The Car Care Nut is of course a guy that spends all day every day on Toyotas and Lexus and he's surely seen everything twice by now. And I concur with more frequent oil changes for any car I care about, although I admit during the last years of my mom's life, when she could no longer drive her 1999 Mercedes C-Class, I only changed the oil twice in the 5 years I was responsible for it. I had absolutely no interest in owning it myself - the A/C was broken, none of the power windows rolled up on their own power, and it only had a 4 cylinder engine with 111,000 miles on it - and it was just destined to be sold off (I got $2500 for it a few months ago). So I wasn't about to spend $300 on a Mercedes service type oil change.
However, my own cars have their oil changed every 3 months. I worked for a government fleet for a long time, tore down and fixed my share of engines, all of which got maintained "by the book" i.e. the manufacturer's intervals so I saw the results of same during long term use/abuse and it made me a big believer in simply ignoring "recommended intervals" at least for oil changes. In general the automaker only wants you to maintain it just long enough to exceed the warranty period. And after that their priority changes completely from ours (they want to sell you a new product, or at least expensive repairs, NOT engine service).

Changing oil in an engine every 3 months is a total waste of time and money. This isn't 1968 and the synthetic oils of today are greatly superior to those of yesteryear. 60 years ago the recommended change interval was every 3 months or 3000 miles... Not necessary today with virtually any car and an interval change such as this is just wasteful and harmful to the environment. Additionally, auto manufacturers WANT you to be satisfied with your purchase and build dependability into their products to accomplish this and recommend the appropriate OCI.:nono:

I do all of my own maintenance on my vehicles and I have always started this at the end of the Toyota and Lexus freebies services. I generally follow the manufacturer's service interval recommendations for severe service, just to err a bit on the conservative side. With today's more sophisticated synthetic oils and fluids, I feel you are generally okay with the normal OSI but, I just feel better doing things more often. Also, I don't put as many annual miles on any of my vehicles at this point in my life and changing the oil every 5,000 miles is a good idea, as that is close my annual mileage. With my new 2024 Lexus RX450h+ I plan to do this at 1,000 miles, as the 5,000 mile free service at the Lexus dealer is basically just a tire rotation. I may have to do another one before the 10,000 mile service rolls around, as that will be my only dealer oil change.

Oils today are more durable than 30-40 years ago, but there’s something that no oil can escape from and that is the fuel dilution on cars with GDI.
That is one of the reasons why we should do 5000 OCI.

Good point, and I think such operating conditions probably just fall under "severe service". And truth be told that's pretty much how everybody drives. The main problem with going with long change intervals for a car that only gets 2,000 miles a year are oil oxidation, fuel dilution, and water dilution. All oils begin to oxidize immediately you open the bottle and the anti-oxidants added by the oil refiner do not last forever, they degrade over time. Also every time you start the car you are diluting the oil with a certain amount of gasoline, plus water in the form of moisture. And if the car doesn't get warmed up and driven for a while that gas and water doesn't get burned off by the PCV system so it just accumulates in your oil.

The reason that is a bad thing is immediately apparent to anybody who has ever seen the inside of a disassembled engine: most of the metal inside, including the cylinder bores, the crankshaft and rod bearings, and the camshaft is unfinished bare metal. This means those components are totally unprotected against corrosion by anything except for the engine oil. The oil takes a while to completely run off the bare metal parts but run off it does, and the longer it sits the drier they get. This is not a problem for a daily driver since the oil film is continually renewed and most of the moisture burns off each time the car is driven so corrosion is generally not a big problem on cars driven all the time. But for cars that sit idle for weeks and months, this can be a serious consideration especially in humid climates... everybody has seen or heard of engines that seized up from sitting too long, and the reason is almost always internal rust.
(I knew of a guy that was going in the service and had to leave his car unused for an indefinite period and didn't know when he'd be back for it, so he decided to "pickle" the engine. That is, he decided keeping the internals soaked in oil would prevent corrosion. So he filled the engine all the way up with oil until it could literally hold no more. The idea being if all the parts were completely soaked in oil, the engine parts wouldn't rust and seize up. Unfortunately I wasn't around when he retrieved the car and had to reverse the process, so I don't know if the pickling actually worked; but that's one way to keep an engine from rusting!)

