When checking the oil level, the dipstick (1) is removed from the guide tube. The oil level should be between the marks or in the area of the ribbed surface (arrow) on the tip of the dipstick. The amount of oil to be added between the marks is 1 l. The measurement can only be accurate if the car is on a horizontal surface.
Constant control
If you have just purchased your Audi A4 (new or used), then, for safety's sake, you should take hold of the dipstick every time you fill up the fuel tank to measure the oil level. Once you know that your engine is consuming very little oil, you can check it between the second and fourth fill-ups.
According to Audi instructions, the oil level should be checked at an engine temperature of 60°C, which corresponds to approximately 10 minutes after starting a cold engine.
Place the car on a horizontal surface.
After turning off the preheated engine, wait at least five minutes for all the oil to drain into the crankcase.
Be careful with a hot engine, you can burn your hand on the surrounding parts.
Remove the dipstick, wipe it with a clean, lint-free cloth or paper towel, reinsert it until it stops, wait a moment, and remove it again.
You can see the oil level on the rod.
If the lubricant level only reaches the lower mark, then engine oil needs to be added.
Tip: If you want to keep an accurate log of your Audi A4's oil consumption, you should always take measurements in the same place and at the same oil temperature.
The black color of the oil itself is not a signal to change the engine oil. The oil darkens again even soon after the change. The falling dirt and abrasion products are kept in suspension so that they do not get inside the engine.
Topping up oil
The difference between the lower and upper marks on the dipstick is 1 liter. The oil level should not fall below the lower mark. A lack of a quarter liter of oil is not yet dangerous, but if more oil is missing and the Audi A4 is driven in a sharp manner, then the oil pressure can drop to a dangerous level on turns.
Excess oil in the engine is also harmful. At high speeds, it can get through the ventilation hole in the crankcase into the combustion chambers. For the catalytic converter, excess oil is as dangerous as unburned gasoline. Consequence: it can melt. But with normal oil consumption, this is not dangerous.
Bottom line: It is recommended to add oil when the level is in the lower quarter between the two marks on the dipstick. Do not fill above the upper mark.
Tip: Oil in small quantities is more expensive than in 3-, 4- or 5-liter canisters. This type of packaging is often inconvenient for adding oil on the road. In addition, it takes up a lot of space in the trunk. A 1-liter can of motor oil with a screw cap is convenient, from which you can add oil in small portions as needed.
Can oils be mixed?
All types of oils from all manufacturers, including single-purpose and multi-purpose oils, can be mixed without fear. This miscibility without harmful consequences is a basic requirement of international oil standards. Although mixing with another engine oil may slightly affect the specific properties of a particular oil, since each brand of oil has its own combination of additives. But the lubricating effect is never compromised. Anyone who adheres to the oil standards recommended by Audi is not at risk of engine damage due to unsuitable oil.
(Text provided by the online resource: audimanual.ru)