Shining up your ride is rewarding. But if you’re just buffing the outside sheet metal, wiping down the seats, and vacuuming the carpets, you’re not fully completing your cleaning assignment.


What about the insides of your engine, transmission, and vent system? It's hard to get a broom inside those components; so automotive engineers have fitted them with five essential filters.
Let’s quickly review where you find these vehicle filters, and how often you should change them.

Engine Oil Filter
The least expensive filter and the one that has the most bearing on overall vehicle longevity. Like any filter, an oil filter can only suspend so much stuff. When clogged, not only is its cleaning ability compromised, but also its ability to keep the oil flowing through the engine at the optimum rate.


Obviously replace the filter at each oil change. Check your owner’s manual or on-board oil monitoring system for oil change intervals, but 10,000 kilometres and/or six months would be a prudent upper limit.

Engine Air Filter
An engine needs air (or more precisely oxygen) to combust petroleum.


Like the clogged oil filter, a clogged air filter hinders both cleanliness and flow. And if airflow is compromised, some fuel can go unburned — a dirty, power-robbing, and wasteful outcome.
Generally, air filters can go about 12 to 18 months, or 20-30,000 kms. But have it checked at each oil change.


Or do it yourself, by shining a headlight, flashlight, or trouble light through one side of the filter. If light has trouble getting through, your filter is toast.

Fuel Filter
Fitted between the gas tank and engine, the fuel filter keeps rust, water, dirt, etc., from entering your combustion chamber.

Once again, when these things get clogged, both cleaning ability and flow are compromised. If they get really clogged you can look forward to stalling and hard starting.

Fuel filters are harder to locate; have a mechanic or gearhead friend break the trail for you.
Your owner’s manual will stipulate when you should change them, but history has shown us that they usually last about two years or 45,000 kilometres.

Transmission Filter
If there is a filter change to leave to the professionals, it’s the automatic transmission filter, as it is accessible only when the pan is removed.

Some newer transmissions, especially CVTs, don’t have replaceable filters. But all need to have their fluids changed periodically, which is when you should also change the filter (if there is one). Two years or 50,000 kilometres is a ballpark interval for a transmission service — check your manual.

Cabin Dust and Pollen Filter
A lot of people don’t even know they have a cabin dust and pollen filter, but most new cars have them. Part of the heating and cooling system, they are usually fitted around the glove box, and can easily be checked and replaced by non-professionals.

They are designed to go about one year, but no harm in checking them every oil change.

– Michael Goetz has been writing about cars and editing automotive publications for more than 20 years. He lives in Toronto with his family and a neglected 1967 Jaguar E-type.