For those that advocate 10K miles OCI

Author's theory is that you need the bits of
clutch debris floating around to help your transmission shift without slipping is a necessity.
I highly doubt this......... The transmission does not rely on clutch debris. Transmission fluid exists for a reason.
 
What kind of vehicle were you doing 60k oil change intervals on with no ill effects???

I thought even OTR trucks maxed at like 30k intervals on full synthetic and a 20 gallon capacity. I am NOT very familiar with maintenance for that industry though.

40,000 mi conventional oil changes.
(Standard published interval was 15,000 mi)
Typical UOA Numbers
10 gal sump / 2 gal of add oil
6.0 mpg Avg
Cruise Turbo PSI - 6
Max Turbo PSI - 30
Oxid: 15-20 (Max 25/30)
Nitr: 10-15 (Max 25/30)
TBN: 5.2 - 6.4
Soot: 0.2-0.4% (Max 2-3%)
Note: Condemnation limit changed by engineers during engine life.

First major engine work was 1.2 million. Head gasket leak due to liner walk.

The only real difference I saw with G3 Synthetic was a slight drop in oxidation numbers and it raised the max allowed soot limit. BTW the big 3 looked almost exactly the same in testing other than additive package signature which lends credence to oils built to meet the same spec being a commodity.

60,000 mi is now standard interval for conventional for some engines.
 
Last edited:
In this case Toyota's Transmission Fluid at other than 60K miles or more. Author's theory is that you need the bits of
clutch debris floating around to help your transmission shift without slipping is a necessity. Change it too early and you
don't have enough "helpful" debris available to shift those clutches, hence more slippage, and then an earlier end of life on the trans.
This is independent of the car's mileage. Really???
I assume that you're referring to the Scotty Kilmer video that he shouts when changing ATF can be "bad". where the ATF has been in use for well over 100,000 miles... where the clutches are so worn, that the friction material in the old ATF is what is keeping the lockup operational.
 
You can find a situation that supports almost any position. BFD. It always seems to come down to what an individual believes will work well for them.

I've not seen (at least I cannot recall) anyone being swayed from their position regarding OCIs by any arguments contrary to their position and belief made in any of these threads.

Has anyone changed their position on OCIs for their situation by what they've read here?

Sure, in the 20 years I've been here I've come to the conclusion that approximately 1/2 mi and a minute or so of idle time does not make a short oci and 60,000 mi does not make a long OCi. It needs, what it needs. In the first example the lubricant is absolutely destroyed and if it was physically possible would likely already have been changed at least twice. In the second it isn't even half way to the correct OCi

Don't concern yourself with a number you reached by throwing darts. Follow the data.
 
I highly doubt this......... The transmission does not rely on clutch debris. Transmission fluid exists for a reason.
Yeah I did my first drain and fill on my Accent at 127k and between then and 187k it's been given about 13 d&fs, shifts great with pure ATF, no clutch debris required.
 
First time I can ever recall someone saying that changing a fluid "too early" is BAD for your vehicle.

In this case Toyota's Transmission Fluid at other than 60K miles or more. Author's theory is that you need the bits of
clutch debris floating around to help your transmission shift without slipping is a necessity. Change it too early and you
don't have enough "helpful" debris available to shift those clutches, hence more slippage, and then an earlier end of life on the trans.
This is independent of the car's mileage. Really???

So my 2001 Lincoln Continental (FWD) is known for having an under-powered "6 cyl Taurus trans" (AX4N) that do tend to
fail somewhat early on. Factory recommended fluid changes are at 30K which is probably fine for highway cruising. I had a highway cruise Lincoln AX4N that I changed every 25K miles and took it well over 200K miles before the engine died. But, what about cars doing mainly
shorter trips and stop and go around town, frequent auto transmission shifting..... that is much more severe service on a transmission? Per the author, changing the fluid early at say 15K to 20K that would be significantly shortening Lincoln AX4N transmission life.

That's a new take on trans fluid theory that I've never heard before. So here I was planning on doing my next trans fluid change at 20K miles
to avoid any risk of overly oxidized trans fluid......and now it's supposedly the wrong thing to do?

No Sir. Your original instincts for changing the transmission fluid early are correct. I take a similar approach with the 4T65E Unit in my LeSabre. ATF fluid changes have been done regularly and properly since the car was new and that is exactly how it should continue to be serviced. The “concept“ of clutch debris as a friction assist is only relevant (in theory ) for transmissions that have gone their whole lives, well over 100,000 miles for example, without any transmission fluid changes at all. In those situations, in theory, it might be the case that the transmission is so worn and neglected that this clutch material might be helping in some useful way, but by that point, the transmission is definitely on borrowed time. So definitely, go with your original thinking that regular scheduled fluid and filter changes are what can help transmissions like the ones you and I have live out their maximum lifespan.
 
I watched The Car Care Nut's latest video. I've got to say, if he didn't go through the specifics I wouldn't belive him either. However, when he mentions the oil analysis and shows the bearing (which looks PERFECT) then shows the cylinder worn due to the oil rings locked up it certainly does make one scratch their head. He even says in other videos, it's not the 60-100k miles that's an issue. It's 120k miles on up when the issue(s) really come to light. Which as he says is usually way past your warranty and extended warranty.

 
So this is the video you couldn’t upload 6 months ago so now you upload again and then create the same exact post?
I don't see how that's even possible since it was just released 7 days ago according to his YT channel.

1659825287489.webp
 
Basically he wants anyone who owns a Toyota to do 5K mile oil change intervals. Regardless of the fact that Toyota says 10K, he says do 5K intervals and you won’t have problems like this Dr who had a long daily commute to and from work and used bulk oil from the dealership with 10K mile intervals and didn’t use M1, Valvoline, Castrol, Amsoil etc…
 
Basically he wants anyone who owns a Toyota to do 5K mile oil change intervals. Regardless of the fact that Toyota says 10K, he says do 5K intervals and you won’t have problems like this Dr who had a long daily commute to and from work and used bulk oil from the dealership with 10K mile intervals and didn’t use M1, Valvoline, Castrol, Amsoil etc…
The question is what bulk oil is used by Toyota dealerships? Honestly I don't think anyone trying to drive a car 200-300k plus should really be doing more than 5k, you're spending very little extra money as insurance you won't need a $6000 engine. Nobody ever wore out their engine cause the oil was too clean.
 
The question is what bulk oil is used by Toyota dealerships? Honestly I don't think anyone trying to drive a car 200-300k plus should really be doing more than 5k, you're spending very little extra money as insurance you won't need a $6000 engine. Nobody ever wore out their engine cause the oil was too clean.
Why do you think at 10k miles the oil is unclean?
 
Back
Top Bottom