Even in sub-zero temperatures, motorists should regularly check their vehicle’s engine oil level.
“The outside temperature is irrelevant when topping up. However, it should be avoided as much as possible to dump ice-cold oil – for example from the unheated garage – into a hot unit.”
The oil level is checked when the engine is cold. When doing so, park the vehicle horizontally. During a fuel break, wait about five minutes until the lubricant has run down again. The level should be between the minimum and maximum marks.
Refer to the vehicle owner’s manual for the amount between the notches on the dipstick. “When topping up, be careful not to add too much oil. This is harmful to the engine’s seals. In addition, foaming can cause a lubricating film to break off,” emphasizes the expert.
But which oil is suitable for which engine? A look at the oil slip from the last change often helps. Only the approvals of the automobile manufacturers are decisive. They can be found in the operating instructions and on the labels of the oil cans – for example VW 507 00 or BMW Longlife-04. If possible, stick to the same brand because of the different additives.
Viscosity is an important factor, but there are other components such as base oils and additives. For example, a 5W-30 oil may have the correct viscosity grade, but it does not necessarily have to meet all the manufacturer’s specifications.
Viscosity classes are often mistakenly equated with manufacturer approvals. But viscosity merely defines the flow behavior of a fluid. Tough as honey or thin as water are examples of high or low viscosity.
“Multigrade oils must be able to do both, i.e. ensure the required lubrication over a wide temperature range.”