Can you change your oil without changing the filter?

Can you change your oil without changing the filter?

With so many people saying “change the filter” and with many good reasons, I’ll give you a few reasons and justifications to say it’s OK.

Many owners manuals say to change the filter every other oil change. I used to collect owners manual and give my students exercises in looking up specs and information. I was surprised at how many manufacturers say this.

On the other hand any technician at a dealership that changed the oil without changing the filter would likely get fired. Or a quick lube shop. Filters are just too inexpensive not to change them. The other difficulty is tracking when the filter was changed. If you change it every time then you can’t lose track.

The argument about diluting your clean oil… well there is much more oil that doesn’t drain from the engine than the 1–2 pints that might be in your filter. The residual oil is going to mix with the fresh oil just the same.

The filter system is not a full flow system (most all cars) and only about 20% of your oil goes through the filter per pan full pumped. Eventually it all does. There is a bypass system should the filter become clogged so that the engine will still get oil. However if you had enough garbage in your oil system to clog the filter the engine would have already been I’m seriously bad condition.

With the above in mind, you should understand the importance of staying with the same brand and weight of oil.

At one time cars didn’t have oil filters and accordingly the oil was changed more frequently. If you’re a person who changes their own oil on schedule or sooner and uses the same brand and weight every time changing the filter every other time won’t hurt anything. (Can’t say it would help anything either)

Would I recommend this practice to a student or technician? Nope.