When determining when to change engine oil in a car, most drivers are guided by the odometer reading. According to the manufacturer's recommendation, the frequency of the procedure should be (depending on the car brand) every 10-15 thousand kilometers.
However, one cannot be categorical on this issue. The frequency of engine oil change does not directly depend on the vehicle mileage, but on the operation of the power unit. What affects the quality of the lubricant?
What affects the frequency of replacement
The engine oil must be changed in order for the engine to be cleaned of the resulting waste. Also, the burned-out grease becomes thicker and ceases to cope with its purpose (to provide the surface of rubbing parts with grease). Therefore, first of all, the frequency of its replacement depends on how quickly the burnout occurs.
This is influenced by many factors. Here are the main ones.
- Temperature condition of the engine. Gasoline, propane and diesel heat up the power unit during combustion. Modern engines can heat up to 115 degrees. If the internal combustion engine often overheats, it "gets old" faster.
- Oil type. There are three main types of lubricants. It is synthetic, semi-synthetic and mineral. They all have their own density and boiling point. Using the wrong brand will shorten the term of use of the lubricant.
- The ingress of coolant and fuel into the oil will change the characteristics of the lubricant. However, in this case, before changing it, you need to find and eliminate the reason why foreign liquid has got into the oil. Often this problem indicates a violation of the tightness of the connection between the cylinder block and the cylinder head (gasket replacement will be required).
The following are factors that depend on the driver and the operating conditions of the machine.
- Motor operating mode. When the car often drives at low speeds or moves slowly in traffic jams, the oil does not cool well, which also reduces the oil change interval due to overheating.
- Driving mode. One of the key factors on which the quality of the engine oil depends. In city mode, the driver speeds up and slows down more often. Therefore, driving at medium revs is almost impossible. Driving on a flat road keeps the oil temperature at the same level. This happens even at high speed (but within the permissible engine speed range).
- Loads on the cylinder-piston group. Driving on long climbs and descents, as well as driving with a heavy trailer, increases the load on the engine. Because of this, the temperature of the oil on the piston oil scraper rings increases, which reduces its service life.
Correct oil change interval
As you can see, maintenance should not be carried out based on the car's mileage. For this, experts have developed a special formula, which determines when, in fact, it is necessary to make a replacement. The result of this formula is engine hours. That is, it calculates the engine running time.
For example, the car manufacturer set a deadline for changing engine oil at 10 thousand kilometers. If the driver often drives on the highway, then he will travel this distance in 100 hours at a speed of 100 km / h. However, the lubricant will still be serviceable. But if you move in the "city" mode with a cruising speed of 25 kilometers / hour, then the car will work about 500 hours. In this case, the oil will be black during the change. As you can see, the same distance has a different effect on the condition of the oil.
Calculations of specialists
As already noted, the frequency of visits to the service station also depends on the brand of oil. Below is a table that allows you to determine these intervals, based on the operating hours. Data provided by American Petroleum Institute.
|Motor oil brand||Approximate number of operating hours|
|Polyalphaolefin based (5W40)||350-400|
|Based on polyesters and diesters (ester) (7.5W40)||400-450|
To calculate the number of operating hours, the vehicle must be equipped with an electronic control unit. Among other things, the device calculates the average speed of the car over the distance traveled. Calculations are carried out according to the following formula. The number of operating hours (indicated in the table) is multiplied by the average speed (ECU indicator). The result will be the necessary regulations: the maximum mileage, after which maintenance of the power unit will be required.
Why do you need regular oil changes
Any lubricant, be it synthetics, semisynthetics, or mineral water, consists of a certain amount of additives. Depending on the manufacturer, they have their own "shelf life", or the resource at which the additives remain in their original state. In some cases, it may be necessary to change the oil after a certain time.
When the car is idle for too long, the additives in the oil begin to degrade. As a result, the motor will not be protected, even at an ideal dipstick level. Therefore, some manufacturers recommend replacing at intervals of several months, or once a year.
Of course, it is up to each driver to decide when to change the engine oil. It should be based on the individual parameters of the transport, the loads on the engine and the technical parameters of the internal combustion engine.
In addition, watch a short video on oil change intervals: