Many people seem to be confused. 5k, 8k, 10k… How often should I change my oil??

This is a very good question, and one that we get asked quite often. Oil and engine technology has come a long way in the recent years.

Some people are still living by the 5,000km oil change interval regardless of the oil they are using. So, let’s discuss oil change intervals, and why you could be wasting your money.

What the Manufacturers Recommend

If you are going to a reputable source for your oil and lube services (we are repudiating 10 minute quickie quickie oil change locations), they will be using the correct spec oil that your vehicle requires.

The majority of manufacturers recommend between 8-20,000km oil change intervals. The manufacturers have studied their vehicles, put them through rigorous testing and whatever mileage they set for their vehicles is what they conclude to be a “good” interval.

What’s Commonplace

We have seen many people either closely adhere to the service sticker on their windshield, or stick to a pre-conceived interval they have been changing their oil at for ages and nothing has gone wrong.

We have also seen instances of people ignoring oil service completely, and, well, let’s not discuss that right now…

What We’ve Found

In our experience, we have used high-quality, European oils such as Total, and Liquimoly (Liquimoly now being our preferred brand), and we have experimented with our own vehicles as to what the best interval is. That being said, we are testing on Volkswagen’s and Audi’s, but this goes well with pretty well any vehicle brand.

We have pushed the limits of the “recommended service interval”, and have found that, in the case of VW and Audi, it’s simply too long.

In our experience, we believe we have found a sweet spot (Again, for VAG vehicles). 10,000km*. Why you ask?

*For Non-VAG vehicles if this exceeds the recommended interval, DO NOT EXCEED

With modern filters and oils, 10,000km seems to be a perfect medium, where the oil still has life in it, and, most importantly, the filter is still healthy.

We have previously posted about filters, so we won’t get into extreme detail. If filters are left too long, the filtrate material either begins to clog, loosing its effectiveness, or the material begins to constrict, reducing filtration capability. If left too long, even high quality OEM filters, the filter will not be able to perform as effectively as before, and could allow contaminates into your engine.

Contaminates are no good for your engine, and can lead to premature wear and tear, and engine failure. Another issue with constricted filters, is a reduction of flow, reducing the effectiveness of your lubrication system, causing it stress, and of course eventual failure.

This is speaking of course of high quality synthetic oils. What if you are using non-synthetic oil?

We recommend 5,000km for best results. Again, if this exceeds the manufacturers interval, do not go beyond the recommendation.

TL:DR Version

To summarize, we recommend following the manufacturers specified service interval. In our experience, we find the 10k+ intervals too high. 10k seems to be a great medium for oil changes (with full synthetic, non synthetic 5k), the oil still has life in it, and the filters aren’t restricted and are still able to filter effectively. Also, if you are unable to reach a service station right at that 10k mark, you still have some life in the oil and filter.

This is simply what we have found. There is nothing wrong with changing your oil a little earlier than the manufacturer recommends. There is also nothing wrong with changing your oil at the specified service interval. Mainly, what we want to stress is never go over. Waiting too long for an oil change can lead to sludge, and engine failure.