Diesel Additives

[david7307]

Going to be doing an oil change and fuel filter change this weekend,and was wondering is it worth putting in a diese additive to clean injectors or is it just a waist of time, there is no smoke from exhaust, and if thy work what is a good one to use
thanks

[FisherX]

It really depends if your fuel system is dirty. If it isn't it will have no effect. If it is gummed up it might be good.

I remembering seeing a 5th Gear program on restoring power to older cars and the fuel system cleaner gave the best increase in power for five'r than anything else they did.

Anyway at $15 bucks it can't hurt.

[tangus89]

The best additive IMO is the Chemtec diesel power, not sure how much power it gives you (probably nothing) but keeps the algae from growing in your tank.

[Xtreme]

On a 23k km trip some years ago, I noticed the fuel consumption dropping off after about 7k km. After dosing with Nulon diesel injector cleaner, the consumption would improve significantly.
Since then I have been dosing every second or third fill, figuring that it's best to keep injectors performing well all the time.
I've only used the Nulon product so can't comment on the others.

[bsperka]

Going to be doing an oil change and fuel filter change this weekend,and was wondering is it worth putting in a diese additive to clean injectors or is it just a waist of time, there is no smoke from exhaust, and if thy work what is a good one to use
thanks

I use cleanpower (and other products) from costeffective.com.au. Per dose its cost effective (sigh) compared to other additives. (High initial cost). I believe fuel economy is better when I use it, but I don't record the data. Sorted out issues in an older diesel as well. Recommended to others who have had good results as well.

[onebob]

I dose every fill with a diesel additive but there have been periods where i didn't for one two or three tanks in row and my son (who's always following :p) say's it smokes less on the additive and cos i do record the fuel economy i can verify that the difference is 2 > 4 litres / 100k.

onebob

[discorevy]

I dose every fill with a diesel additive but there have been periods where i didn't for one two or three tanks in row and my son (who's always following :p) say's it smokes less on the additive and cos i do record the fuel economy i can verify that the difference is 2 > 4 litres / 100k.

onebob

Really ,onebob 2 > 4 litres /100k
So up to 1400 kilometers to a tank , what additive would that be?.:)

[DiscoDB]

The other alternative to adding your own additives is to run a tank or two of BP Ultimate Diesel every so often. I know specialist BMW and Audi Indies who swear by it in high tech turbo diesels and say you can see the difference when doing repairs with less carbon build up.

Do your own research and make up your own mind. If you are into adding additives, then going with the fuel companies mix can not do any harm.

I personally like to chase the lowest cost diesel (but no bio-diesel thanks), but if running low and passing BP then will get a tank of BP Ultimate Diesel. Again could be another form of Placebo......

[onebob]

Really ,onebob 2 > 4 litres /100k
So up to 1400 kilometers to a tank , what additive would that be?.:)

just commonly available additives - when i plug in the figures sometimes the calculator says 14.xxL/100kms (not good) and sometimes it says 10.xxL/100kms(excellent) and most times somewhere in between :)

[kelvo]

I personally like to chase the lowest cost diesel (but no bio-diesel thanks), but if running low and passing BP then will get a tank of BP Ultimate Diesel. Again could be another form of Placebo......

Your not far from cheap BP fuel.

BP in Waikiki are generally the same price or sometimes cheaper than Shell Coles or Woolworths Caltex even with their 4c discount.

[onebob]

Really ,onebob 2 > 4 litres /100k
So up to 1400 kilometers to a tank , what additive would that be?.:)

discorevy..... you do realise that 14l/100km is not 1400km per tank but 14L per 100km or 14L consumed to travel a distance of 100km...;)

[DiscoDB]

Your not far from cheap BP fuel.

BP in Waikiki are generally the same price or sometimes cheaper than Shell Coles or Woolworths Caltex even with their 4c discount.

...off topic, but the crazy thing is the next BP a few kms down the road can be 8-10cpl more expensive....

[discorevy]

discorevy..... you do realise that 14l/100km is not 1400km per tank but 14L per 100km or 14L consumed to travel a distance of 100km...;)

Yes onebob , I was just doing a quick Calculation based on my average hwy consumption (10.5 litres /hundred) from a brimmed tank (> 95 litres) works out to around 1400 kilometers....... BUT , only if using the additive used by yourself, which you say can give you up to 4 litres /hundred improvement, hence my inquiry as to which additive:D you didn't mention that you sometimes get 14 litres / hundred in your original post

[joel0407]

discorevy..... you do realise that 14l/100km is not 1400km per tank but 14L per 100km or 14L consumed to travel a distance of 100km...;)

I think/guessing he read your comment as 4L/100km not 4 litres less than normal/100km?

