IS250blue

Hello folks,

I know this is not new topic about IS 250 sealed transmission. But, I just have an idea how to flush and refill transmission fluid without complicated OBD II reader calibration. Plus, the Toyota WS fluid price drops dramatically to ~$10/ quart, which makes it imperative to maintain your transmission. I hope to receive comments from ones that might have done this before.
I'm planning to
1/ Keep the car completely cool to avoid any error measurement due to heat expansion of the fluid.
2/Drain and contain the transmission into glass graduate/ container.
3/ Mark the level of the drained fluid in the container
4/ Dump the oil fluid.
5/ Put in the new Toyota WS transmission fluid up to the same marked level.
6/ Pump this entire volume back to the transmission+ extra a tiny bit accounted for the fluid left on the graduate/ pump equipment.
I also posted the instruction from factory service manual for guys interested to perform this DIY
Hope to receive your comments

Kurtz

iTrader: (1)

Your directions do not tell you how to drain the transmission. Because doing so is not physically possibly DIY.

It tells you how to re-fill it if it has lost any amount of fluid.


Your owners manual explicitly states, in muliple places, that it is never called for to change the fluid, and that it is a lifetime fluid.

Even dropping the transmission pan entirely will only remove 10-15% of the fluid in the system.


This has been gone over repeatedly.


The only way to change a significant amount of fluid (and again, the manual explicitly tells you not to) is using not only a specialized, expensive, machine for it, but then an additional specialized adapter that's relatively new.

Not something one does themselves in their driveway.

So step 2 is a non-starter already. Apart from the whole it being explicitly contrary to the recommendations in the owners manual.

My0gr81

Here is the full capacity for the Transmission fluid. A drain / fill cycle can be done by removing the pan and topping what was removed. Doing this until at least 80% of the capacity has been replaced. It is tedius and expensive even as a DIY. Lifetime fluid, means lifetime of the transmission, granted, this may be a lot longer than what most intend to keep the car, but realize that some people buy cars for the long haul, and for those, fluid change started early, and often is the best bet.

Caution: If you already have high mileage on your existing transmission without having done any fluid change, you will be bettter off leaving well enough alone. New fluid would probably cause more problem as it's new found detergen capability may dislodge contaminants into the system.

Automatic Transmission
*: The fluid capacity is provided as a reference. If replacement is necessary, contact
your Lexus dealer.
Fluid capacity*
IS350 (2WD): 8.3 qt. (7.9 L, 6.9 Imp. qt.)
IS350 (AWD): 10.5 qt. (10.0 L, 8.8 Imp. qt.)
IS250 (2WD): 7.9 qt. (7.5 L, 6.5 Imp. qt.)
IS250 (AWD): 9.9 qt. (9.4 L, 8.2 Imp. qt.)
Fluid type Toyota Genuine ATF WS

Kurtz

iTrader: (1)

Removing the pan will get about 1-1.3 out of that 8-10 removed.


It'd be kind of insane to keep swapping 10-12% of the fluid in hopes that you eventually change "most" of it...maybe.. and hope you don't introduce any outside contamination to the fluid yourself any of the the many many times you'll be dropping the pan off and on.


If for some bizarre reason you're confident you know more than the engineers who designed and built the vehicle (who say you never need to change the fluid) then find a shop with the proper equipment to do a full fluid change- and again that requires more than just a standard fluid exchange machine as there's no external connection from the factory to hook one up to.

(and insure that's what they're actually capable of and actually doing- as many shops will dishonestly just drain the 1 liter out and replace it and then bill you for a "transmission fluid change")

KillaIS250

iTrader: (1)

Like Kurtz explained, there really is no reason to change the automatic transmission fluid. There is a member here past 250k miles now on a 2006 without ever having changed the transmission fluid. There has been only one transmission i've seen on CL that needed replacement - and even then that member said it was because of damage to the transmission caused from driving in snow.

