Oil sludge & how to prevent it


Oil sludge or engine sludge is a black, grease like deposit that forms on a petrol car engine. Oil sludge is likely caused by extended oil change intervals or through missing car services.

Oil sludge can also form on diesel engines, although not as frequently. The process is slightly different but diesel engines have higher levels of unburnt fuel and combustion soot. These contaminants build up over time causing oil to thicken, forming oil sludge.

How will oil sludge affect my car?

Oil sludging is the process of engine oil thickening. The sludge can hinder moving parts through blocking the lubricating system. Engine oil cools a car and ensures that moving parts move freely without any wear. This sludge stores heat rather than releasing it as oil is in place to do, placing stress on your cooling system and causing your engine to overheat. Oil sludge also places stress on other areas of your car because it isn’t working to reduce wear and tear on components, which can lead to the need to replace them, an expensive exercise. All of the above affect your car’s economy, reducing fuel consumption.

How to avoid oil sludge

Oil sludge isn’t a simple ailment to rid your car of, so prevention is the best medicine, have your car serviced at the regular intervals suggested by the manufacturer.

Ensure good quality oils and filters are used, and that they are the appropriate grade for your car.

If you use your car in a way that the manufacturer deems as severe, such as city driving that puts stress on your engine through a lot of stoping and starting, consider having your oil checked more regularly. The same applies for cars doing less than 10,000 km per year. Talk with your mechanic, they may suggest you revise your servicing to 7,000 km or every 6 months, which ever comes first.

If you perform oil changes yourself make sure the engine is warmed before draining the old oil. This will help ensure you remove all the old oil. To ensure you fully flush the engine you could try an engine flush style detergent.

Check your oil regularly to ensure it is in good condition. This will help you maintain a healthy vehicle.