Have you ever been told at an oil change that you needed a new filter? Understand how these work before you agree to buy a new one. You may not need it as badly as you think.
When you go in for an oil change,
one of the things the mechanic is going to look at is your oil filter. Filters are an important part of this entire system. Understanding how they interact with your car will help you take the best possible care of your vehicle, and also help you answer the mechanic's questions when they ask is you want to replace your filter when you are in for service.
The lubricant in your vehicle is vital to your vehicle's overall performance. It cools the engine as it transfers heat from one area to another, it seals the gap between the piston rings and cylinder walls, and it absorbs containments and particles that can damage other areas of your engine. These contaminants can be things like dust that have been sucked into your engine or organic particles like bacteria or fungus.
This is a very normal part of the function of your engine, but it does create one problem. If left this way, the lubricant would quickly become saturated with these particles. This would allow them to start wearing down on the engine's vital components. Soon the life of the engine would deteriorate. The only solution was a more frequent oil change.
Luckily, in the early 1920s, filters were introduced to these systems. In the beginning, they were sold as aftermarket or optional equipment. People who wanted to extend the life of their engines or cut back on the number of times they need to service their engines would install them. In the 1950s, they started showing up as standard in vehicles. This allowed drivers to go much longer between one oil change and the next without the lubricant becoming contaminated.
Filters continued to improve, and by the 1960s, 4,000 miles on a service was possible. Today, some manufacturers are stating that 10,000 miles is the number to shoot for between trips to the mechanic for service. Yet, in spite of these improvements, it is the design of the engine, not the function of the filter, that has improved.
The filter is housed in a metal can that is placed against the engine's mating service and has a sealing gasket. The filter material is inside the can. It is typically made from a synthetic fiber. The dirty lubricant is pumped into the can, through the fiber, and out toward the bearings. The filter's fibers are so close together that they trap contaminants, leaving mostly clean oil when it heads back to the engine. Most filters have two filtering media, one that traps larger particles and one that trips the tiniest.
Eventually, the filter will become so full of particles that oil cannot flow through it. The car has a bypass valve for this situation, but once the lubricant goes through the bypass valve, it is not getting cleaned.
So, when your mechanic tells you that your filter needs to be changed during your next oil change, ask to look at it. If it appears to be full of particles, then it just might need cleaning. If it still looks fairly clean, then you are free to wait until next time to change it.