IS250blue

Hi guys,
thanks for your comment. But as you know engineers often do not have a strong voice in designing a product that will not profit their company. For instance, if anyone of us has own a BMW or a Mercedes all known their immature breakdown of transmission around 80K. I personally owned an BMW z3 that claimed lifetime transmission, and suffered cranking noise at 83K. I found out that even though on paper it said so, but all bmw technician preferred to change it around 50k or even more often if you intended to keep the vehicle longer.
And the matter of fact is cost of 1 quart of Toyota WS standard oil is just $3 more than a type IV, tells you that it's arguably any special than a conventional toyota type IV fluid. On top of that, if you look into the transmission filter part, it share the same part as the rav/ camry, both of which have 10-15k recommended transmission fluid change.
In conclusion, I think that Lexus has done their cost analysis and purposely implemented "lifetime" transmission fluid as the way to shorten ownership life of their vehicles

KillaIS250

iTrader: (1)

I was gonna reply to this post, but i'll just let Kurtz do it because something tells me his reply will be better

IS250blue

LOL,
anticipating great reply. But, let's mathematically lay it out. Assume that your mixing the oil and new fluid well, it takes around 4.3 times to replace 50% of the fluid. My assumption based on 1 liter drain out/ time compared to 7.2 liter total volume. Cost 10*4.3=$43+ maybe 4~5 hrs because you need to run for a short distance to well mix the fluid before you drain it out again.
LOL, it's fun and nerdy to think about it.

Kurtz

iTrader: (1)

Your assumptions have some flaws...

First you assume you actually need to change it...

We've not only got the guy with 250k, but a LOT of members over 100k. 0 failed automatic transmission due to not changing the fluid.

BMWs and Mercedes break down a lot more often because they're both significantly less reliable brands than Lexus. I mean, the BMW 335i has very very very high numbers of high pressure fuel pump failures.... the 2IS doesn't though.

I'm not sure where you got that the Camry requires fluid changes every 10-15k miles either-
http://www.toyota.com/t3Portal/docum..._Camry_WMG.pdf

It never, ever calls for changing the transmission fluid. It does recommend to check it every 30k, but that's it.

(though I'm not sure how even that is relevant given it's a completely different transmission that doesn't even drive the same pair of wheels)

Oh, and here's the Rav4-
http://www.toyota.com/t3Portal/docum...a_RAV4_WMG.pdf

Guess what?
For the 2WD/normal use (which again drives the wrong 2 wheels compared to the 2IS) you check it every 30k, and never, ever, replace it.
The only "replace" interval they give, ever, is if you tow with the vehicle. Then it's every 60k not every 10-15k... and the 2IS doesn't tow.

But again neither is the same transmission as the 2IS has anyway..



But then your assumptions about how to replace 50% of the old fluid have flaws as well- your method isn't doing that.

It's replacing 50% of the total fluid. Some of which will be new fluid (more and more each time)

Let's do some simplified math here:

Let's say there's 10L total (for easy math, plus that's close for the larger volume ones).

So you drain 1L of old fluid and add 1L of new.

Now you have 9L old and 1L new. 90% old now. Great.

Now you drive it around and (though this isn't necessarily true) we assume you totally mix the fluid up perfectly. So any given amount taken out now is 90% old fluid and 10% new fluid.

So you drain 1L. 0.9L was old, 0.1L was new. Now you fill with 1L new.

Now you have 8.1L old and 1.9L new. Now do it again- only 81% of what comes out is old, 19% is new.

Now you have 7.29L old and 2.71 new. Now do it again- only 72.9% is old... and so on to:

6.56 old and 3.44 new...then 5.9 old and 4.1 new..then 5.31 old and 4.69 new... now on change number seven you finally get to:

4.78 old and 5.22 new.

Congrats, after 7 fluid changes you've managed to change just over half the fluid.

So $70 in new fluid, and probably closer to 10 hours in your own labor (and I assume your time is worth something, yes?)... I mean the average american makes somewhere north of $20/hr, and I'd imagine the average 2IS owner is a decent bit higher, but let's just go with $20...you've invested $200 of your time plus the $70 in fluids.... so $270 to change half the fluid.

And let's hope none of the 7 times you have to open up the transmission to do that you get any dirt or contaminants or anything else in there.



