So... Toyota WS and Aisin WS are not the same.

J

Jonas

Joined
Jul 13, 2020
Messages
569
Hey all! I recently did three drain/fills on my 09 Vibe (Matrix) with Aisin WS. I figured, Aisin made the transmission, it's spec'd for WS fluid, can't go wrong. It seems to be shifting and working well as far as I can tell. (better than with the cloudy gray/purple mystery fluid that was in there) Just out of curiosity, I dug into the details of Aisin WS, Toyota WS, and a few alternatives just to see if one was maybe better than the others. Turns out Aisin WS and Toyota WS are very different! The most glaring difference is viscosity. Aisin: 34.88 cst @40C / 7.332 cst @100C Toyota: 23cst @40C / 5.45cst @100C. The ingredients are a little different as well, though I'm not entirely sure what they all are. The flash points are about the same (174/175) which seems kind of low to me? Couldn't find anything on viscosity index. Anyway, here are the MSDS for both fluids:
Toyota: https://cdn.website-editor.net/6622da50fd3744b3b1560a41005a6921/files/uploaded/00289-ATFWS.pdf

Aisin: https://attachments.priuschat.com/attachment-files/2020/02/182601_MSDS-English-AISIN-AFT-0WS.pdf

As I said, transmission seems to be working well, but I'd like any opinions, explanations, and/or advice from those of you who know what these sheets mean. Is the Aisin WS a good atf? It doesn't look very impressive to me, but it may be great. I don't know. Thanks in advance!
 
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Also, I frquently get vibration at idle mostly when stopped in drive with fluctuating rpm. Less with the AC off, hardly any in park or neutral. It did that before and after the fluid change, but still wondering if it might be transmission related. Thanks again!
 
It would not surprise me if Toyota's WS formulation was thinner for their CAFE goals, but you might also compare the cst of Maxlife ATF and see where that falls. I think you're fine to keep the Aisin stuff in there if the Maxlife ATF cst is close. Lots of members here only use the Maxlife and have reported great results.
 
Is the Aisin WS spec'd for your tranny? If so, then not to worry.
I haven't know of any spec'd ATFs that have blown up a tranny.
I also think your vibration is from a motor or tranny mount.
 
I can say that on the Toyota forums, members do use the Aisin fluid. I had a member suggest it to me because it was cheaper...I want to say it’s a few dollars cheaper per quart (and they supplied a coupon through the website).

I ended up just buying the WS fluid because it really wasn’t much of a savings to go with the Aisin fluid. And I have a Toyota dealer right down the street.

But I have read/heard in the past that the WS fluid is a very low viscosity fluid And nothing special/nothing to brag about. It’s supposedly not a synthetic fluid (not sure how that’s determined) and certainly not a long life or “lifetime” fluid. And one thing that is pretty common knowledge - the WS fluid does not hold its red color upon factory fill for very long. I’ve heard of people changing it at 20,000 miles and the fluid is already brown. I personally have owned 2 Lexus/Toyota’s with the WS fluid...one I did the initial change at 70,000 miles (fluid looked like motor oil...thought, oh my god! My tranny is junk, but it wasn’t) and the other at 50,000 miles (fluid looked even worse than the 70,000 mile one).

But strangely, after that first fluid exchange...the WS stays nice and red thereafter. Not sure why. Different fluid from the factory, in terms of dye? Clutch materials/break in material, gets the WS fluid darker than other fluids? Don’t know, but its the only tranny fluid I’ve ever seen that does that.
 
Jonas, I would appreciate your participation in this poll and thread on the exact same subject.

Poll: what'd you use in your WS-spec'd AT?

This poll had been posted in a less robust manner previously. Those answers are gone, so please vote again. Poll open for 90 days. If you do not meet criteria below, but are interested in results, you can see results without voting. Please answer the poll stating your preferred fluid for your...
www.bobistheoilguy.com
 
I use Maxlife in the transmissions. I try to change with drain and refill at 50,000 miles.

Your idle issues with the vibration sounds normal to me. You could try cleaning the fuel system gradually to improve that.
 
Char Baby said:
Is the Aisin WS spec'd for your tranny? If so, then not to worry.
I haven't know of any spec'd ATFs that have blown up a tranny.
I also think your vibration is from a motor or tranny mount.
Click to expand...
It is spec'd for WS and The Aisin is Type WS. I was just wondering why it's so different from Toyota WS.
 
