The Journey of Lubricants in Engines

Join us in the journey of lubricants in engines as we discover why it is necessary to prevent friction between metal components in every mechanical application. Engine lubrication ensures that sufficient oil is supplied to the lubrication points of the combustion engine in all operating states. It primarily has the function of ensuring adequate lubrication of the engine in your car.


Without enough oil, the engine would break down very quickly. We are sure we’re not telling you anything new. In this article, we would like to explain to you how it all works when the oil is inside the engine. Depending on the type of engine, different methods can be used, and they are:

  • Wet Sump Lubrication
  • Dry Sump Lubrication
  • Mixed Lubrication
  • Splash Lubrication

Wet Sump Lubrication

Pressure circulation lubrication, also known as wet sump lubrication, is used in most cars today, regardless of whether they are diesel or petrol vehicles. Wet sump lubrication is the norm in most modern cars.

The technology with which this works can be explained very simply. First, there must be a circuit in which the engine oil travels all around the engine for the wet sump lubrication system to work. The oil normally sits in the oil pan when the engine is off by using the earth’s gravity.

When you start your car, the oil pump sucks the oil up and pumps it first through the oil filter and then through the lines that transport the oil to where it is needed for lubrication. The correct oil pressure ensures that the oil can also reach areas that are further away.

Since the oil cannot reach some points in this way, there are still nozzles or holes within the circuit, for example on the crankshaft. In this way, areas can also be supplied with oil that could not be reached by pumping alone.

The oil then flows back into the oil pan. From there it is sucked in again by the oil pump and pumped back into the engine through the oil filter. This cycle repeats itself constantly while you are driving.

Incidentally, the oil also absorbs heat in the engine and then cools down in the oil pan before it is pumped back into the circuit. As a result, in addition to its main task of lubricating, it contributes to engine cooling.

AMSOIL SAE 5W-30 Motor Oil

For wet sump lubrication, we recommend AMSOIL’s Signature Series SAE 5W-30 Synthetic Motor Oil. It features a precision formula crafted using cutting-edge technology and a longstanding devotion to make the world’s best motor oil.

Dry Sump Lubrication

Example of Dry Sump

Like wet sump lubrication, dry sump lubrication is a form of circulation lubrication. In this option, as a difference, the oil is transported in a separate oil tank and an additional pump is used to return it from the engine.

This allows a larger quantity of oil to be pumped through the engine when driving compared to wet sump lubrication, which improves the cooling effect of the oil. This form of engine lubrication is used, for example, in some exclusive sports cars and motorcycles.

AMSOIL V-Twin Oil Change Kit

We recommend AMSOIL Synthetic V-Twin Motorcycle Oil for dry sump applications. It is the result of extensive research and is specifically designed to excel in all areas unique to motorcycles.

Mixed Lubrication

Snowmobiler in deep powder snow in back country using AMSOIL Synthetic Lubricants

Mixed lubrication is still used in two-stroke engines, and it can also be called petroil lubrication. In this system, the necessary lubricating oil is added to the fuel, and mixed. It gets to the lubrication points by traveling with the fuel and then takes part in the combustion process.

There is also an automatic version of this type of lubrication called consumption lubrication. In this version, a pump transports the separately carried lubricant to the relevant points. Then the oil gets burned. This system is used in large two-stroke engines, such as 2-stroke marine diesel engines.

2 Stroke Injector Oil

Our recommendation for this type of engine is AMSOIL’S Synthetic 2-Stroke Injector Oil. It offers the convenience of one formula for the toughest conditions of all two-stroke recreational equipment, including snowmobiles and outboard motors.

Splash Lubrication

zero turn landscaper

Splash lubrication uses centrifugal force, and it is a very simple method of engine lubrication. It is the system that steam engines of the past used because it was cheap and durable at the time. These types of lubrication systems might need separate fuel pumps to lubricate other components located outside the engine.

In splash lubrication, the oil is thrown onto the parts to be lubricated in the truest sense of the word with small rotating shovels. This type of engine lubrication is often used in lawn mowers, for example.

At the moment, we do not carry any specific products for splash lubrication systems, however, please do not hesitate to check out AMSOIL’s search engine to find the type of oil you might need.