Engine Oil and Trans. Fluid Change Intervals

I would argue that replacing items 2 or even 3 times before they are worn out is not the best way to save money. It’s not like there is a history of this transmission having premature issues. There’s 14 years worth of data here.

 

To me and many others the drain fill is the better option. That’s what I have done with every vehicle I have owned and never had any transmission issues.

 

it doesn’t matter.

Drain and fill is absolutely silly. You people want to sit here and mix fluids more frequently rather than just do a full exchange.

and you sitting here advocating that “particulates” keep a transmission together is complete bullshit and shows you have no idea what you’re talking about, or that you’re just so old school you keep spreading old outdated myths.


if your transmission is being held together by “particulates” then a fluid change is the least of your worries.

 

The only thing silly here is you for not understanding how an automatic transmission works.

 

says the guy who hasn’t changed his fluid in 115k miles.

 

It’s working flawlessly along with my Tacoma that will hit 200K next month and the Cherokee I had before that and sold at 180K.
How many miles do you have on yours?

 

And this is why no one should listen to you. Lmao.

 

People can make their own decisions. Hopefully they don’t listen to your advice to do a full flush at 100K though because that’s the worst decision for your transmission.

 

there you go showing you don’t know shit.

a fluid exchange is not a flush.

now keep running your 200k fluid while giving advice

 

Good luck in life bud. I’m sure it’s going to be tough for you.

 

This is a good video from someone who really knows what they are doing when it comes to Toyotas.
https://youtu.be/jJr30r6RRgw?si=Cq9BqG2B1-qhHWCk

 

Out of an abundance of caution. The first engine oil change at 1400mi showed high wear metals. Both diffs had accumulated some mgnetic sludge when I changed the fluid at 17k. TC looked very clean however.

 

The old fluid being critical more a worry to be concerned about when a transmission has been neglected. At some point the old fluid helps keep it together but at that point the transmission is on semi-borrowed time anyway.

Until then, I wouldn't consider there to be much difference between an exchange (using internal fluid pump over an externally-powered flush) and more frequent drain/fills. Granted, if the 4Runner's transmission would go 250k without a change before dying like some random anecdote then that's not so bad.

I just like to cross my t’s and I’m figuring that should I decide to stretch intervals I’d start after the factory fluids have been freshened up.

I’m just some random yahoo on the internet dispensing opinions of widely varying validity though.

 

Exactly. Was wondering when Mr.Nuts videos would be referenced. Along with Tinkerer’s Adventure both are great resources for all things Toyota / Lexus IMO. Lots to learn off those channels. CCN for things OEM and TA for any off road modifications.

 

So oil mixes with water. I've never seen that before.

 

https://www.machinerylubrication.co...ygroscopic and as,the oil are in equilibrium.


"Oil is hygroscopic and as such will draw water directly from humid air above. For instance, if the air has a relative humidity of 80% then a hygroscopic oil in contact with the air will absorb water from it until it is also at 80% relative humidity. At which point the air and the oil are in equilibrium."

 

Engine oil molecules are hydrophobic.

Pour a quantity of water into a glass container. Mark the fluid level.Nkw, pour a quantity of oil into the container. The oil will float, it will not mix. Let the liquids settle for a week and see if the separation is still at the line that you placed on the container.

 

In regard to engine oil, the biggest problem is water that will collect inside the oil pan from condensation. In cold temps, running the engine for short periods of time will cause lot of condensation inside the crankcase, and water literally will build up inside there. Because the water will sink to the bottom of of the oil, the next time you start it, the water and oil will mechanically mix. If you get enough water, the oil will emulsify, and you get Mobil1 Mayonnaise.

That’s a big reason to never run the engine on stored cars, or rarely used cars, just to “circulate the oil” for a few minutes. Especially in colder weather. If you start a car in cold weather, it best to have them heat up completely in driving conditions. The exhaust system gets full of water too if you only do short “warm ups”.