[discorevy]

I think/guessing he read your comment as 4L/100km not 4 litres less than normal/100km?

Actually did read it as 4 litres less than normal / 100km, which, when using my own figures (see above post) means a world beating ( for a disco) 6.5 litres / 100 kilometers

[kelvo]

...off topic, but the crazy thing is the next BP a few kms down the road can be 8-10cpl more expensive....

Both the Rockingham & Warnbro ones are a lot more, I think the Waikiki one is more of an independent.

[joel0407]

Actually did read it as 4 litres less than normal / 100km, which, when using my own figures (see above post) means a world beating ( for a disco) 6.5 litres / 100 kilometers

Well it depends a lot how and where you drive. Living in Darwin, we have a lot of 80km/h speed limits which means braking for traffic lights then accelerating to 80km/h frequenty. I find around town, myh fuel consumption can get to 15 - 16L/100km. Add a little slow off raod to that and I can get over 18L/100km. Then go for a drive out of town at 100km/h and it's back to 10.5L/100km.

I highly doubt that a fuel additive can make 2 - 4 L/100km difference. My confidence isn't helped when no specific additive was named as they all differ greatly.

https://www.aulro.com/afvb/images/imported/2016/02/168.jpg (http://www.fuelly.com/car/land_rover/discovery/2001/joel0407/200296)

[joel0407]

http://www.fuelly.com/car/land_rover/discovery/2001/joel0407/200296/fuelchart

I don't know if you guys can follow that link but it'll show how my fuel usage varies. I log every tank.

[joel0407]

The other alternative to adding your own additives is to run a tank or two of BP Ultimate Diesel every so often. I know specialist BMW and Audi Indies who swear by it in high tech turbo diesels and say you can see the difference when doing repairs with less carbon build up.

Do your own research and make up your own mind. If you are into adding additives, then going with the fuel companies mix can not do any harm.



I can't comment on the engine internals being cleaner but I know for fact that the premuim Caltax Diesel or Vortex as it's called, does nothing for fuel economy. I did 10,000km in my 2L diesel Skoda Yeti about 2 weeks ago. I did that in under 10 days and when I could, I filled with the premium Diesel. A few times I was able to fill multiple tanks of the premium in a row incase it was a prolonged use kind of change but still nothing. Again. I log every fuel up with km and fill the tank up the spout so I know exactly where its at.

Happy Days.

[CU55TM Disco]

Lol. U have a skoda.

[ramblingboy42]

I commend you for having a Skoda.

[joel0407]

Lol. U have a skoda.



Lol. I get more of a ****ling for having a Land Rover.


Just had a bit of a debate with my boss. She bought a new Prado which I like to tell her is just a HiLux wagon. My Skoda shares its mechanics with the Tiguan and Audi Q5. Same complete drive train. The debate started that I'm a bit OCD when it comes to cleaning cars. I told here I will keep my Skoda clean like the Audi it is underneath she can just clean hers like a work ute.

[onebob]

Actually did read it as 4 litres less than normal / 100km, which, when using my own figures (see above post) means a world beating ( for a disco) 6.5 litres / 100 kilometers

Sorry for the confusion folks caused by my initial "fuzzy" off the cuff reply.

I use either MORLEY's or CHEMTECH diesel additives.

onebob

[sierrafery]

Just add 0.5l of 2 stroke mineral oil to every full tank(actually it's 1/200 but 0.5/tank is approx the same), that's the best additive ever ;)... i was amazed what difference it made, i didnt notice consumption improvement but the engine definitely sounds better

[discorevy]

Just add 0.5l of 2 stroke mineral oil to every full tank(actually it's 1/200 but 0.5/tank is approx the same), that's the best additive ever ;)... i was amazed what difference it made, i didnt notice consumption improvement but the engine definitely sounds better

It couldn't possibly work any better than that new product invented by that dyslexic bloke bon deah , think the product is called nekas loi :D

[onebob]

It couldn't possibly work any better than that new product invented by that dyslexic bloke bon deah , think the product is called nekas loi :D

??:huh:

[discorevy]

Sorry onebob ,just playing with anagrams:)

[onebob]

Sorry onebob ,just playing with anagrams:)

..... maaate! i'm 62 next birthday and the ol' brain is running low on accessible RAM ;):D

[discorevy]

No worries, that dyslexic inventor was a bit of a nob head, his product was nothing more than snake oil :angel:

[joel0407]

****ling

It this an automatic forum thing or has a mod edit it for me?

