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Knowledge that protects engines

Practical, independent explanations of oil specifications, viscosity, lubrication, engine protection, and automotive fluids.

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Automotive lubricant testing in a modern laboratory

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Unbranded engine-oil bottles and a clean engine component illustrating Porsche oil approval selection.
Specifications Explained

Porsche A40, C20, C30, C40 and C40 GT Engine-Oil Approvals Explained

Porsche oil codes identify manufacturer approvals, not just oil thickness. This guide explains the practical meaning of A40, C20, C30, C40 and C40 GT, why two 0W-40 oils may still be unsuitable substitutes, and how to verify the correct approved product for a Porsche engine.

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Things to Know About Viscosity Golden motor oil demonstrates different flow behavior at cold and warm temperatures.

What is Oil Viscosity a.k.a. Oil Weight?

Viscosity is a fluid’s resistance to flow. In case of lubricants the viscosity is very important because it affects the oil’s ability to reduce friction and transfer heat. The viscosity is measured in mPa*s (millipascal-seconds)...

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Things to Know About Viscosity Low-viscosity golden oil flows through transparent channels around precision bearings.

The SAE 16 Viscosity Grade

On April 1, 2013 the Society of Automotive Engineers (SAE) introduced a new viscosity grade called SAE 16. This is a new high temperature viscosity grade hence it's not 16W just simply 16 or SAE...

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Oils and Lubrication A mechanic checks a car engine oil level while preparing the vehicle for winter.

10+1 tips to prepare your car for the winter

To help you to prepare your car for the winter oilspecifications.org compiled a checklist about the most important things to do to make sure that your car is appropriately prepared for the winter. This checklist...

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Specifications Explained An engineer inspects a motor oil sample beside a gasoline engine test stand.

API SN Engine Oil Category

In 2010 the American Petroleum Institute introduced a new engine oil category under the name API SN and a new supplemental category called Resource Conserving. The API SN category is an improvement over the API...

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Specifications Explained A mechanic services the wet clutch assembly of a modern motorcycle.

JASO MA and JASO MB classifications

Modern motorcycles usually have the same oil lubricating the engine and the wet clutch. For this purpose most of the time the regular friction modified engine oils are not good enough. To make sure that...

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Oils and Lubrication Lubricants, bearings, gears, piston rings, and laboratory glassware arranged on a workbench.

Lubrication glossary

Additive A compound mixed to the base oil in order to modify its properties or performance. Base Oil Usually refined crude oil fraction or selected synthetic base stock. Additives are mixed to them during lubricant...

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Oils and Lubrication A cutaway engine shows oil paths around pistons, valves, and a turbocharger.

What Are The Reasons of Oil Consumption?

One of the dreaded things car owner face is oil consumption. For some people the only time when they have to do anything motor oil related is the time when they find out that its...

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