According to Juri, oils of grades 0W-16 and especially 0W-8 are not a \u201cuniversal way to save fuel,\u201d but part of a complex engineering solution in which bearing design, piston group, cooling system, and engine operating modes are calculated for minimal friction losses. The use of such oils outside the range specified by the vehicle manufacturer can reduce the economic effect to zero or lead to accelerated wear.<\/p>\n\n\n\n
Engines lose energy due to friction losses in four main areas<\/strong><\/p>\n\n\n\nPiston and cylinder<\/strong> \u2013 pistons and rings account for approximately half of total engine friction losses. Energy losses occur in the contact zone between piston rings and the cylinder liner throughout the entire operating cycle.<\/p>\n\n\n\nGas distribution mechanism (valvetrain)<\/strong> \u2013 friction in it can make a significant contribution to total engine friction losses, especially at low engine speeds (RPM). This is mainly friction occurring in camshaft bearings and friction between the valve and the tappet.<\/p>\n\n\n\nOil pump<\/strong> \u2013 during engine warm-up, a large energy loss often occurs due to pumping high-viscosity oil through the engine.<\/p>\n\n\n\nCrankshaft<\/strong> \u2013 here friction occurs in the main and connecting rod bearings.<\/p>\n\n\n\nOils with lower viscosity improve fuel economy and, as a consequence, reduce greenhouse gas emissions. However, higher-viscosity oils can provide a thicker oil film; however, the level of protection is determined by the combination of viscosity characteristics and the additive package. Therefore, the task is to find an engine oil that provides a balance between fuel economy and engine protection.<\/p>\n\n\n\n
Engineering balance of ULV oils: view of Juri Sudheimer<\/strong><\/p>\n\n\n\nJuri Sudheimer emphasizes that the key difficulty in developing ultra-low-viscosity oils is not reducing viscosity itself, but maintaining a stable oil film under boundary friction conditions. It is precisely these conditions\u2014engine start-up, low RPM, high loads\u2014that determine real engine service life.<\/p>\n\n\n\n
According to Juri\u2019s observations, the transition to 0W-16 and 0W-8 oils became possible only due to the development of additive technologies: highly effective friction modifiers, film-forming additives, and new detergent systems. Without these solutions, reducing viscosity would inevitably lead to a decrease in protection; therefore, ULV oils are not a compromise at the expense of durability, but the result of technological evolution of engine oils.<\/p>\n\n\n\n
There are two main ways to reduce fuel consumption using engine oil<\/strong><\/p>\n\n\n\n1. Reduction of hydrodynamic friction by lowering oil viscosity<\/strong><\/p>\n\n\n\nHydrodynamic lubrication is a regime in which the rubbing surfaces are completely separated by a load-bearing oil film, and direct metal-to-metal contact is absent. In this case, resistance to motion is mainly determined by shear in the lubricant layer volume, i.e. losses due to internal fluid friction. Therefore, under otherwise equal conditions, lowering viscosity can reduce hydrodynamic friction and related energy losses.<\/p>\n\n\n\n
However, in real friction units the lubrication regime changes over time. In most highly loaded contacts (in the engine, transmission, bearing units), under certain conditions\u2014start\/stop, low sliding speeds, high specific loads, local overheating, film thinning\u2014the system transitions into mixed and\/or boundary lubrication.<\/p>\n\n\n\n
In boundary lubrication, a full load-bearing fluid film is not sufficient to completely separate surfaces. The risk of increased wear and seizure is limited by the formation on the metal of protective tribofilms of various origins\u2014adsorption layers, tribochemical reaction products, and\/or reaction films of additives. Wear in such regimes may be accompanied by formation of both base metal particles and products of interaction between the surface and the lubricant (tribofilm components).<\/p>\n\n\n\n
2. Reduction of boundary friction and wear through additive technologies<\/strong><\/p>\n\n\n\nIn mixed and boundary lubrication regimes, the friction coefficient and wear are largely determined by the composition, structure, and strength of tribofilms on working surfaces. Therefore, the key engineering tool for reducing friction in these regimes is the use of friction modifiers (FM) and antiwear\/extreme pressure (AW\/EP) systems.<\/p>\n\n\n\n
Consequently, in the boundary region, reduction of losses is achieved not by \u201cworsening anti-friction properties,\u201d but on the contrary\u2014by forming more effective anti-friction and protective surface layers that are resistant to load and temperature.<\/p>\n\n\n\n
Viscosity balance: why savings must not destroy durability<\/strong><\/p>\n\n\n\nThe oil must be sufficiently viscous to ensure separation of important engine parts, but sufficiently fluid for the engine to operate economically. Reducing fuel consumption by reducing engine protection is a compromise that should not be made. That is why completely new technologies were developed for creating ULV oils.<\/p>\n\n\n\n
