Engine Oils

What does Engine Oil actually do?


How do I read the '5W40' Type Number?


A quick guide to the different Grades of oil.
Fully Synthetic Characteristics
Fuel economy savings
Enhances engine performance and power
Ensures engine is protected from wear and deposit build-up
Ensures good cold starting and quick circulation in freezing temperatures
Gets to moving parts of the engine quickly
Semi-synthetic Characteristics
Better protection
Good protection within the first 10 minutes after starting out
Roughly three times better at reducing engine wear
Mineral Characteristics
Basic protection for a variety of engines
Oil needs to be changed more often


Viscosity and Viscosity Index(VI).

The proper viscosity is the single most important criteria of a lubricating oil. The basic performance of machinery is based on the viscosity of the lubricant. Viscosity is, if you like, the resistance to the flowability of the oil. The thicker an oil, the higher its viscosity. The chart on the right shows a rough guide to ambient temperatures vs oil viscosity performance in both multigrade (top half) and single grade (lower half) oils.
Multigrade oils work by having a polymer added to a light base oil that prevents the oil from thinning too much as it warms up. At low temperatures, the polymers are coiled up and allow the oil to flow as it's low number (W number) indicates. As the oil heats up, the polymers unwind into long chains which prevent the oil from thinning as much as it normally would. The result is that at 100°C, the oil has thinned only as much as its higher rating. Think of it like this: a 10W30 oil is a 10-weight oil that will not thin more than a 30-weight oil when it gets hot.
The viscosity index of a lubricant is an empirical formula that allows the change in viscosity in the presence of heat to be calculated. This tells the user how much the oil will thin when it is subjected to heat. The higher the viscosity index, the less an oil will thin at a specified temperature. Multi-viscosity motor oils will have a viscosity index well over 100, while single viscosity motor oils and most industrial oils will have a VI of about 100 or less.

Here's a three-line table to give you an idea where typical engine oils are used:

Oil type Typically used in....
5W-30 Cooler climates, like Sweden or Canada
10W-40 Temperate climates, like England
15W-50 Hot climates, like Italy, Spain, Egypt


Why And When To Change Your Oil?

Why change your engine oil?


When to change Oil?

Engine Layouts


The Difference between 4 Stroke and 2 Stroke Engines


How 2 stroke Engines Work




How 4 stroke Engines Work

4 stroke engines are typically much larger capacity than 2 stroke ones, and have a lot more complexity to them. Rather than relying on the simple mechanical concept of reed valves, 4 stroke engines typically have valves at the top of the combustion chamber. The simplest type has one intake and one exhaust valve. More complex engines have two of one and one of the other, or two of each. So when you see "16v" on the badge on the back of a car, it means it's a 4-cylinder engine with 4 valves per cylinder - two intake and two exhaust - thus 16 valves, or "16v". The valves are opened and closed by a rotating camshaft at the top of the engine. The camshaft is driven by either gears directly from the crank, or more commonly by a timing belt. The following animation shows a 4 stroke combustion cycle. As the piston (red) retreats on the first stroke, the intake valve (left green valve) is opened and the fuel-air mixture is sucked into the combustion chamber. The valve closes as the piston bottoms out. As the piston begins to advance, it compresses the fuel-air mix. As it reaches the top of its stroke, the spark plug ignites the fuel-air mix and it burns. The expanding gasses force the piston back down on its second stroke. At the bottom of this stroke, the exhaust valve (right green valve) opens, and as the piston advances for a second time, it forces the spent gasses out of the exhaust port. As the piston begins to retreat again, the cycle starts over, sucking a fresh charge of fuel-air mix into the combustion chamber.


Fuel Efficiency

Fuel economy Concept

More kilometers, more economy.
More environmentally friendly, lower CO2 emissions.
More protection, less wear.
Fuel Economy range of lubricants should meet the requirements of business and private users wishing to improve the performance and lifespan of their vehicles while noticeably reducing fuel consumption.

Calculate the potential fuel savings for your passenger car.

A Fuel Economy lubricants enable a reduction in polluting emissions per km/mile, they optimize the efficiency of vehicle post-treatment systems and prolong engine life due to engine cleanliness and anti-wear protection.

An approved lubricant

The ACEA (European Automobile Manufacturers' Association) rdefines a Fuel Economy lubricant as a lubricant in compliance with ACEA C1, C2, A5/B5, A1/B1 standards. For this, it must successfully undergo an engine test (Test M111FE) in which the fuel economy is measured and established by comparison with the use of the reference mineral oil. The ACEA C1 standard sets this value at 3%, the ACEA C2, A5/B5, A1/B1 standards set this value at 2.5%.

What if we all used Fuel Economy Lubricants?

For an average distance covered of 14,000 km, petrol or diesel, the estimation is 160,000 tons of CO2 not emitted into the atmosphere by comparison with the use of a mineral oil (Results obtained compared to a mineral oil on petrol & diesel engines of 2.9 million PSA Peugeot Citroën vehicles for an average distance of 14,000 km). These 160,000 tons represent the equivalent CO2 absorbed by 2,000 acres of French forests or 1,450 acres of Brazilian forest (FAO source: 75 tons of carbon in the biomass per acre of French forest, 103 tonnes for the Brazilian forest).