After reading all 23 pages (so far) of this thread, what I gather is it is okay to do this as long as you do not have pre-existing conditions.

As an added precaution I did a transmission service this past weekend to check the state of the fluid, the level of varnish as well as any metal bits caught by the “filter” which as others have stated is a fine metal screen as opposed to any sort of filter media.

My 4Runner was new to me last year with 200,000 miles on the clock and zero service history. I now have 225,000 miles with no issues from the transmission. I was pleased what I found while doing the transmission service. When I drained the fluid, it was dark red with some transparency, so I assumed someone had been in there before. Dropped the pan and found no surprises in the bottom. Checked the filter over before replacing it and only found very fine or small pieces that were no cause for concern. Then I proceeded to fight ONE broken bolt that I broke while taking the pan down. That’s beside the point. Lastly I filled the transmission with 4.5 quarts of OEM WS fluid before doing the trans temp level check.

The point of this post sharing my experience is like others have said, it is okay to do this fluid exchange if you know the state of your transmission. I would not advise “YOLO” and just go for it as your transmission is not cheap to purchase or have installed. If you are interested in this I would advise you do what you can to “gauge” the state of your transmission. If you know your 4Runner was neglected (like mine was) by its previous owner/s then do a drain and fill first to see how the fluid is. Replacing that small amount of ATF will not get you in trouble. If that goes well, drop the pan to inspect the fluid, inspect the pan and filter. Can’t hurt to clean the magnets and change the measly “filter”. That also should not be too much fluid changed to get you in trouble. If the previous two go well, lastly go ahead and do the fluid exchange. These may seem like wasted time and money but the little you will pay for fluid and a gasket is FAR less then replacing a transmission and having it installed if you’re not capable of it yourself.
To be clear I am not saying my way is best but it has really helped put my mind at ease.

I will be doing this fluid exchange in the near future with Valvoline Maxlife and adding a Magnefine filter now that I have put my mind at ease knowing the state of my transmission and it’s fluid. Thank you to the OP for the write up and thank you to all the other posts. This forum has given me the confidence, knowledge and ideas to try these things myself. Hoping my 4Runner goes much further.

P.S. I wrote this for the high mileage guys like myself who purchased something they have no history for or have not owned it with low mileage and were responsible vehicle owners changing their fluids.

i just took mines in to the dealer for the atf fluid exchange service, 385.61 , seems like they used the cooler lines. i have no bad transmission symptoms. first change was at 100k, then 158k . now im at 202k.

Really nice and informative write up. I am brave enough to change other fluids but after I had trouble with my then Kia mini van after ATF was done by jiffylube, I will have to swallow the price and have my toyota dealer do the ATF change on my beloved Runner...

very easy to do an ATF exchange yourself if you follow some of the pointers myself & others mention in this thread... or just watch some youtube videos on doing this. takes all of an hour or so & the fluid level check is straightforward. nothing wrong with paying to have it done but definitely doesnt need to be at the dealership who will charge more than any other reputable shop. & i would never let a jiffy lube change ATF let alone oil.

It's been a while since I changed mine, I forgot to say I didn't use Toyota WS.

Sorry any total diehard Toyota fans, I don't believe it's the golden elixir. I've been choosing my own non-OEM fluids on motorbikes and cars for over a decade and never had a single mechanical failure.

(Oh - one exception - my CR-V which needed genuine Honda fluid in the rear diff. I bought genuine Honda DPS-F fluid for that.) As you can tell I don't choose fluids without doing research, and I was happy to use this ATF.

Motul Multi ATF Fully Synthetic Automatic Transmission & Power Steering Fluid


I don't know if it's available in the USA, but it might reassure someone who is worried they didn't use Toyota WS.

All has been well. It meets every Toyota standard. Toyota ATF D-III, ATF WS, ATF Type T, Type T-II, Type T-III, Type T-IV, JWS 2312D, JWS 3309, JWS 3324, LF, # 08886-81015, # 08886-00405

Changing your motor oil with the engine warmed up is beneficial in draining as much oil as possible, so I usually change mine right after returning home while the engine is hot. Does the same apply to the ATF exchange process?

changing the oil warm is the best way, mainly because it has all the debris mixed up in the oil vs settled on the bottom of the pan if it sits too long. being 5/30 is pretty thin i think 99% of it will drain out whether warm or cold, but i agree warm is best.

for the trans fluid, since its not thick like oil i dont think warm or cold makes much difference. & since an exchange is pumping it out the debris are mixed up after the first one or 2 start ups but doing it warm wont hurt anything. the only thing to consider is that you are putting back in cold fluid so probably dont want the trans/ATF at full hot temps.

Successfully completed this fluid exchange this past weekend. I used about 12 quarts to complete the exchange. I did the process by using the trans cooler lines that come up to the radiator and filling through the fill port on the trans. The process was very easy once everything was set up to collect and fill fluid.

I used Valvoline ATF. There was a noticeable difference on the first drive after completion. I recently did a pan drop/filter change and filled with OEM Toyota WS fluid, after that service I had a noticeable increase in “judder” at low RPM and light throttle. After this service exchanging for Valvoline synthetic ATF that “judder” is completely gone. After all that was done I installed a Magnefine filter to help filter the fluid since the “filter” in the pan isn’t much of a filter. I have my Scangauge hooked up to monitor temperatures going forward.

