10K oil changes are BAD! ??

With the valve cover removed, you find it in the front cam bearing cap.

 

Do you have a part number?

Still, it's much easier to do frequent oil changes.

 

I wasn't able to find one. It's not shown on the cylinder head parts breakdown. That bearing cap is illustrated but not offered for separate sale, as it and the camshaft housing sub-assembly are machined together.

 

Over 200k 5k syn oil changes result in another 20 oil changes. For me using oil i buy from walmart and a toyota catridge is less than $30. So we will say $30. Up until last year it was $20 but inflation finally got us. So anyways $30x20times = an extra $600
As said many times a lot of things disqualify you from the 10k service and put you in the 5k service. Why try and save $600 to risk needing to replace your piston rings early or for most people a short block at probably around $5000-7000 dollars. The risk versus reward ratio seems dumb. Toyota has had piston ring cloggin problems with more than half of their 4 cylinders for the last 25ish years almost.
Reminds me of just running state minimum insurance vs appropriate coverage.

 

All of these questions can be answered using technology and not some made-up time or mileage number.

You can get an oil analysis kit and send in a sample of your dirty oil and get facts about its condition
and a recommendation on how long it could have been in service.

 

5000 miles from the oil change and 2,5 months. Oil is Mobil 1 ESP X2 0W-20. Car is mainly driven 30 miles one way (or longer distances) with moderate speed at 60mph. Practically no city driving, maybe 2% of the distance, 95% of driving is only the driver inside. So, for me the best possible conditions of use of the car to minimise the wear and tear of the engine and oil..
I do NOT plan to replace this oil which is by my view (only view, no further testing done) still in excellent condition. I will recheck again at 7.000 miles. I am planning to go for 9.200 miles service. But, I will see in what optical condition the oil will be at 7.000 miles.

 

I lied (or I looked before they updated something, but probably I just lied).

It is callout 15678A in this cylinder head diagram.




2010 Toyota Prius Filter, oil control valve. Engine - 156780V010 - Genuine Toyota Part


I would not recommend anyone disassemble their engine down to the cam bearing caps for the purpose of checking this little screen, if there isn't some other good reason for that kind of disassembly. Certainly not as an alternative to more-frequent oil changes.

 

I don't see where a full synthetic oil can't go 10K miles when the vehicle is a hybrid driven normally, as the engine isn't running all the time anyway. Someone show me the oil testing results to prove me wrong.

 

Maybe no one's interested in proving you wrong. Maybe the need to be "right" should be weighed again the need to avoid risk, and the consequences, say engine failure.

OTOH, if it's an Uber vehicle, you're gonna trade it in a few years, and there's no love lost, then yeah, sticking to the US schedule is the way to go.

Besides all that, I'd consider:

Toyota's historical stance on oil change interval. For second gen Toyota USA said 5k miles or 6 months (whichever comes first), with 5W30. Going to 10k miles or 12 month, with 0W20, which is one heck of a jump.

Look around at other manufacturers. Honda's kinda weird, stopped publishing a schedule, says follow the "Maintenance Minder". In my experience that worked out to around 9k kms (5~6k miles), at varying months. One other I currently know, is Mazda Canada's schedule for CX-5: 8k kms (5k miles) or 6 months, with 0W20.

FWIW, with 3rd gen, while the Toyota USA made the aforementioned jump, Toyota Canada sat tight with 8k kms (5k miles) or 6 months.

 

I changed oil 10k+ miles using mobile 1.
I took the engine apart at 250k miles after blowing the head gasket due to an EGR clog.
The engine looked perfect inside.
Enough proof to me.

Posted via the PriusChat mobile app.

 

That sounds more like one of the first few posts in a thread like this than the 188th.

So, probably the right spot for a reminder that officially, if you look in your scheduled maintenance guide from Toyota, you will see several criteria for the kinds of driving you do, and you will see that the official change interval for you is 5k, unless you can answer no to all of those, and then it's 10k.

Da capo al fine....

 

Maybe less so that it superficially appears, because that jump was accompanied by effectively beginning to require synthetic oil

Toyota jumped in the opposite direction a couple of decades ago after they got into trouble with frequent sludging of non-synthetic oil used as long as they had suggested.