Then you also have this: ($31.60 in a 5qt bottle $6.32/qt)

ATF Type TLS-LV | Idemitsu Lubricants

Engineered for and meets requirements of Toyota/Lexus/Scion Automatic Transmission with WS specifications.
www.idemitsulubricants.com www.idemitsulubricants.com


Appearance-VisualRed Clear Liquid
Density @ 15°Cg/cm3ASTM D40520.853
Kinematic Viscosity @ 40°CcStASTM D44522.8
Kinematic Viscosity @ 100°CcStASTM D4455.3
Viscosity Index-ASTM D2270175
Pour Point°CASTM D97-54
Brookfield Viscosity @ -40°CcPASTM D29836,900
Flash Point, COC°CASTM D92170
 
Do anyone knows of any fluid causes issue with the transmission, regardless of brand but meets the car manufacturer specification?
I agree you shouldn't put ATF for 4AT into CVT etc. But if a fluid says it can be used and meets spec for xxx vehicle and an owner uses it,anyone knows of instances where it causes issues?
What is difficult to ascertain is whether the transmission is already having issues and beyond repair regardless of what fluid you use.
Like I mention is some other post, fluid is no magic and transmission only knows the physical properties of the fluid.
If Aisin makes the OEM fluid for xxx manufacture, it cannot slap the Aisin label on the same bottle without being sued. It can easily alter the composition but still maintain the physical characteristic required and says it meets xxx spec.
So a VOA will see a different composition.
But Aisin(or other aftermarket manufacturer) may improve the fluid by making it last longer etc i.e exceed the spec, otherwise why would you buy non EM other than price?
 
reddevil said:
Do anyone knows of any fluid causes issue with the transmission, regardless of brand but meets the car manufacturer specification?
I agree you shouldn't put ATF for 4AT into CVT etc. But if a fluid says it can be used and meets spec for xxx vehicle and an owner uses it,anyone knows of instances where it causes issues?
What is difficult to ascertain is whether the transmission is already having issues and beyond repair regardless of what fluid you use.
Like I mention is some other post, fluid is no magic and transmission only knows the physical properties of the fluid.
If Aisin makes the OEM fluid for xxx manufacture, it cannot slap the Aisin label on the same bottle without being sued. It can easily alter the composition but still maintain the physical characteristic required and says it meets xxx spec.
So a VOA will see a different composition.
But Aisin(or other aftermarket manufacturer) may improve the fluid by making it last longer etc i.e exceed the spec, otherwise why would you buy non EM other than price?
Click to expand...


Welcome to the never-ending debate that several of us have about Honda DW1 and several of the aftermarket 'versions' of it. None of the aftermarket stuff looks anything like the original OEM DW1, but plenty of people use them with great results. You'll probably never find a definitive answer to your question unless you find the engineer at Toyota/Honda that designed the transmission and grill him/her about why the fluid looks like it does, and then consult with fluid engineers and find out what different mixtures can meet the requirements and why/how.
 
ctechbob said:
Welcome to the never-ending debate that several of us have about Honda DW1 and several of the aftermarket 'versions' of it. None of the aftermarket stuff looks anything like the original OEM DW1, but plenty of people use them with great results. You'll probably never find a definitive answer to your question unless you find the engineer at Toyota/Honda that designed the transmission and grill him/her about why the fluid looks like it does, and then consult with fluid engineers and find out what different mixtures can meet the requirements and why/how.
Click to expand...
Honda is probably that one fluid where I’ll only use genuine Honda automatic transmission fluid and nit mess around with anything else. Just from speaking from personal experience - tried the “universal” fluid with the “Honda additive” - didn’t work...shifts felt strange (some flares, some weird grabs from gear to gear). Changed out back out to genuine Honda fluid and went back to normal instantly. And their power steering fluid is “different” too (although I have used aftermarket specified for Honda and it was fine). But Honda just likes to make it difficult.
 
reddevil said:
Do anyone knows of any fluid causes issue with the transmission, regardless of brand but meets the car manufacturer specification?
I agree you shouldn't put ATF for 4AT into CVT etc. But if a fluid says it can be used and meets spec for xxx vehicle and an owner uses it,anyone knows of instances where it causes issues?
What is difficult to ascertain is whether the transmission is already having issues and beyond repair regardless of what fluid you use.
Like I mention is some other post, fluid is no magic and transmission only knows the physical properties of the fluid.
If Aisin makes the OEM fluid for xxx manufacture, it cannot slap the Aisin label on the same bottle without being sued. It can easily alter the composition but still maintain the physical characteristic required and says it meets xxx spec.
So a VOA will see a different composition.
But Aisin(or other aftermarket manufacturer) may improve the fluid by making it last longer etc i.e exceed the spec, otherwise why would you buy non EM other than price?
Click to expand...

I think that manufacturers really do a nice job of causing confusion and making you feel uncertain enough to only buy their fluid (when it comes to tranny fluid). For instance, DEX lV very well could be very similar to Toyota WS, but we don’t know that. ATF +4 could be similar to Merc V, but most of us just don’t know. Therefore we either buy genuine stuff or a multi vehicle Castrol or Valvoline.