I may have spelt it wrong using "ss" instead of "zz".

It's in the Macquarie Dictionary. I didn't think it was a bad word?:confused:

https://www.macquariedictionary.com.au/resources/aus/word/map/search/word/pizzling/Northern%20South%20Australia/

[joel0407]

Sorry for the confusion folks caused by my initial "fuzzy" off the cuff reply.

I use either MORLEY's or CHEMTECH diesel additives.

onebob


It's interesting that you get similar results with 2 very different products.

Plus one for the 2 stroke oil making the engine sound better. There is a mass of hype on the net and I'm doubtful of the credibility of some of it but there is such a mass amount it's hard to ignore.

Yes, I just use 2 stroke oil as my additive.

Happy Days

[Rick122]

Before adding 2 stroke to your diesel, consider reading the following. It's from South Africa but relevant.

http://www.fuelexpert.co.za/2-stroke-oil-in-diesel-technical-study.php

For those that don't want to read the whole document, here is the conclusion.

At a 200:1 volumetric blending ratio, 2-stroke oil has a negligible effect on diesel lubricity.
All diesel fuel sold in South Africa has to meet the SANS 342:2014 lubricity specification to ensure the proper protection of diesel fuel pumps and injector systems.
The low sulphur diesel products sold by Sasol contain lubricity improver additives which are far more effective than 2-stroke oil.
At a 200:1 volumetric blending ratio, 2-stroke oil has a negligible effect on diesel cetane number.
No measurable effect on all other regulated diesel properties was measured at a 200:1 dose of 2-stroke oil in diesel.
2-stroke oil can contain around 16ppm zinc, or higher depending on the formulation and batch.
Trace amounts of zinc in diesel are known to rapidly accelerate injector nozzle deposits.
Engine test results show that a 200:1 blend of 2-stroke oil in diesel results in a 2% loss of engine power in a 16 hour test due to injector fouling, a risk that would apply to any common rail diesel engine, but could also worsen fouling in older engines.
Vehicles fitted with a diesel particulate filter (DPF) in the exhaust system could experience reduced DPF life due to the collection of ash and metal based contaminants in the filter over time with the continued use of 2-stroke oil.

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[sierrafery]

Interesting, i've read it all, i can't argue with a scientific study, i dont even want to, IMO the gist of the whole article is in this statement: "The 2-stroke oils used in the study were also analysed for metal content and high levels of zinc and other metals were found in the oils tested." ... they should have clearely said what type of oil they tested though... cos that's why i highlighted mineral, cos at least all mineral 2 stroke oils i've seen(and put in the tank) were zinc free

[AndyG]

On the assumption that the Shell/BP/Caltex Chemical Engineers do a damn good job, and an additive may not be necessary in a clean engine, which Diesel is best, if any ? :confused:

[Rick122]

In regards to the zinc in two stroke oil, they used 2 mineral oils in their test and found trace elements of zinc in them. They didn't say if the oils were proclaiming to be "zinc free" or not but zinc is present in almost all mineral oils, its left over after the refining process. I don't think manufacturers would go out of their way to remove the zinc as it is a good thing to have in a 2 stroke engine and after all, that is its intended market use.

As for what diesel fuel to buy, before everyone jumps in and says "I always get x better economy from using y brand if diesel and my car runs like crap when I use z brand diesel", I'll just put this out there.
There are only 4 refineries in Australia, a caltex in QLD there's a bp in WA and the other 2 are Mobil and vitol in Vic. I've been to a refinery when I first did my fuel quality control lab course (now closed down) and have personally seen the trucks from different companies filling up from the same dispense point. Some then have their own additive bowser depending on what fuel they are taking on (ulp as well as diesel) which they use to dose the fuel they have just taken on. Eg. For premium fuel.
So most of the fuel from different companies comes from the same refinery.
In saying that more than 60% of Australia's diesel comes from Singapore, so no matter how close you are to a refinery you may not be "buying Australian". I would say that as the refineries are all in southern states, you are more likely to get fuel from one of those refineries if you live close to them and you are more likely to get fuel from Singapore if you live in the top end due to the cost if transport.

