It may surprise you to learn that many diesel additives, including well-known brands, are still using mono fatty acid lubricants in their diesel additives.
Why is this an issue? Not only is fatty acid very old and cheap technology, but it offers zero lubrication benefit to UK or EU EN590 specification diesel, where the minimum ASTM D975 wear scar test is 460 µm. Mono fatty acids are designed to reach this level but not improve on it.
But it is worse than this. Many diesel additives utilize 2-EHN to raise the cetane level to improve combustion quality and torque output. However, mono fatty acids do not work in the presence of 2-EHN. They cancel one another out, resulting in no HFRR improvement. In some instances, lubrication is worse than it was before using the diesel additive, and customers are completely unaware that they are using a diesel fuel additive with inferior lubricity. This includes established brands from the UK, Germany, and beyond. They sell thousands of products daily, mostly through platforms like Amazon. Customers rave about them and leave great reviews without any idea that they are simply buying a diluted 2-EHN cetane improver with a cheap lubricant. And possibly in a fancy-spouted bottle, depending on the brand. Seriously, most of them don’t even use detergents. These products are manufactured at under £2 and then sold to you for £13+ for 500ml.
Any diesel additive with a little 2-EHN will improve performance, so it must be a great product, right? What about what you can’t see, such as the lubrication and protection, cleaning, and so on? As a consumer, it is important to understand what is in the diesel additive you are putting in your engine.
This is where Ester lubrication comes in. Certain ester technologies do perform in the presence of 2-EHN. They complement each other perfectly and are much more likely to deliver an improved HFRR response. At the very least, 2-EHN based diesel additives with ester will not lower lubricity.
There are still limitations with esters though. And that is when used with summer specification diesel. This is because high-quality summer diesel is usually much more lubricious than the standard 460um limit, and even ester lubricants struggle to provide an advantage in these fuels. This is where Orisyn Ester enters the party. It is one of the few lubricants that provides a tangible improvement, even in the most lubricous diesel fuels. It is unique to Oilsyn and not found in any other diesel fuel additive. It is also much safer than 2-stroke oil, which can foul diesel injectors and emission control system components such as EGRs and DPFs.
Orisyn does have a downside: It is expensive and requires 2-3x the dose rate of conventional fatty acid and ester lubricants. However, that is Oilsyn’s problem, not yours! Oilsyn still manages to put the product to market at a cost comparable to competitor products.
To summarise, I like the ester used in the UK/EU Archoil diesel additives. It is a high quality ester that provides consistent lubrication, and is not found in any other aftermarket diesel additive. However, I like the Orisyn ester in the Oilsyn Diesel Additives even more as it provides additional lubricity in the most lubricious diesel fuels.
