First of all, a few arithmetic games - because the test report lists some results in mg/kg, which in the scientific literature tend to be defined in ppm (parts per million):
1 percent = 102 = 10,000 ppm = 1 part per hundred = 1%
1 µg (microgram) = 0.001 mg = 0.000001 g
1 mg (milligram) = 0.001 g
1 g (gram) = 1000 mg
1 kg (kilogram) = 1000 g
1 ton (metric ton) = 1000 kg
i.e. 10,000 mg = 0.01 kilogram or 1 %
1) Statement by Auto Bild Klassik: " ... calcium and magnesium are supposed to keep the engine clean - but too much of it attacks the seals ..."
We at WAGNER Classic-Oil could not find any entry in the worldwide technical literature that would prove that calcium and / or magnesium can react negatively with sealing cords, felt, rubber, cork, plastic, metal or sealing paper.
2) Statement Auto Bild Klassik: " ... Zinc and phosphorus serve as wear protection. The following also applies here: Less is more for classic cars .... "
In reality, the absolute opposite is the case, because modern oils must NOT contain as many zinc and phosphorus-based anti-wear additives as they did in the days of classic cars!
Since 1935, ZDTP (zinc dithiophosphate) - zinc and phosphorus-based anti-wear additives have been added to engine oils. These are designed to adhere to the metal and ensure that the lubricating oil sticks to the metal for longer. In this way, these additives reduce the seizing friction of metal on metal during cold starts as well as in the event of short-term lubricating film breakage.
For the sake of the catalytic converter, a constant reduction of these classic ZDTP wear reducers has been taking place in modern engine oils since 1990.
So if WAGNER Classic-Oil has a high proportion of classic wear protection additives based on zinc and phosphorus, this speaks precisely for a good classic car oil. Because classic cars absolutely need zinc and phosphorus-based wear protection.
3) Statement by Auto Bild Klassik: " ... sulphur reduces friction, but produces sulphur dioxide during combustion, which accumulates as acid in the oil ... "
This statement is factually correct and not objectionable. However, why the two oils with the highest sulphur content were chosen as test winners will probably remain the editor's secret forever.
According to the test report, the sulphur content in WAGNER Classic-Oill 20W/50 HD oil is 3,235 mg/kg = 0.3 % of the total mass. The standard value of sulphur in modern engine oils is 0.5% to 1.8%.
WAGNER Classic-Oil can therefore be described as low in sulphur.
Why does WAGNER formulate the engine oil for classic cars to be low in sulphur? Because sulphur in high concentrations can attack soft metals such as bearing bronze, white metal bearings or non-ferrous metals such as copper and brass. And because sulphur - as correctly pointed out in the article - produces sulphur dioxide during combustion, which forms acids in the oil bath.
THIS IS WHY WAGNER Classic-Oil is one of the lowest sulphur engine oils on the market.
4) A side note: Incidentally, the sulphur content is equated with the BN number in the test evaluation table in Auto Bild Klassik. This is of course incorrect. The bracket (BN figure) belongs to the alkaline reserve - one line below ;-)
5) In the text, the editor translates "BN (Base Number)" as "acid number". This is luridly worded nonsense. The BN or TBN (Total Base Number) is of course the base number - not the acid number. Auto Bild Klassik just pretends that the base is the devil - in turn, the acid should be the saving angel ... ;-)
However, this style fits very well with the first two paragraphs of this article ... And also with the conclusion drawn. Not substantiated with anything - but formulated in a populist, sensationalist way. Just a picture newspaper for classic car enthusiasts ....
6) Incidentally, the article makes several references to the TBN (Total Base Number) - which seems to have been particularly important to the editor. Why is completely unclear to us at WAGNER Oldieoel.
Since the subject is a little more complicated, let's start with a little theory:
A base is the opposite of an acid. Acids neutralize bases - and bases neutralize acids. Bases increase the pH value of a liquid - acids lower it.
In other words: EVERY liquid is always either an acidic or a basic (alkaline) liquid. There is no liquid that is neither.
Water, for example, has a pH value between 6 and 10, whereby values up to 6 are considered acidic (acid), values around 7 are considered neutral and values above 8 are considered alkaline liquids (base).
Now to the practice:
Engine oil MUST be alkaline in order to neutralize acid inputs in the oil. If the oil could not neutralize the acid inputs, metals and seals would be attacked and destroyed by the acids.
Much worse than the natural ageing and self-oxidation of the oil are condensation water and, above all, unburned or partially carbureted fuel components that get past the piston and into the engine oil. It is certainly obvious that this problem occurs much more frequently in a classic car than in a new vehicle. The greater tolerances of pistons and piston rings, the condition of old oil scraper rings and hardened valve seals etc. pp. - Almost all components on a vintage engine cannot seal the oil circuit nearly as well against fuel ingress as is the case with modern engines.
Fuel deposits often consist of strong acids - or they quickly form such acids in reaction with condensation water and / or engine oil. For this reason, the engine oil has a supply of bases. The base in the supply neutralizes the acids and thus successfully prevents corrosion and wear-causing contamination of the engine oil. As with all acid-base reactions, the base supply is gradually used up during the acid neutralization process.
It therefore makes sense to add a sufficient supply of bases to the fresh oil. At 9.75 mg potassium hydroxide (koh) / gram, the base stock in WAGNER Classic-Oil is high, but not excessive.
It takes into account the fact that
a. there is much more acid input in classic cars than in modern vehicles
b. the engine oil in classic cars is not run hot every day to evaporate water and pollutants
c. classic cars are often parked for long periods of time and non-neutralized acids would cause devastating damage during these downtimes
d. contrary to all advice, some classic car owners tend to delay oil changes - often the engine oil is only changed every 2 years
e. also contrary to all advice, many classic cars use engine oil that is far too viscous out of a misguided interest in oil pressure
So it is by no means a mistake or an oversight when WAGNER adds a high supply of bases to its classic oil. And with the best will in the world we cannot see where and why this high base protection should pose a risk to seals? Apart from nylon, no plastic reacts negatively to alkaline liquids; sealing cords, felt, rubber, cork, metal and sealing paper certainly do not.
7) The article mentions "six milligrams of KOH (potassium hydroxide) per gram of oil" as the absolute limit value for the BN figure - this figure is simply made up out of thin air.
After 15 years of dealing with the subject of engine oil for classic cars, we at WAGNER Classic-Oil have a very good overview of the worldwide literature on the subject. And that includes antiquarian AND modern literature. No serious scientist has ever determined or published such a limit value. And - for the reasons mentioned above - it would make no sense. When asked, the editors of Auto Bild Klassik were also unable to present us with any scientific basis for their theses and assumptions ...
8) We would also like to mention the subject of impurities. Silicon, for example, is contained in anti-foam additives - and these in turn have been used in engine oil since the 1920s to prevent the oil pump from sucking in hot oil foam instead of fresh, cool engine oil. It is in the nature of the chosen test procedure that such intentional, "positive contamination" cannot be distinguished from unintentional, genuine dirt.
Real oil tests are therefore very, very complex and correspondingly expensive. However, trying to glean such far-reaching findings and results from simple oil analyses, as Auto Bild Klassik attempted to do in the much-discussed "oil test", does not work. Especially not if you then also start from false theses and arbitrary assumptions.
We at WAGNER Classic-Oil deliberately did not react immediately to the "test report", but asked Auto Bild Klassik to comment on our critical questions.
We implied that we were not immune to being blinded by the company.
And asked whether Auto Bild Klassik had any new, scientific findings that had perhaps not yet reached us here in Swabia?
And we asked Auto Bild Klassik to justify their theses and assumptions.
Unfortunately, the editors of Auto Bild Klassik were unable to do so. They insisted that these technical questions were only of interest to experts - and that laypeople would not be able to follow them anyway.
We therefore feel compelled to publish our rebuttal here. We hope that we have been able to explain our view of things to you - regardless of whether you are an expert or a layperson.
