Therefore it’s no surprise that the correct oil mixtures produced synthetically by the Formula 1 suppliers has to be determined and constantly adapted as part of a complicated procedure. It’s also no surprise that manufacturers such as Castrol, Mobil and Shell keep their chemical formulas under lock and key – just like the tyre manufacturers. One thing is certain, the oil used in Formula 1 is extremely free-flowing and almost has the consistency of water; this at first seems somewhat surprising, because high-viscosity oil would cool better. However, low-viscosity oil allows the engine to rotate faster.

“The lubricant determines the so-called friction coefficient between the engine parts that slide over each other,” says Dr David Hall, Head of Lubrication Development at Castrol. “The lower it is, the easier and faster all the parts can move. Therefore, low friction results in higher speeds, along with lower friction loads on the components and a reduction in fuel consumption.”

The oil supplier provides roughly 30,000 litres of engine oil, as well as 3,000 litres of gearbox oil, for Formula 1 cars (which includes races, testing and benchwork). For each race event Castrol supplies approximately 200 litres of engine oil and 75 litres of gearbox oil.

As so often in motorsport, lubricants have to achieve a compromise between performance and reliability. If the oil is too thin, then it may lead to premature faults, such as damage to the engine or gearbox. Weight also plays a role: thinner oil does not conduct heat so well. For this reason more of it has to be used, which in turn increases the car’s weight.

The engine contains roughly 10 litres of oil, of which seven litres are located in the crankcase and cylinder area. “During testing, the engine oil is renewed on a daily basis”, says Dr Hall, “sometimes some oil is drained off, when various oil levels are being tested as part of different set-ups.”

The optimum composition of the lubricants is determined by the manufacturers with the help of a computer – this applies both to passenger car production and motor-sport. For the latter, however, differentiations are also made from race track to race track. For instance, at narrow tracks, such as at Monaco, the teams opt for a high-viscosity oil. This is because the high load, due to permanent changing between acceleration and braking at high speeds in low gears, causes the temperatures in the engine to rise higher than normal.

Finding the ideal mixture is a long process: the oils mixed in the computer are produced in small quantities for testing purposes. If these prove to be successful, then the lubricant has to be tested by Formula 1’s ruling body, the International Automobile Federation (FIA), to see whether it complies with regulations. Only then are larger quantities produced, which in turn are subject to constant purity monitoring.

The most important task for the developers doesn’t start until the weekend of the race. The specialists at the track take oil samples from the Formula 1 cars each time they come back in after a practice session. By using X-ray equipment they can detect any metal residue which makes its way into the oil due to engine and gearbox wear. This means that under certain conditions engine damage can be avoided. Depending upon the oil’s degree of impurity, the engineers can then decide whether a part may have to be replaced straight away.

Indeed, nowadays it is even possible to control the oil flow by computer during a race. This in turn means that any impending faults can be avoided in advance, thus allowing spectators at Monza to enjoy the full sound of the engine – lap after lap.

In passenger cars, engine oil must not only lubricate moving parts, it must also perform a variety of other tasks. Frictional heat must be dissipated, wear particulates must be removed and contamination flushed out. In addition, corrosion protection must be provided for the engine. To ensure that the engine oil can fulfil all these tasks the basic oil has up to 20 percent additives added to it, from viscosity index enhancers for better temperature properties on to dispersants and anti-wear additives. Fully synthetic basic oils, as used in Formula 1, are also making their way into passenger car production.

“Fully synthetic low-viscosity oils can, in particular, lower fuel consumption for short-distance traffic by up to five percent”, says Dr Christoph Lauterwasser from the Allianz Centre for Technology (AZT) in Munich. “Of course, they are significantly more expensive than conventional oils; the reduction in fuel consumption, however, compensates for this effect. In addition, where cold starting takes place frequently, the engine is better preserved by the improved lubricating property and flow behaviour. An additional positive effect also applies to diesel engines: particulate emissions are significantly lowered.”

However, even the finest of oils have to be changed on a regular basis, even if some manufacturers are increasing the service intervals. Here, it is essential to adhere to the oil specifications prescribed by the manufacturer. Anyone choosing to change the oil by themselves should – for reasons of environmental protection – observe cleanliness and make sure that the used oil is disposed of properly. All dealers that sell oil are obliged to accept any used oil that is returned.