A fair point and in most cars I think that is indeed what happens. The way most Detroit iron and German autos are designed, the owner doesn't dump the car because the engine wore out. Instead what generally happens is something else that is really expensive breaks, and it's the last straw for the owner, who then trades it in for another car.
But one of the reasons we bought our Lexus in the first place, is because of their extreme durability. So I think for our cars it makes sense to over-maintain them. Because unlike some designed-in defect Detroit crap-mobile, we'll be rewarded by long and trouble-free service at the end.

Well, first, that's NOT how pretty much everybody drives. More importantly, nobody in their right mind goes for long mileage oil change intervals if they drive just 2K miles per year. Instead, under normal conditions, which we can assume most people DO drive under, you change it once per year OR at 10,000 miles, whichever comes first. Right? Right.

That said, as an owner of a 2023 ES 350 thinking about service intervals, this thread has been entertaining. I enjoy the Care Care Nut, but it's important to distinguish between fact and opinion. That dude gives a lot of opinions that I take with a grain of salt. His factual mechanical knowledge, though, is trustworthy IMO.

Yet AAA study found that roughly 60% of cars fall into severe operating conditions as defined by manual. But of-course everyone thinks its not my car, its someone else

Do AAA provide any stats on what percentage of engines fail with 10k changes, compared to 5k changes, as that's really the only definitive stat and the rest is gueswork. I get that manufacturers only care about a car until the warranty period ends, but over here Lexus offer extended warranties up to 15 years and only require 12month/10k oil changes to maintain that.

I also understand that most engine wear occurs at start up due to the initial lack of lubrication and engine heat. Not sure about other cars, but in the case of Toyota/Lexus hybrids, the engine is spun up by the electric motor and pre lubed before ignition, and is then brought up to operating temperature faster, which to some extent mitigates the effects of shorter trips.

There are possibly cultural reasons for different opinions too. Here in the UK, and most of Europe, we buy a car, get it serviced every year, and that's it. As long as the required maintenance items are attended to we don't experience too many unexpected failures. In the US there seems to be more interest in doing one's own maintenance than here which, coupled with cheaper oil prices, marketing and the preponderance of quick lube shops (which we don't have), more frequent oil changes have been considered the norm. Ask a garage or dealer to do 5k changes over here and they'll look at you like you're crazy.

no, there are no stats because most of the cars are sold multiple times before they hit 200k miles and at that point maintenance history is unclear.
according to Lexus manual, if you operate under severe conditions the oil change is 5k miles or 6 month.

But the AAA study's severe conditions are different than Lexus's severe conditions listed in the Lexus ES 350, ES 250 Warranty and Services Guide.

For example, AAA's severe conditions includes "Drive in hot weather stop-and-go traffic"; whereas, Lexus's severe conditions doesn't include that condition. For southern California drivers where the AAA survey was conducted, that specific severe condition is pretty much guaranteed for all but a very small minority of drivers. (There are other differences in severe conditions definitions between AAA's and Lexus's definitions. This example is just the easiest, clearest condition difference chosen to highlight the fact there are differences in severe conditions definitions.)

While one might argue the AAA study's severe conditions definition should apply to Lexus ESs, it is going a tad bit too far to claim AAA's definitions are "as defined by [the Lexus] manual".

lexus severe driving conditions are pretty much the same as for any other cars: Short trips in cold temps, excessive idling, a lot of stop and go traffic

This is the proven in the real world way to get 500,000+ miles out of a late model Camry/Avalon/ES350 with a 6 or 8 speed transmission:

https://cimg9.ibsrv.net/gimg/www.clu...118a069b8d.jpg

That's great if you use the car as a taxi or limo. Avg Joe who drives 15K miles/year ain't keeping the same car for 30+ years:)

I would agree with you that more frequent oil changes might be required under certain circumstances. Not sure what AAA consider severe, but Lexus state special circumstances that require 5k changes as being driving off road, towing a trailer, repeated short trips under 5 miles in below freezing temperatures, and extensive idling. Of course some will meet those conditions, but probably not the majority. Other than that, cars that are specced for synthetic oil require 12month/10k changes, and those that run on mineral oil 6 months/5k.

Ulimately, assuming one at least follows the maintenance guidelines, then there's probably no right or wrong, so I guess it's largely a matter of being aware of your own usage and personal preference.

Is that a Camry or Avalon cluster? Certainly not an ES.