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Filters – the good, the bad and the ugly

Regular maintenance and repairs will keep your vehicle safe and reliable. The servicing and replacement of the filters is a must. But how often should this happen?
Dewald Ranft, Chairman of the Motor Industry Workshop Association (MIWA), an affiliate association of the Retail Motor Industry Organisation (RMI), says a filter’s quality is measured by its life and efficiency. “Not all filters are the same quality. The difference between a superior and inferior filter will determine how long the filter will last (life) and its ability to filter efficiently. Using a filter that does not meet this quality measurement will have a significant detrimental effect on your engine wear, fuel consumption and vehicle performance,” he says.
Ian Law, Group Sales and Marketing Director at GUD, explains that there are four kinds of filters in a vehicle namely air, oil, fuel and cabin air. “A quality air filter has to perform two vital functions: To filter out as much dust, dirt and other impurities as possible, while still providing an adequate flow of air that the engine requires for good performance. They also have to last for the recommended service interval of the vehicle,” he says.
He explains that poor quality air filters can restrict air flow, causing increased fuel consumption. “They can also have less filtration media which means they may not be able to last the recommended service interval. Quality filters, such as GUD filters, use the optimal amount of media of the highest quality for optimal dirt-holding capacity, while still providing adequate airflow to the engine.”
The oil filter is the heart of the vehicles’ lubrication system. The oil filter is responsible for the filtration of contaminants from the oil, allowing clean oil to flow through the engine. Ranft explains that impurities in the oil can cause vital engine components to wear out more quickly, shortening engine life. “Most oil filters are equipped with safety features such as bypass valves and anti-drain back valves, to ensure that the flow of oil to the vital engine parts is not blocked. Cheaper oil filters may have incorrect valve opening pressure allowing oil by-pass and damage-causing dirt particles to enter the engine.”
In today’s modern high-tech engines, Ranft says fuel filters play a vital role in keeping dirt and water out of the fuel injection system with little room for error. Law explains that modern engines, with their smaller injector sizes and higher injection pressures, are especially susceptible to dirty fuel and water contamination. “It is therefore imperative that only reputable aftermarket fuel filters are used,” he says.
With higher levels of dust and pollution found in the atmosphere, cabin air filters are increasingly being used in today’s air-conditioned vehicles. Their main function is to filter out dust, soot, smoke and other impurities from the ventilation system to the aircon. An efficient cabin air filter ensures the driver and passengers breathe easier and keeps them clear from allergies that come from dust and dirt. A poor-quality filter will allow the dirt to enter into the car cabin making driving a very unpleasant experience.
“While its difficult to say exactly how long the filters will last what is predictable is that the better-quality filters last longer and are more effective. Speak to your mechanic during your next service about the brand of filters being used. Remember that you get what you pay for. Going for a cheaper option may not work out cheaper in the long run as the filters need to be replaced more regularly. Make sure you are using a MIWA-accredited workshop for quality products and service,” he concludes.