What is the danger of delaying engine oil change?

Thursday August 8 2019


By Paul Kaganzi

Hello Paul, I failed to change the engine oil of my Toyota Nadia for 3,000kms because I misplaced the service tag. Is there a danger for delaying engine oil change? Benjamin

Hello Benjamin, engine oil is the life blood of your car and must be renewed periodically because it has a life span. Engine oil has the responsibility of cleaning your engine, protecting and enhancing its performance. Delay to renew it reduces the protective and performance enhancing roles of the lubrication system. To understand the importance of engine oil and why it should be serviced regularly, you can compare it with the role of human blood.

Engine oil works in very hot and harsh conditions of the engine which is relatively open to exhaust soot, dust, pollen and combustion gases or acids. Good engine oil is blended with detergent and dispersant additives which clean and carry away soot or dirt. Lubricant and anti-sheer molecules protect fast moving metallic components.

This is why engine oil needs to be filtered to trap the soot and dirt before its return journey around the engine, which helps to avoid harmful sludge build-up. Over the service drain interval, engine oil turns darker and it’s ability to clean, protect and enhance performance reduces.
This is why it must be drained and renewed at service.

Engine drain intervals are usually 5,000kms for normal engines and 3,000kms for older or leaky engines (with bad seals or aged piston rings). Newer vehicle engines can have extended service intervals if they use engine oils blended with semi synthetic or fully synthetic molecules and designed to work well over longer drain intervals (7,000kms or 10,000kms). The decision to use these longer life engine oils should take into consideration the manufacturer’s recommended oil grade or viscosity range, age and condition of the engine.