Engine oil change (Audi 80 B3)

Depending on the operating conditions, motor oils are subject to frequent, changing loads. Therefore, it is very important to accurately determine the effect of different operating conditions on the lubricant. Oil reaches high temperatures in engines operating for a long time at high speeds or at full load. Under the influence of high temperatures and atmospheric oxygen, the oil begins to oxidize. Oxidation products thicken the oil and settle as a varnish-like coating on the upper parts of the pistons, in the grooves of the piston rings, on the valve stems, leading to coking of the valves.

The article was copied from the website audimanual.ru