bank.

Cheers.
Click to expand...
Some cars even run worse on 98, whereas most will just run no better. Reno Clio Sport 3 is famous for being a pig when cold on 98, and is perfect on 95 (you know, the fuel the factory tuned it for!).

I know a bloke who worked on a project doing fuel sampling and tests on retail fuel outlet as part of his job with fuel quality standards in Canberra. None of the 98 samples tested as 98, most we around 96.
 
I was disgusted to see signs on Caltex pumps asking "How much do you love your car?"
It's clear guidance was that if you truly care for your car you will always buy the most expensive fuel 😡
 
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Yeah my wife trys the "how much do you love me" thing too with Pandora ads.🤦‍♂️
 
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My petrol Berlingo is meant to run on a minimum 95. I run it on E10. Twice I have filled it with 98 and there has been zero difference to performance or economy.
 
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well yes .i was disappointed at the size of a large pizza ,then i found that if i had wanted large, i should have ordered extra large . go figure ?
 
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It looks like the old adage, " You get what you pay for" doesn't apply to fuel. Good to know the difference between diesel.
Our RS Clio 200 N/A allows a choice between 95 and 98.
The Lancer Evo insists on 98. Our (now gone) Xantia CT turbo used to ping under load with less than 95 RON. That is why I now always use 98 in the cars ( pre-ignition in an EVO would be a time bomb). I am so paranoid about the mandated practice of E10 being added to 91 and 95 to increase RON that I use 98 in all cars, motorbikes, mower etc. What I do think is that 98 might be slower to loose its octane over time. Our motocross friends wax on about the importance of fresh fuel to get maximum bang in competition.
Many of our machines are unused for long periods (months not years). Stale fuel has never been a problem with 98.
My question is, even if the RON of 95 and 98 is the same, are there other benefits of 98?
 
Looks like a potential case for the ACCC, if no scientific evidence to justify the higher cost of 98. Fuel companies conspiring to gouge motorists.
 
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