Frequent oil changes will make your engine last longer…. period!

Ever heard this joke? 

Q: “How long is a piece of string?” 
A: “Twice the length from the middle.” 😀 

If you ask someone (or google/search the internet) about how often you should change your car’s oil, you’ll likely get an answer as ambiguous as the joke above.

Why asking about engine oil change frequency is never a straight answer?

There are numerous factors at play:

  • The type of oil you’re using (conventional vs. synthetic).
  • The oil brand and any additives.
  • The conditions under which the engine operates (e.g., temperature, humidity, exposure to dust, sand, salt).
  • The car’s age and its past maintenance.
  • Whether the oil level has ever run low.
  • How often the oil was changed previously. …and the list goes on.

Truthfully, there’s no one-size-fits-all answer. A lot depends on your objectives and how/where you drive. Are you racing your car on a track? If so, you’ll get different advice compared to someone driving primarily for fuel economy.

So who is this for?

To narrow down the scope, let’s frame the question regarding engine oil change frequency as:

“I own a performance vehicle and aim to protect my engine while achieving maximum performance.”

While we won’t dive into which specific oil to use (that topic alone could fill libraries!), let’s assume you’re using the factory-recommended oil for your engine.

The short and simple answer to how often I should change my engine oil:

For those seeking a straightforward response: as long as you maintain the engine within standard operating conditions (oil level not reaching the ‘red’ mark and water temperature staying within the standard range), changing the oil every 3,000 miles is likely the best guidance. However, for cars that see infrequent use, changing the oil at least once a year is advisable.

OK but I want to know if that is a waste of money or not often enough?

For a more comprehensive answer without diving deep into details: adhere to the above, but also consider an oil analysis annually or every other oil change. Companies like Blackstone Labs or Wix offer such services (rokauto is a great place to pick up oil sample kits). Personally, I get an oil analysis with every change because I prefer detailed insights over time. For instance, with my BMW M5 S85 V10, I’m keen on monitoring my rod bearings!

Understanding every aspect of the oil analysis might be challenging. The brief summaries provided by these companies can offer crucial guidance regarding engine oil change frequency. In essence, an oil analysis is the most definitive way to gauge if you’re changing the oil at the right intervals for your specific oil, engine, and driving habits. In the industrial sector, routine oil analyses are standard practice due to their importance.

What else can an oil analysis tell me?

Beyond just checking oil health, oil analysis can also detect other engine issues. In the past, such tests have identified a failed head gasket for me (evidenced by coolant in the oil), fueling issues (like running too rich or having faulty rings – fuel detected in the oil), and many more. Additionally, these tests can provide feedback on the oil you’re using, potentially offering insights into whether it’s offering adequate protection for your engine.

E60 Differential Oil Change is Easy!

Based on the color of the oil and the content of the Blackstone report, this change was way past due. The differential had no leaks, and thankfully, wasn’t making any noise. This is one thing that you need to check when buying an M5, as a replacement can be costly. 

The only thing you have to be careful about is using the right torque for the plugs. There are two different types: one with a washer and one with an o-ring. It’s only a 5NM difference, so it’s not the end of the world. 

The oil change kit came from FCP Euro, and interestingly, it had a Mercedes sticker on the bottle. I guess if it’s good stuff, it’s good stuff 🙂

Don’t delay, change the oil on your BMW E60 M5 V10 Differential today!

FCP kit link. Part number from FCP is: 33117525064KT6 – Contains 3x500ml bottles of 75W140 Castrol Syntax LSD Oil and two differential plugs (OEM part number 33117525064). OEM differential oil is 3-4x the price. The OEM part number for the oil if you’re interested is 83222282583.

You will need a 14mm hex socket and a torque wrench capable of 65NM. Gearwrench have a socket that is widely available and has the part number 80662. Amazon of course has a bunch available that are cheaper. There are some lower profile ones which might work better with the exhaust. 

Video link 

E60 S85 M5 PCV Valve Replacement 

During one of the previous videos, when the M5 was being aligned, we discovered a leak around the rear main seal area. However, this isn’t always caused by the rear main seal, so we had to trace the source. The video demonstrates where the leak was originating from and provides instructions on how to replace the PCV valves.

This video illustrates where the leak was coming from and how to replace the PCV valves. 

One day, hopefully, I will be able to drive the M5 without having to work on it 🙂

Video link