 

Well yeah, with "effectively". The word "synthetic" only appears in reference to upholstery material, in the Owner's Manual. But it could be argued, changing the spec to 0W20, that weight's pretty much exculsively synthetic. Still, a bit conflationary?

FWIW, 3rd gen spec with 0W20 was still 8k kms or 6 months according to Toyota Canada, and similar story for Toyota Australia.

I'd rather waste a bit of oil and $'s, changing mine at ridiculously low kms, every 6 months. But yeah, it's up to the individual owners.

Addendum: to muddy the waters even further, with the advent of Toyota switching oil spec to 0W16, they now advocate if 0W20 is used, to switch every 5k miles or 6 months (similar the previous severe service interval they designated for 5W20). Which leaves me incredulous, suspicious of their science.

 

Pictures or it didn’t happen!!!

 

You would be one of the only ones. Lets see that piston ring shot. I wanna see the oil control rings and the cylinder walls

 

I can believe the cleanliness and bearing wear looks good at tear down.
I question how one can point to 'Clogged EGR' as THE REASON the Head Gasket went bad.
And that's all I question. Hang on.....

5k or 10k.
It's gospel. No other in-between interval is allowed by the Big T.

Guys, it used to be $15-20 to get an Oil Analysis done on your old oil.
That leaves out the: Look, color, smell, feel, taste tests posted here....

?Do you take pictures of all your exact 5k oil change intervals? "Pictures or it didn’t happen!!!"
Relax Pal, why would he lie?

OK, good point.
So what if the oil control ring lands have clogged up 'drain-back holes' in the pistons.
That would cause higher than normal oil consumption. What else do you think it would cause?
How would that be related to the head gasket failure?

 

Faster you clog the piston rings the more oil you wont control and the more blowby the crankcase will be subjected to. So you will burn oil through the increase in blowby pushing more oil vapor into the intake, and the oil control rings allowing more oil to be burned because they clog up and lose their ability to pull the oil back off the cylinder walls into the crankcase over time, also you will get the ring seize and reduction of compression over time on top of regular wear. Bottom end they always look good bearings wise, so the big wear item on these motors you want to worry about is taking care of the rings. The bummer is the oil consumption leads to a faster clogging egr, and it clogs the tips of the fuel injectors over time as well as the intake valves and valve seats. So the combustion mixture starts to get pretty far out of wack. Then you get the knock (think knock sensor not rod knock) everyone claims to feel but doesn't get a check engine light for, and then when they do its usually a cylinder 1 or 2 misfire meaning the head gasket has been pinged to death. Burning oil is pretty much just bad all around (and catalytic converters don't like it either and those things $$$$)
There's multiple solutions but to start change the oil every 5k at minimum, and do something about the EGR system before 150k. Either clean it or disable it.

 

I assume you mean the mixture is different between cylinders.
The O² sensor is supposed to keep the overall mixture where it should be.
Why is the Knock Sensor not keeping knock from happening, like it was designed for?
Why is 5k miles the magic number for ALL?

I have a friend that drives his Prius 10-12 hours at highway speeds on the days he works.
His oil seems fine at 10k miles. I won't tell you how long he'll go on an oil change in the summer.
(And, as always, there are Oil Analysis kits for not much money to settle this subject.)

He has done at least one 'Ring Soak' using the correct product and letting it soak past the rings over the course of a few days. He says that definitely improved oil consumption!
(He has a few Gen3 and Gen2 Prii. Most are in the 400 - 600k mile range. Yes, one Gen3 has had the head gasket replaced with the FelPro version. Only time will tell if that is a solution. Gen2 engine has a good design for the head gasket, evidently.)

But now you say I can disable my EGR system, (with a plate at the intake port?), and be guaranteed a head gasket that will last like a normal engine?
I'm listening!!!

 

^ concur

^ disagree

 

That is a good question, and I don't know the answer, but there probably are people who do.

Some of them might be on the Toyota team that designed the ECM firmware and the EGR system.

They designed that firmware specifically to back off the spark timing if an EGR malfunction has been detected. They don't wait for the knock sensor to trigger it.

Maybe their thought process is something like "if we already know we are creating conditions conducive to a damaging effect, let's not wait to see the damaging effect in its full glory before we change that."

Maybe some of those engineers could be sent to Exxon.