Everything began when, in April 2013, the SAE J300 international engine oil viscosity classification was amended for the first time in 12 years. This was related to the fact that at that time a large number of vehicles in Japan were already de facto using low-viscosity oils below 0W-20. SAE J300 added oil grades SAE 8, SAE 12, and SAE 16.<\/p>\n\n\n\n
0W-16 oils<\/strong> 0W-16 oils are typically produced on the basis of synthetic base oils to ensure required characteristics, having very low viscosity at operating temperature (from 6.2 to 8.2 cSt at 100\u00b0C) and low high-temperature viscosity (min 2.3 at 150\u00b0C), which reduces friction losses and increases fuel economy by 1\u20132% compared to 0W-20 oils.<\/p>\n\n\n\nThese oils are produced using conventional technology with the use of viscosity modifiers, and the necessary anti-friction and anti-wear properties are provided by high-quality synthetic base oils and the latest friction modifiers based on boron, molybdenum, and other metals.<\/p>\n\n\n\n
They are designed for engines requiring ultra-low-viscosity oils for maximum fuel economy and reduction of CO\u2082 emissions, for example, hybrid vehicles\u2014more precisely parallel hybrids and their variants. Series hybrids require conventional oils such as 0W-20 and 0W-30, since in them the internal combustion engine operates constantly in a normal thermal regime.<\/p>\n\n\n\n
0W-8 oils<\/strong><\/p>\n\n\n\n0W-8 oils are created using a completely different technology. In 2019, the Japanese standard JASO GLV-1 was introduced, oriented toward ultra-low-viscosity engine oils. This is a Japanese specification for ultra-low-viscosity engine oils (0W-8 and 0W-12) for gasoline engines, developed by the Japanese Automotive Standards Organization (JASO) for maximum fuel efficiency and reduction of CO\u2082 emissions.<\/p>\n\n\n\n
At the same time, these oils must protect against wear and LSPI (low-speed pre-ignition). They must pass Nissan fuel economy tests (JASO M365) on the Nissan MR20DD 2.0 L engine and Toyota tests (JASO M366) on the Toyota 2ZR-FXE engine with a displacement of 1,797 cm\u00b3. According to standardised fuel economy test results, the difference compared to 0W-16 can be about 0.7%.<\/p>\n\n\n\n
Their viscosity is in the range of 4.0 to 6.1 cSt at 100\u00b0C, with high-temperature viscosity minimum 1.7 at 150\u00b0C.<\/p>\n\n\n\n
ULV oils: not a universal recipe, but a precise engineering tool<\/strong><\/p>\n\n\n\nUltra-low-viscosity engine oils are not a step toward \u201csaving at any cost,\u201d but the result of the evolution of engines and lubrication technologies developing hand in hand. They provide real effect only in engines originally designed for such operating modes, materials, and lubrication systems.<\/p>\n\n\n\n
That is why oils of classes 0W-16 and 0W-8 cannot be considered a universal replacement for more viscous products\u2014they are a precise tool requiring strict compliance with vehicle manufacturer recommendations. Otherwise, potential fuel savings easily turn into loss of engine life, and technological progress into an expensive mistake.<\/p>\n\n\n\n
In a number of ULV oil formulations, the content of viscosity modifiers is minimized due to the use of specialized base oils and film-forming additives: film-formers that increase oil film thickness without increasing oil viscosity. As friction modifiers, as in 0W-16, the latest friction modifiers based on boron, molybdenum, and other metals are also used. Organic friction modifiers (OFM) may also be used in such oils.<\/p>\n","protected":false},"excerpt":{"rendered":"
Despite humanity gradually transitioning to hybrid and fully electric vehicles, according to forecasts of a number of industry analysts, in the coming decades, a significant share of the global vehicle fleet will still be equipped with internal combustion engines, including…<\/span><\/p>\nRead more ›<\/a><\/div>\n<\/p>\n","protected":false},"author":2,"featured_media":7731,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"footnotes":""},"categories":[2],"tags":[],"class_list":["post-7729","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-advice"],"_links":{"self":[{"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/posts\/7729","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/comments?post=7729"}],"version-history":[{"count":1,"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/posts\/7729\/revisions"}],"predecessor-version":[{"id":7732,"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/posts\/7729\/revisions\/7732"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/media\/7731"}],"wp:attachment":[{"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/media?parent=7729"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/categories?post=7729"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mocktheorytest.com\/resources\/wp-json\/wp\/v2\/tags?post=7729"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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