Or you can just pay a shop with a real fluid exchange machine and the Lexus transmission puck adapter required, to do a full exchange of fluid for probably less than investing a ton of time to hopefully change half of it will cost.

IS250blue

thank for your reply,
First, let's talk about the transmission fluid. I personally had 2 friends, one owned 2007 Sienna got 60K before he had to repair his transmission due to overdue transmission. Another friend, got severe transmission problem with his camry 09 around 70k. that is the fact that every single experienced mechanic recommend you to change your trans fluid every year/ 15k if you really want your car run smooth. Unless you are careless about what you own, and put out cash every 3 or 4 year for a new one, than you are a lucky one.
let's talk about incentives. Money rules 101, will the dealer recommend you something that will hurt their sales? Don't forget why car company used to make much more durable cars back in 80s or 90s, especially japanese makers. So, overlong run their sale will go down if the cars keep running.
One problem with dealer service is they put down whatever they want on paper. For examples, my friend, currently working as mechanic for Toyota dealer in california, said for >$150 you will have a comprehensive inspection. Let's face the fact that he even admits to just eyeballing the car. And, if there is any problem, it's almost impossible to figure it out. Unless your car falls apart.
About the math, let make it more convenient to calculate. Assume n is the required number of time to change the fluid, every time we drain out 1.0 liter/ 7.2 total, which accounts for 13.9%. So, the fluid remaining is 86%.

let the remaining fluid is equal 50% and figure out the number of change. And, assuming they mixed well.
0.86^n= 0.5
n=ln0.5/ln0.86=4.59 times
I dont know how you got seven time???
Thank for viewing

My0gr81

Previous e46 owner with the ZF built "lifetime" transmission. The exact same transmission was on the e36, yet it had a recommended change interval of 60k km/ 40k miles. BMW went with all service included pricing, and lo and behold, the transmission fluid is now lifetime. Engineer build components to last as long as possible, it is conceivable that they designed and built the tranny to operate w/o service for well over 100k miles, It is the marketing and the actuarials in finance that make the cost/benefit analysis of what is it worth to introduce a $500 service item at 100k miles or call it a day and only deal with the low rate of breakdown while on warranty and let each owner deal with the low rate of breakdown after 100k. From a marketting perspective, it doesn't matter that the tranny could have lasted longer than 100k miles with a fluid change, the fact that it did without one is already more than what most people expect anyway. Those are called trade offs that engineers make to marketing everyday. AMHIK

IS250blue

I think My0gr81 is perfectly correct. It's the matter of how you deal with your car after 100k. Since, the company have been careless after your warranty expired at 60K. The important point is whether the company wants to let the user maintain their car longer or not. Remember that back in the days 1997, when BMW and Mercedes chose to eliminate the options to maintain their transmission. Their car owners almost had to face with transmission breakdown at 100k. Several of my coworker had the same outcome like my BMW Z3.
Talk about chemistry and physic, regardless of whatever you put in, the fluid integrity is greatly dependent on the driving condition. If you drive like a grandma, of course your fluid last longer. But, if you live in california or Texas and facing with traffic constantly, the breakdown is way faster than it's supposed to be. And, let's me remind you that German engineer had shown the proof of those mechanics breakdown in the last 15 years.
Furthermore, if you ever look at the filter mechanism of Toyota cars, they only emplace magnet+ microfiber filter. If you ever changed one, you know how bad it turns out after 15k interval. I personally experimented 45k transmission drop pan change+ filter. The magnets were gunked up with metal particle.
Let's make it short, if you don't want to keep your car long, who care about transmission. But, if you are the one treats your car as a good friend, you will dedicate more to it.

Kurtz

iTrader: (1)

And for every friend you have with terrible problems I've got 2 who went 200-300k without them in even more cars that don't have the same transmission as the 2IS does.

"I've got a couple friends who...." isn't evidence of anything useful... even less so when you're discussing completely different vehicles.

Though it is kind of telling that even among the thousands of users on here we have zero with a transmission failure due to not changing the fluid, even with many well over 100k.