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[sierrafery]

There are many kind of 2 stroke oils, maybe using the unproper one would cause trouble, but those developped for 2 stroke diesel engines are zinc free and that's what i'm using, here's a list of how many kinds of 2 stroke oils are on the market: 2 - Stroke Oils | Products | Leboy Oil (http://www.leboyoil.co.za/p/653456/2--stroke-oils)

[Rick122]

The tests show that adding 2 stroke to the diesel had no positive effects with the possibility that over time it would be detrimental to the engine. I won't buy into the argument that you have to specifically use "zinc free" 2st to get the results. In fact most if the forums I have seen spruiking the benefits of adding 2 stroke only recommend a JASO FC spec oil which is 'low' zinc. If the 2 stroke oil you are using genuinely has zero zinc content then you may avoid blocking the injector nozzles compared to a higher zinc 2st but like I said, according to the tests it does nothing to improve the lubricity or fuel economy over straight pump diesel which is what most people are claiming.

Until someone does a proper test like this to show any benefit to adding 2 stroke to diesel, I won't use it. I'd much rather use a proper additive like chemtech.

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[DiscoDB]

There are only 4 refineries in Australia, a caltex in QLD there's a bp in WA and the other 2 are Mobil and vitol in Vic. I've been to a refinery when I first did my fuel quality control lab course (now closed down) and have personally seen the trucks from different companies filling up from the same dispense point. Some then have their own additive bowser depending on what fuel they are taking on (ulp as well as diesel) which they use to dose the fuel they have just taken on. Eg. For premium fuel.
So most of the fuel from different companies comes from the same refinery.


Rick - the important point is the fuel refineries can produce different blends to different specifications for different customers. It is the additives that some fuel companies add where the differentiation can take place even if the base stock comes from the same refinery (local or imported). And some fuel distributors add lower cost input components to sell a lower grade fuel at the same price which can result in engine damage in the worse situations. David.

[Rick122]

As far as i know, all the fuel sold here has to meet a certain specification. So as long as it meets or exceeds that specification (which is a lot higher than some other countries), we should be confident that the fuel we are putting in our tank is to a high standard. There should be no perceptible difference in quality between various companies fuel, especially given that a lot of companies use the exact same fuel. The additives are only for premium fuels not for plain old diesel.

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[DiscoDB]

As far as i know, all the fuel sold here has to meet a certain specification. So as long as it meets or exceeds that specification (which is a lot higher than some other countries), we should be confident that the fuel we are putting in our tank is to a high standard. There should be no perceptible difference in quality between various companies fuel, especially given that a lot of companies use the exact same fuel. The additives are only for premium fuels not for plain old diesel.

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I agree with the minimum quality specs. It is legal to add ethanol to petrol and to sell bio-diesel as long as they clearly label the fuel as such. But both Caltex and BP market a premium diesel which they both claim have additives - generally claimed to be cleaning additives, much like what people are buying and adding themselves. The Caltex and BP claim is this also reduces foaming when refuelling. I also have no doubt that both the Caltex and BP premium Diesel product is the same.

Now I agree that most of this is just clever marketing, but they must have some basis for the claims they are adding additives, and when I can often buy for the same price as regular diesel, the question is why add additives yourself when you can get it premixed for you to the fuel companies specifications.

[Rick122]

I agree with everything you just said. If I could buy such a thing as premium diesel here, and if it was cheaper than adding chemtech to my tank, then I'd buy it instead. However, the premium is not available everywhere in Australia so I'd still rather use the additive and plain diesel approach. I still don't know if you are agreeing that we shouldn't be putting 2 stroke in our diesel or if you are disagreeing that we shouldn't worry about which companies fuel we put in our tanks? :rolleyes:;)

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[DiscoDB]

I still don't know if you are agreeing that we shouldn't be putting 2 stroke in our diesel or if you are disagreeing that we shouldn't worry about which companies fuel we put in our tanks? :rolleyes:;)


No comment on the adding 2 stroke oil debate. Seems to be one of those topics that divides people with as many swearing by it as those who don't agree.

I would not worry about regular diesel bought from the major companies. Just be careful of the independents who have been known to blend in different sources, like bio-diesel, and cover themselves with a small label on the bowser telling you it "may have bio-diesel". No issue if you know what you are getting, and know what you want.

