Knowing when your vehicle needs fresh oil is essential for keeping the engine running smoothly and avoiding expensive repairs.
Warning signs such as unusual engine noises, dashboard warning lights, reduced performance and the colour of the oil itself can quickly lead to serious engine issues if it isn’t addressed.
This car maintenance guide highlights five signs to help drivers know when to carry out an oil change.
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How often should oil be changed?
How often you change your engine oil depends on the vehicle, driving conditions, and the type of oil that is being used – however, most vehicles will need a change every 5,000 to 10,000 miles unless specified otherwise in the service interval.
Older, higher-mileage vehicles may need more frequent oil changes and car servicing.
Drivers who regularly travel short distances, sit in heavy traffic on a regular basis, tow heavy loads or drive in extreme temperatures may also need more regular oil changes.
It is important to keep a regularly changing the oil, along with the oil filter at the same time, to maintain performance, improve fuel efficiency and, primarily, reduce wear and tear on important engine components.
Signs your car needs an oil change
Regular oil changes are one of the most important parts of vehicle maintenance because engine oil keeps hard working engine components lubricated and at the correct temperature.
Over time oil becomes degraded and dirty, meaning it is less effective at lubricating and cooling. This can have serious consequences for the engine, including metal-on-metal friction that leads to irreversible damage and catastrophic engine failure.
Here are the five main signs that your car needs an engine oil change:
Dashboard warning light
The oil engine warning light will most likely appear on the dashboard if there is a problem.
It normally signifies that there is an issue with either the pressure or levels – and it should be addressed as soon as possible.
If it has illuminated on the dashboard it could be due to old or dirty oil struggling to circulate through the system.
In most modern vehicles, there are sensors throughout the vehicle that can monitor this constantly.
If you continue to drive, the engine could overheat or fail and cause further damage – and a larger repair bill.
Read more: Car dashboard warning lights
Dark or dirty engine oil
Fresh engine oil is usually amber or a light brown colour – and has a smooth consistency.
If it is dark and has collected dirt, then it needs to be replaced as soon as possible.
The dirt is usually carbon deposits or small metal particles – which cause the oil to become thicker.
Dark and sludgy oil struggles to go through the system and will lead to underperformance and overheating.
Clean oil is critically important for several key components of the engine.
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Engine noises
One of the clearest signs of an issue with a vehicle is hearing unusual or loud noises coming from the engine.
Engine oil creates a protective layer between the metal moving parts in the engine, and old oil is less able to correctly lubricate them. This can lead to loud grinding and squealing noises.
Ticking or knocking sounds could mean that those parts are now seriously damaged and need urgent attention.
All these noises will get more noticeable once the engine has been in action with old or incorrect oil for an extended period of time.
Increased friction will not only create loud noises, but will also rapidly increase the temperature within the engine – creating more serious problems that will need to be addressed immediately.
Reduced fuel efficiency
A sudden drop in fuel efficiency can indicate that the engine oil needs replacing.
When oil becomes old or contaminated, the engine has to work harder to generate power, leading to increased fuel consumption.
Drivers may also notice that they are filling up their fuel tank a lot more often than previously.
Exhaust smoke and burning smell
If you can visibly see excessive smoke coming from the exhaust, that is accompanied by a burning smell in the car, then it is a common sign that there is an issue with the engine oil.
Thick grey smoke is a sign of engine oil burning, but drivers may also notice the engine being a lot hotter than normal.
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