Being thin has its advantages, at least when it comes to engine oils. This especially benefits lubrication in heavy vehicles, resulting in reduced wear and lower fuel consumption. 

THINNER OILS WORK WELL IN HEAVY VEHICLES

There’s nothing to say that you must use thick oils in a heavy vehicle fleet. On the contrary, a 5W or 10W oil provides better lubrication than a 15W oil. The thinner oil reaches difficult-to-access areas more easily and lubricates the engine faster and more effectively than a thicker. The reduced wear can contribute to lower fuel consumption. 

Oils adapted for environmental engines also safeguard the life of emission control systems in construction machines and other heavy vehicles. The correct oil reduces the risk of clogged diesel particulate filters. 

In a truck engine, every degree of viscosity improves the startability by 5 degrees. So on a cold winter day, a 5W oil improves startability by 10 degrees compared to a 15W oil. 

With a thinner engine oil, you avoid having to idle to keep the engine ticking over on cold days. This reduces wear, and is known as ‘a heated garage in a can’. And of course, no idling is good for lowering costs and to the environment.

THE OIL FLOW IN A TRUCK ENGINE MOVES QUICKLY AND A LONG WAY

Oil covers a distance of 9.5 metres as it travels round all the nooks and crannies of an engine. Consequently, it is crucial that there is no soot or oxidation to obstruct the flow of oil. Due to the constant flow, each component in the engine is passed and lubricated by 135 litres of oil per minute. 

IT IS IMPORTANT TO CHANGE GLYCOL REGULARLY

It is important to not only add new glycol, but to change it completely. For the best types of glycol, the rule of thumb is to drain the system completely and change every 3–5 years. For lower quality glycol, ideally change it completely as regularly as once a year. Changing the glycol will ensure that the corrosion system works and safeguards the life of the water pump. 

THE REQUIREMENTS ON ENGINE OIL HAVE BEEN RAISED

The background is that emission requirements for heavy vehicles have increased dramatically in the past 30 years, for nitrogen oxides by as much as 90%. This has been achieved due to major changes in engine construction, which in turn has led to tougher requirements on engine oils. Oil must now cope with an increasingly tough environment and safeguard the life of post-treatment equipment, primarily the diesel particulate filter.

THINNER OILS MAKE A DIFFERENCE IN GEARBOXES AND REAR AXLES

If you are used to getting thick oily lumps in your gearbox, it is easy to avoid this. In the rear axle or gearbox too, thinner oils help to reduce wear, while fuel consumption is also reduced due to lower viscosity in the driveline. 

By Morten Herregarden, FUCHS Lubricants