 

Yes regarding oil molecules, though additives and impurities in engine oil have hygroscopic properties and the emulsified water in engine oil can be a problem as McSpazatron noted above.

 

WOW !!! I would like to thank ALL who responded to this Thread. Lots of interesting and informative replies.

My driving conditions are mostly suburban in a large city. Short runs with very occasional mild off-road (logging trails and the like). Vehicle just now ready to turn 25K miles. No towing. Again, probably 6-7K miles a year. Vehicle is garaged year round.

So, based on what I've read here, I should be OK with the engine oil and filter change every 5K. Which I just had done this past November 6. So I'm good till sometime towards the end of this year.
Transmission Fluid: Sounds like I should wait till 60K. Doing a full flush at 30K would probably not hurt anything if I'm the over-cautious type, which I'm not. But it sounds like it's more a waste of money (?) considering my mild driving conditions, most of which are back-to-back short runs. But I can't help thinking that by the time I reach 60K it will be 4-5 years from now. That's why I was thinking of doing the flush at 30K.

Fortunately, I seem to have a good dealership only 2 miles away. Never had an issue with them even back to my 2010 FJ Cruiser years. I will turn 75 this year. I will work on top of the vehicle, but I don't crawl under it anymore. (unless I have to). Can't really explain this. You just have to reach that age to understand. LOL But I figure with my annual mileage, this will be my last vehicle. So I want to keep it in good shape.

Thanks again for ALL the great replies.

 

That sounds like a good plan.

 

"That’s a big reason to never run the engine on stored cars, or rarely used cars, just to “circulate the oil” for a few minutes. Especially in colder weather. If you start a car in cold weather, it best to have them heat up completely in driving conditions. The exhaust system gets full of water too if you only do short “warm ups”.

That's interesting. My 4R sits in a garage that's at least 50F or above year round. What I've always done is that during the first cold-start of the day is to let the engine idle till the tach drops to 1,000RPM and the temperature gauge moves to it's first large digit. My thinking by then I know the top of the engine is getting proper lubrication. Is this not optimum ?

 

It's unnecessary.

The top of the engine is not all that critical as far as lubrication at startup.

The most critical parts are the main bearings followed by the rod bearings. As soon as you see oil pressure, these areas have been lubricated.

Another critical area is the piston skirts. When cold there is a little extra clearance to allow for expansion as they get hot from combustion. It is best to drive slowly and accelerate gradually for the first few minutes on a cold start. Letting the engine idle for extended periods only prolongs the warming up of the pistons.

 

A lot of going on in this thread.

I do the following.

First engine oil change at 500 miles
Second engine oil change at 1500 miles.
Third Oil change at 5 K miles, and from then on, every 5 K miles. Not on the dot, but still. I do it myself. I always use one quart of new oil to pour it down and let it out before I fill the engine up with the new one. Just my thing.

Transmission and Differential and other maintenance I just follow the manual. Easy.

I dont abuse my rig, just light off road trails, tow occasionally 3000 lbs trailer or 1000 lbs off road trailer. Camping and such.
I also recommend theCarCareNut channel on yt. Every advice I got from him, I did not go wrong.

 

You definitely win the award for most OCD oil changes. I’ve never heard of anyone douching their engine with new oil.

 

I never do any of that and don't like ccn dude either. 250k miles so far

 

I probably wasn’t clear when I mentioned the bit about warming it up a short time. I meant this in reference to cars in long term storage or cars that rarely get used. Some owners, with good intentions, might turn them on every once in a while, let it idle a few minutes, then shut it off. And they might repeat this occasionally thinking that it’s good to circulate the oil since they aren’t using the car. It’s not good because that just accumulates condensed water in the crankcase (and exhaust system).

If it’s a rarely used car, or a car in storage, it’s best to only turn it on if you can drive it 5-10 miles to make sure the condensation can boil off.