I like his videos, and don't distrust his opinion, I just don't see evidence for his judgment on this one.

Personally, I'm not opposed to anything anyone else does. Your car, your choice. I'm just not convinced that it makes any difference with modern engines, and especially longer lasting synthetic oils. I've even had oil tested at 30k before and the results came back fine. Not that I would do that personnally.

Of course more frequent changes don't do any harm, whilst excessive intervals certainly do, so we all make our own choices as to what's best. I choose based on the recommenadtions of both engine and oil manufacturers, along with personal experience, and therefore see 5k as a somewhat arbitrary number. After all, there are still some who do 3k changes and think 5k is too long. As a result, we're all just choosing where we draw the line.

I would also agree that, whilst it's entirely possible that engines can do 300k on 10k changes, some might develop issues which they might have avoided with more frequent changes. The trouble is that I have no idea or evidence to suggest what that frequency might be, or even the odds of having an issue. It might be 5k, or might be 3k, or even 1k, so you end up chasing an unknown number, to try and beat equally unknown odds.

As such I chose 10k for broadly similar reasons that you might choose 5k. It's a number we feel comfortable with, with little actual proof of whether it will make our cars last longer or not.

So, no opposition from me if you choose shorter intervals, just a difference in what I choose.

That said, I imagine it's an easier choice for those who have the time, tools, space and inclination to do it themselves.

 

Well in fairness that applies to both sides, in that there are those who need to justify why they do more frequent changes.

Whilst it might be obvious to most that more frequent oil changes provide benefits, it's not at all obvious as to whether a switch from 10k to 5k delivers those benefits. By that I mean that any posssible harm that might come from 10k changes, or benefit from 5k ones, might be so negligible that it doesn't matter. Meaningful harm might not occur until 15k, 20k or 25k miles, and meaningful benefit might not occur until one does 3k or even 1k oil changes.

As I said earlier, I've not seen any data to show that 5k oil changes cause engines to last longer than 10k oil changes, and so both are just arbitrary numbers. So, whilst I don't mind spending the money, I'd prefer to have some data to back up why I'm spending it, and at what point that expenditure makes a meaningful difference.

As such, as I also stated earlier, in the absence of any proof, it seems no more logical to change oil at half the manufacturers recommendation than it does to change tyres, coolant or brake fluid at half their life.

 

The data is to do oil analysis and see how oil does for your specific driving conditions. People that do a lot short trips in cold temps and idling in traffic do not fall into “normal driving category” and may need to change oil sooner than 10k. Without testing your oil you can only guess. Toyota 10k is for normal driving, they dont say anything about severe conditions unfortunately

 

The (US) 20XX Lexus ES 350, ES 250 Warranty and Services Guide actually does say something about severe conditions maintenance intervals. From the Guide:

 

Very long OCI has been proven to cause oil control rings to seize and cause excessive oil consumption. It's blatantly obvious when you tear down the engine. That doesn't mean ALL engines will experience this but many have and will.

Doesn't matter how good the oil is, short trips mean condensation mixes with oil that's how sludge and eventually rock hard carbon is formed.

 

“If there’s a chance, just a chance, that more frequent oil changes can extend the life of our engine, is that not worth an $50, $100, or $200 a year?”

Changing the oil every time you fill up the gas tank would be even better then. Isn’t that worth an extra couple thousand dollars?

 

Please change your oil every 10K. I need more cars in the salvage yards to harvest body parts from.

 

Lets not exaggerate, owner manual recommendation of 5k for severe service was shown here.

 

Obviously. See, you do understand.

 

Guys, change the oil whenever you feel it is good for you and your engine.

Myself, I do it every 5000 miles and I found some benefits out of it.

 

That's true, and I have done oil analysis on a car that had gone 30k without an oil change, and it came back fine. I imagine that was due to it being largely highway miles though. I also agree with you that oil change requirements will differ according to driving conditions, and that severe conditions require more frequent changes. I think they do mention that in the manual.

 

Oil analysis can be useful of course, but what about the things it doesn't measure (because it can't)? Does an oil analysis measure sludge or varnish, or dirt, or that your piston rings are about to stick and start consuming oil?

I spent many years as a fleet mechanic and it made me very conservative regarding things the manufacturer tells their customers - especially service intervals. It is hard to forget the car maker has much different priorities than we owners do and the car maker's top priority, once their product is out of warranty and repairs are no longer on their dime, is now selling you a replacement product as soon as possible.

 

Fair comment, but it does tell you the levels of contamination in oil, which in turn will help in identifying what, if any, wear might be occuring in engine components. It will also tell you the condition of the oil and whether it's still able to do its job. That said, excluding specific instances, I'm not aware of any of these problems occuring more frequently in cars that have done 10k changes over 5k ones.

I also agree with you about manufacturers, but some are now offering 10 year warranties, extendable to 15 years (for Lexus in the UK), whilst recommending 10k/12 month oil changes. In addition, it's oil companies who are also saying that their oil is good for 10k, which results in them selling less oil if people follow that. It's also hard to forget that dealers, mechanics and garages have different priorties too, and that a 6month/5k oil change is a much better proposition for them. In the end it can be vey confusing for the consumer.

Don't get me wrong, I don't dispute that more frequent oil changes can be beneficial for an engine, and am only wondering at what point is it oversold? By that I mean I've yet to see evidence that 10k intervals cause any meaningful harm, or that 5k changes are meaningfully better. As it stands, there might be a huge difference between running oil for 30k miles and 3k miles, and little to no difference between running oil for 10k or 5k, but there doesn't seem to be any data that points to where the tipping point may lie. Obviously it also depends on the oil used, and so I'm referring to synthetics that are designed for longer OCIs.

I honestly have no idea what the reality is, and completely understand why people would feel that more frequent OCIs are better, and am just curious to know if there's any data that shows the differences in harm/benefit between 10k & 5k changes. Without that it just seems like feel good guesswork to me, and not much different to saying that you'll live longer smoking 20 a day than you will if you smoke 30.

In any event, best of luck whichever you choose.

 

yes, UOA does not have full picture but its better than doing nothing and just keep quoting owner manual or other tales of how you trust toyota and etc.

 

i agree with you...with the 5k intervals, wasn't that based on using conventional/standard oil? if the debate is really 5k vs 10k interval, isn't there a benefit by going with a better quality synthetic oil? if i was using dino oil i would for sure stay on 5k, but with synthetic tech, it lets me sleep at night with a 10k oci