I’ll tell you what though, I just use genuine with transmissions. It’s something I don’t change often enough to go around looking for alternatives. The price difference isn’t worth it and I have been “burned“ on two occasions going after alternatives...once in a Honda and once in a GM. With the GM I put a universal synthetic...can’t remember which brand it was but it was a green bottle. It was sold to our garage in bulk so we could use it in exchange machines. Well, I googled the fluid and wouldn’t you know...class action lawsuit against the fluid for not meeting DEX lV specs. Honestly, it didn’t feel different. But mentally it felt different - knowing the fluid didn’t meet spec - so I got it out of there and put genuine fluid back in.
 
The reviews of Castrol and Valvoline fluid in amazon has mainly being positive. The few that have issues, you wonder if the transmission already beyond rescue and owners uses the fluid as final attempt to resurrect the transmission. Like I mentioned previous post, there is nothing magical in a fluid used for machines unlike a pharmaceutical drug for humans.
Non OEM fluid must be better than OEM - technically and price wise, otherwise there will not be a market for it.
4AT transmission has been around a long time while CVT is new.
Idemitsu has fluid specific for each manufacturer while Maxlife is universal. If Idemtisu fluid better or just marketing?
 
Weber Auto on YouTube covers a pretty good census on transmission designs and you'll be amazed how many auto manufacturers use each other's parts. Take the 2016 Malibu with the 2L for an example, it uses the AF50-8 aka u880 used in the Camry which calls for DexWS or DEXRONVI. OR The Ford fusion hybrid/cmax that use the same power train as the gen2 Prius which calls for MERCON LV in Ford. I guess manufacturers are using the same formula, however spec'd to the OE. What are the changes do they make in the home brew? I've used AC Delco bottled DEXRON vi in a 2017 Toyota Rav equipped with the u760 with no issue.

Within a given statement, could it be Ford, GM, Toyota are just using their own given spec?

So looking at the product sheet of your multi vehicle ATF's. I believe they know more that meets the eye, Valvoline for a huge example: well known and trusted.



Being the backbone of actually taking apart these transmissions, I see exact designs internally and externally just different bellhousings.

In my actual findings...

Is Valvoline maxlife an exceptional product. I can simply vouch for this one, yes. It's a great product. I've noticed uniform shifting amongst almost anything I've put it in.

Amsoil fuel efficient SS? Yes, there's a caveat, I noticed transmissions upshifts a little harsh with it, even in the Hondas P79 when cold, this goes away when things warm up, some may find this annoying

Note amsoil OE fuel efficient formula runs a little thinner than it's signature series counterpart. Using my 14 Camaro as a test pig with the 6L50, harsh engagements when cold and you can hear it clunk.

In the past using Amsoil signature series ATF (red cap) in the 4r70w in manual down shift engagements, I've heard the torque converter chirp. Same results in the AOD.

Supertech dex/Merc low viscosity, 2015 Prius P410 seamlessly transitions from power mode to hybrid mode without the jolt. This product is also suitable in vehicles calling for WS.

Citgo multi vehicle synthetic ATF- Smooth transitions. No complaints here, just another run of the mill ATF

Pennzoil platinum ATF BULK, same as the Toyota WS, no change in data or shift patterns.

MAG1 low viscosity and traditional, same results of maxlife, it just works.

Having to maintain a fleet of vehicles, you can try different cocktails of brands.

Mag1 and maxlife offer great products that perform equally well. Everything else is just paying for more.

Castrol CVT/ATF, I'll report back once it has accumulated mileage. I currently run that in a 2016 Honda fit, 2020 Corolla and 2017 Elantra. So two CVT's and a step shift transmission.

My census, give the maxlife a try.

Toyota stock WS is garbage and I feel Mobil could've done more to make the fluid wholesome, I guess they were just the lowest bidder.
 
The site covers it pretty well in terms of evidence. It's not a full synthetic fluid, it's a run of the mill semi synthetic.. In the fleet vehicles I oversee, the WS fluid does not handle fleet usage very well. It comes out dark and oxidized. The black tarnish on filters and valve bodies. When I get back to the garage next week, I'll pull a sample from the next Camry I'm about to service.
 
toyotacarnage said:
The site covers it pretty well in terms of evidence. It's not a full synthetic fluid, it's a run of the mill semi synthetic.. In the fleet vehicles I oversee, the WS fluid does not handle fleet usage very well. It comes out dark and oxidized. The black tarnish on filters and valve bodies. When I get back to the garage next week, I'll pull a sample from the next Camry I'm about to service.
Click to expand...
Totally get that the fluid isn't top notch but just was curious if that's limiting the transmissions from living a long life (200k miles or more).
 
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