Thank you to all who have posted. Here’s another 4Runner saved and improved. I completed this with 226,000 on the clock.

Attached Images

   

& another successful maxlife ATF change... improved shifting right away & actually improved or stopped your shudder issue too!

so much for the maxlife & other brand ATF naysayers or those that think a full exchange at 100-200k miles will cause damage.

Sometimes OEM is best, sometimes aftermarket is best. In this circumstance I believe the aftermarket fluids are better.

I can’t blame others for choosing to use OEM fluid, especially with one of the largest components on their vehicle which can be very costly to repair, replace or worse replacing the vehicle. But I also question why someone would not use Aisin WS fluid since they are the manufacturer of 4Runner transmissions and a lot of other transmissions. (Yes I am aware Toyota is part of Aisin). Is there a difference between Aisin WS and Toyota WS? Why did the formulation of Toyota WS change when they changed manufactures for the WS fluid? Was it a cost saving measure for them or a better product for them? There are many more questions to be had and probably very few answers.

Doing your research, to me is key and that is what lead me to doing this fluid exchange. Being informed on what your options are and what others experiences have been will lead to trying it or staying away from it. If I would have listened to my father, “if it’s not acting up I would leave it alone” then who knows where that would have lead. Doing my own research allowed me to be comfortable to do this. Some people just have the mindset that deviating from factory fluid will lead to failure, maybe that’s what they learned from someone else. Also taking the word from engineers as gospel is maybe not the best mindset. I wonder what their answer would be if they were not answering in a “official” manner on behalf of the OEM. They have to keep continuity on behalf of the OEM. The thing to keep in mind is they are probably car people as well and know there is not a one fluid for all or that there is nothing better.

The last thing that put me over the edge about using Valvoline was seeing how they stress test components to the point of failure to see how their product holds up. I know they do this with engines, I’m not sure if they do this with transmission fluid but I choose to believe they have.

This reply has officially turned into a rant. I think I should go ahead and wrap it up here. Haha

I choose Toyota WS because:
- the idea of one aftermarket fluid meeting so many different manufacturers’ standards makes no sense to me;

- I’m into evidence and nobody I’m aware of has anything past anecdotal data; and

- as I understand it, Valvoline makes no warranty, express or implied, if anything goes south.

I know for certain that WS works.

In any case, I wish everyone the best outcome regardless of what they use. It’s not my place to say one is better or try to convince anyone to use this or that. It’s your truck and if you trust Maxlife, by all means use it and may all your shifts be smooth ones.

my take on the "universal" ATF's is that they are fully tested to meet the specs of other fluids, no company would make & sell a product that would harm a trans or engine etc, & if they did they would be off the market real quick with class action lawsuits to follow... after almost 2 decades of maxlife & other brands like amsoil & motul etc etc being used with excellent results its pretty safe to say & far beyond anecdotal evidence that they are safe to use & high quality full synthetic fluids.

science & engineers develop new fluids & products that are as good or better than factory as time goes on. think about dex/merc ATF, it has advanced & been improved many times & each new version meets the specs of the prior, dex2, 3, 4 etc. the whole "logic" of how can an aftermarket fluid meet the specs of so many manufacturers is pretty simple, they have designed it from the ground up to meet numerous specs, ATF isnt rocket science, its a hydraulic fluid that needs to be in the proper viscosity range with some additives for anti shudder & cleaning agents, the fact one fluid can meet different manufacturer specs makes perfect sense to me, they dont meet all, but the ones they are tested to meet are perfectly safe to use & millions of customers prove that. to think a huge company like valvoline (ashland) or amsoil cant design a simple ATF to meet WS & other secs in modern times is what makes no sense to me.

nothing wrong with using WS, it obviously was designed for these transmissions, but there can be & are better fluids 20 some years later, just like oil is far better than it was 20 years ago. & the fact these newer synthetic fluids are cheaper & probably stand up to heat & abuse better & many times are reported to improve or fix common issues like trans shudder.

Motul is top quality, I use their oils in specific applications due to the cost. 300V engine oil in an old BMW 24v I6 and I mix their ATF and MTF for the Getrag 280 gearbox on the same car. It has phosphor-bronze synchromesh rings that are very finnicky and the Motul mix has stood the test of time. Might give the ATF a shot in the 4 runner, why not.

A 20 litre barrel (5.28 US Gal) is over £220 now! (I paid just under £200 in April, that's a 9% increase) I have enough left for a standard oil pan drain and refill, I think I might buy another one and a load more spares with this inflation.

To those people putting magnefine filters, I have a question, my Runner is just 15,000miles and will not be doing any drain and fill yet but I want to put a filter.
Since the filter is empty, do I need to fill it with a little fluid as it adds space and will take up some of the fluid already circulating in the system?

I just watched The Care care Nut channel (Toyota tech) on youtube and someone asked him if he would put a magnefile filter and he answered not necessary.

Toyota Trucks Sealed Transmission Fluid Replacement WITHOUT a scan tool - YouTube