As far as the "premium" fuels debate goes, again seems to generate as much divided opinion. Having said that I have seen independent test which support there is a cleaning benefit and even a benefit of reduced fuel system corrosion, and depending on the state of the engine to start with, this cleaning benefit can restore performance or improve economy - even if the benefit is marginal and unmeasurable outside of a lab. Gets down to how much extra you are paying for any of the additive options.

And never underestimate the placebo effect. If you think you are getting better economy, chances are subconsciously you are adjusting your driving patterns and helping deliver this improvement. But now I have just gone off the deep end....heh heh...

One final comment, with the Td5 it probably does handle the most variable quality fuel you can get well. With my BMW 320d, I will only put the best in it - BMW even state must not use bio-diesel. With the TdV6 I am sure regular diesel is just fine.

[sierrafery]

Until someone does a proper test like this to show any benefit to adding 2 stroke to diesel, I won't use it. I'd much rather use a proper additive like chemtech.

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i completely agree with your attitude, i've started adding the 2 stroke(approx 150.000km ago) based only on several posts especially from UK forums(without any scientific backup) and i felt a kind of improvement myself, mainly in engine sound...though i'm regularly using a diesel treatment too which i presume is not very popular down under, this one Metabond Megasel diesel fuel additive shop for sale in Romania - Metabond Technology (http://wk111339250.company.weiku.com/item/Metabond-Megasel-diesel-fuel-additive-5427924.html)

[Mundy]

Yes onebob , I was just doing a quick Calculation based on my average hwy consumption (10.5 litres /hundred) from a brimmed tank (> 95 litres) works out to around 1400 kilometers.......

I am a little confused here. If you are getting 10.5L/100km and have a 95L (useable) tank then you will achieve around 905km not 1400km. To achieve 1400km you need to be getting around 6.8L/100km. I've never heard of someone achieving that at highway speeds.

[Xtreme]

I am a little confused here. If you are getting 10.5L/100km and have a 95L (useable) tank then you will achieve around 905km not 1400km. To achieve 1400km you need to be getting around 6.8L/100km. I've never heard of someone achieving that at highway speeds.

If statements by original posters were read in context there should be no confusion.
One bob stated that he was getting between 10 & 14 l/100km - a 4l/100km difference (improvement?).
No one said they were getting 1400kms from a 95l tank.

[discorevy]

I dose every fill with a diesel additive but there have been periods where i didn't for one two or three tanks in row and my son (who's always following :p) say's it smokes less on the additive and cos i do record the fuel economy i can verify that the difference is 2 > 4 litres / 100k.

onebob

Mundy , this was onebobs first post on this thread , so from this I calculated if the improvement was up to 4 litres per hundred, then based on my highway consumption (10.5 l/hundred) hypothetically would equate to 6.5 l/hundred ,so around 1400k range, now I know this isn't possible, therefore had a gentle dig

[ramblingboy42]

I'd love to know what I was getting as I 'cruised' down the M1 in the heavy rain last friday.

I was sitting back from the mad arabs at a steady 65kmh torque convertor locked up and just over 1200rpm on the tacho with about 3psi boost on.

Someone with scientific calculator and mind might work it out but it was significant on my fuel guage.

[discorevy]

Yes onebob , I was just doing a quick Calculation based on my average hwy consumption (10.5 litres /hundred) from a brimmed tank (> 95 litres) works out to around 1400 kilometers....... BUT , only if using the additive used by yourself, which you say can give you up to 4 litres /hundred improvement, hence my inquiry as to which additive:D you didn't mention that you sometimes get 14 litres / hundred in your original post

Mundy maybe you should have read the whole post rather than just pick out a bit so you can feign confusion

[rick130]

Bloody hell, how often does this get trawled over ? :(

And everyone has an opinion, this one is best, no this one, but how do you know ? ;)

My mates best friends cousin knows a bloke who posted on a forum that he categorically can state that the bloke at the loading dock at Castrol said...... :angel:

Have any of you done used oil analysis to see if the additive is reacting with the soft metals in the engine ?
I'm talking lead, tin aluminium, bronze,
There's this thing called blow-by, combustion gases make their way into the crankcase, this is why Caltex recommend that their famous Techron petrol additive only be used once or twice per oil change period.

Has anyone pulled an engine down and checked deposit levels, or the lack thereof ?