I mean, law of averages, there should be SOME failures if changing your fluid is so important, right? Even a few, right?

Yet there's none.




The only mechanics I know (and I know quite a few, have had 2 different family members who owned shops, my best friend does nothing but Toyota/Lexus work out of his own shop for a living, and I've done a decent bit of my own work over the years) who say to change transmission fluid every 15k are the ones who would really like to bill you that often to do it or are towing constantly.

I mean, do you also fall for their line when they tell you to change your engine oil every 3000 miles too?


I can't think of any car made in the last 20 years or more that recommends doing it that often apart from maybe very heavy towing use.... every 30k is about the most often you saw...(and heck on the Rav4 you wanted to use as an example it's every 60k WITH heavy towing)

You're simply making stuff up now man.... just like you made up the "recommended" 15k changes for the Camry and Rav4 that I disproved direct from the manuals.

I've owned a fair number of cars in my life... I think I've sold one, ever, with under 100,000 miles on it....a few with closer to 300k... and all still running great when I sold em...

0 got annual tranny fluid changes though. (most certainly got the fluid changed, but roughly as often at the scheduled service suggested, which is far less often than you suggest)



I laid the math out pretty clearly. Each time you change that 1L, less and less of it is old fluid coming out.

Perhaps I need to show it to you yet again...let's use real numbers with an IS350 RWD.


Start: 7.9L of old fluid.

You drain 1L and put 1L of new fluid in.

You now have 6.9L of old fluid and 1L of new.

Now you drain 1L out... but only about 87% of the drained fluid is old... so you only removed 0.87L of old and the rest was new. You add 1L of new.

Now you have 6.03L old fluid and 1.87 of new. Do it again. But now only 76% is old. So you only removed .76L old- you now have 5.27 old and 2.63 new.

And so on giving you:
4.6 Old and 3.3 new
then
4.02 old and 3.88 new

This is after 5 changes and you're ALMOST at 50%... and that's the RWD model.

Since the AWD models hold a fair bit more fluid they'll be closer to the 7 changes needed in my 10L example, but let's call it 6 to be generous.


So you're doing 5-6 changes to get nearly 50% of the dirty fluid out. $50-60 in fluid, but 6-8 hours of your time (giving time to mix the fluids- plus time to go dispose of the used stuff, etc).... plus risking getting contamination in the system 5-6 times as you keep opening it up and refilling it.


Or you can let a shop change 100% of it with their machine for a similar cost.

Now run that diminishing returns math to see how much more your plan costs to get anywhere close to 100% fluid replacement... even 90% worth. It's a lot more than the shop doing it 100% once.

On what planet does your plan make any sense?

KillaIS250

iTrader: (1)

Bottom line: If you think its worth all that hassle, it's your car, go for it.
There are thousands of other 2IS's out there that will run perfectly fine beyond 100k without any transmission fluid service.
With some members around 150k and one above 250k without transmission issues, I don't believe it needs changing.

Crispy

iTrader: (3)

This discussion brings back memories of debating this on the e32 forums...

I have owned one e32 and one e34 BMW, both with identical ZF 4HP22 EH transmissions, both with claimed lifetime fluid. For reference, the e32/e34 Bimmers were made from roughly '88-'94, so the vast remaining examples are high-mileage. Understandably then, this was of much debate with owners as the transmissions began to fail. From my personal experience, I donated a '91 e34 with 153K miles that had just begun to experience the tranny shudder signaling the beginning of the end. The '89 e32 needed the tranny replaced at 168K miles. This was fairly consistent among owners.

Now, as more and more failures started happening before the vehicles themselves had reached end of life, the lifetime fluid was brought into question. Long story short, ZF claimed their statement of lifetime fluid referred to the life of the transmission, not the vehicle itself. BMW continued with this statement, as well.

This may seem counter-intuitive, as one may argue regular fluid changes may have extended the life of the transmission, but owners were advised not to do this. ZF/BMW responded that by the time the fluid would theoretically need changing, the process of flushing with new fluid, combined with newer detergents, would lead to failure anyway. This is what led to their claim of lifetime fluid.