As already said by a number of posters, modern ULSD has to meet the Oz standard for lubricity, it's a wear metal scar, an actual measurement and is more stringent than during the pre high sulphur diesel days.

Nothing wrong with wanting a little extra protection, particularly for us running older mechanical VE style pumps that use the diesel as lubricant, but you are probably more likely to have a problem with seal/O ring shrinkage or water contamination than wear these days.

[schuy1]

As Rick said, more engines fuel systems are destroyed by filter neglect and contamination than by any actual fuel deficiency.
Cheers Scott

[rick130]

Now that I've upset everyone with my forthright views :angel:
Here's a set of pistons in a 300Tdi @ 325,000km. (we'll neglect the crack in #3 and the why's and wherefores at this stage)

http://www.aulro.com/afvb/attachment.php?attachmentid=93429&stc=1&d=1430617954

They've seen a reasonably regular maintenance dose of Redline RL2, since around the 100,000km mark, just to keep things clean and reduce the necessity of a premature pump overhaul
The throttle spindle is starting to weep now and there's possibly a leak from the high pressure section of the pump, just haven't isolated it yet, although it could be tracking from the top of the pump. (spindle)

In another lifetime I regularly performed used oil analysis, Redline 85Plus and RL2 (I'm guessing they are the same product, just aimed at different markets) was the only diesel additive I tested at the time that didn't show elevated bearing wear metals, and that includes BP Dieselgo, BP's own proprietary diesel cleaner/lubricant.

As for the mineral vs synthetic two stroke oil argument, where the hell does that come from ? It doesn't make sense ?

Redlines diesel additives use a POE oil as a pump and cylinder lubricant.

Polyolester, one of the highest flash point synthetic base lubricants, the same base as they use in their racing two stroke oils, so why the constant harping on forums "only use mineral oils" ?

Don't believe anything you read online, including this post. :D

Do your own research.

[Mundy]

I did read all the posts and I did not feign confusion. Thank you to those suggesting I'm either a cretinous moron or some form of stirrer.

[onebob]

It really depends if your fuel system is dirty. If it isn't it will have no effect. If it is gummed up it might be good.

Anyway at $15 bucks it can't hurt.

Yup! clean pipes are healthy pipes - my D2 gets Chemtech at the moment and I get Krill Oil :D each have their supporters and detractors.

that's life

onebob

[vnx205]

I have found that the factor that most influences my (perceived) economy from each tank of fuel is how quickly I become bored with continuing to dribble fuel into the tank as froth makes its way up the filler neck.

If I get bored quickly, it makes the economy from the previous tank look good and makes the next one look bad.

On the other hand if I have nothing better to do and continue to dribble those last half dozen litres in, then the economy from the previous tank doesn't look as good, but it helps the next one from appearing to be particularly bad.

The next most significant factor is the slope on the service station driveway that affects how well I can fill the tank.

Headwinds make a big difference. Having two kayaks on top of the camper while driving into a headwind makes an even bigger difference.

The only factor that I have never noticed having any significant, real impact on economy is the brand of fuel I buy.

I remain very sceptical about most people's claims about variation in economy from miracle additives; especially those who express their fuel consumption as the number of kilometres travelled before they decide to top up the tank. :p:p:p

[joel0407]

I have found that the factor that most influences my (perceived) economy from each tank of fuel is how quickly I become bored with continuing to dribble fuel into the tank as froth makes its way up the filler neck.

If I get bored quickly, it makes the economy from the previous tank look good and makes the next one look bad.

On the other hand if I have nothing better to do and continue to dribble those last half dozen litres in, then the economy from the previous tank doesn't look as good, but it helps the next one from appearing to be particularly bad.

The next most significant factor is the slope on the service station driveway that affects how well I can fill the tank.

Headwinds make a big difference. Having two kayaks on top of the camper while driving into a headwind makes an even bigger difference.

The only factor that I have never noticed having any significant, real impact on economy is the brand of fuel I buy.

I remain very sceptical about most people's claims about variation in economy from miracle additives; especially those who express their fuel consumption as the number of kilometres travelled before they decide to top up the tank. :p:p:p

Over 86 fuel ups. Recon I'm acurate as I can be with speedo being out a bit and trusing fuel stations.

https://www.aulro.com/afvb/images/imported/2016/02/168.jpg (http://www.fuelly.com/car/land_rover/discovery/2001/joel0407/200296)