Toyota WS...my eyes hurt from reading

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PMK

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First official post here. Thanks to all for the valuable info.

Disregarding the "official" manufacturers must use the WS fluid statement, what is actually special about Toyota WS fluid?

I have read here it is synthetic.

I have read here it is not synthetic.

I have read it is inferior to Dexron VI.

Can not find out if it has a some form of friction additives.

Some have stated it is a simple low viscosity ATF.

Others have mentioned that other fluids are more than capable, but not submitted for the Toyota WS endorsement.


I have used Mobil 1 ATF in other applications before. It is not approved for WS applications. It is slightly more viscous. Does it have some type of additive that would benefit or harm the transmission?

The reason I ask, my 2010 Tacoma shifts very soft, but is deemed normal. Also, the torque converter at under 10 mph, gets confused. Sometimes you get a lot of slip and little movement, other times it drives like a normal automatic that will creep along when needed.

The dealer has seen the truck under warranty. The mapping and revision status of the transmissions electronic program are current. Basically explained this is normal and not broken.

So disregarding all the Toyota or Mobil approved / unapproved stuff.

How do these fluids compare?
Other than viscosity what is really the difference?

Thanks

PK
 
While I am as far from an expert as you can get, all of the research info I have been able to come up with says that Toyota WS is a low viscosity synthetic/semi-synthetic (depending on who you believe)fluid. Its initial intent was to reduce frictional losses in the transmission to improve gas mileage. Historically, Toyota large engine gas mileage has not been the greatest. I have a 1986 Olds Cutlass with a 307 V8 that get's better mileage than my 2009 Tacoma V6, but I bought my truck for a purpose.

Anyway, back on point, if you want to improve shift quality, try Redline D4. I did a complete flush following the procedures over at Tacoma World. The temperature check/fluid level part is a llittle tricky but practice it a couple of times before you actually do the flush. I also dropped the pan on the inital drain to clean it real good and so I could see what was going on inside. When I was doing my info gathering for this I called Dave at Redline to ask questions about D6 vs. D4 fluid. He told me the D4 fluid was more compatible with the OEM clutch material but that D6 was designed on a ultra low viscosity base...like WS fluid. D6 was also supposed to be shear stable at long change intervals. He recommended D4 for my Tacoma, which I have used for years in my wife's 2004 Honda Accord V6 and my Cutlass.

Long story short, I did the complete flush with D4 in my Tacoma a little over a year ago and I have been very happy. I had the Transmission ECU reflash done prior to correct the shift issue, there is a TSB for that. I am almost out of warranty so I don't care about the "only use WS fluid" warning. Redline makes top level products and have never let me down. I also use the 75W90 in the rear diff.
 
Short story short: it is thin, it will be significantly thinner than any universal ATF.

Weather or not this means universal ATF's will work is up for debate, and perhaps dependent on application.

One last note, the friction characteristics of M1 should be fine, it meets JASO 1a which is the criteria for WS (and most Japanese spec ATF's).
 
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Whether or not the base oil in an ATF is synthetic, blend, or conventional depends much on the transmission maker's choice for the length of life of the fluid. Viscosity at temperature extremes also is important. For example, GM's performance spec for Dex-VI does not specify the type of base oil, but only syn-blend or better can meet the performance requirement.

All ATFs contain some friction additives. These are designed to meet the friction requirements of the clutches inside the transmission. Each maker of transmissions has their own idea of the "best" friction conditions and has a fluid to suit. Some (Ford for example) have more than one.

Yes, part of the approval process is that the ATF maker has to submit and pay for their fluid to be tested. In most cases of the near-universal fluids, they are compromises that work very well but don't quite meet a spec so they'd never pass and get the license.

What to do for WS? Either use a licensed product, or a product "recommended" by the fluid maker (but not licensed by the transmission maker) for WS service. Or stick your neck out and use a fluid said to work well by other users.
 
Just wanted to share some of the info I noted while searching.

Toyota WS / JWS 3324 (manufactured by Exxon Mobil per the MSDS)
cst at 40 is unknown
cst at 100 is 7.2
VI is unknown

Ravenol WS / JWS 3324
29,9 cst
6.o5 cst
VI is unknown

Mobil Dexron VI
29.5 cst
5,83
145 VI

Mobil 3309 / JWS 3309 (should be Toyota IV)
35 cst
7.2 cst
180 VI

Motorcraft Mercon V
33,2 cst
7.5 cst
205 VI

Mobil 1 ATF
36.3 cst
7.4 cst
VI 176

General internet Toyota WS discussions mention, but do not back up with data
25 cst
6.0
Unknown VI

If my notes are correct, the Toyota WS, Toyota IV, have identical hot cst of 7,2.

Compared to Mobil 1 ATF, Toyota is 7.2 cst vs the M1 at 7.4 cst.

Any additional input or thoughts?

Thanks
PK
 
http://www.mitasuoil.com/en/atf-ws
Attached is link for miatasu oil,I have researched this Toyota WS oil, which I purchased from Toyota Australia.
What is reconizable is the tin this company sells the product in, it is identicle with the Toyota tin, same lid etc.
I believe this company makes the product for Toyota Japan.
It is very thin in viscosity, have contacted Fuchs Australia and they stand by their Titan ATF 4400 as a replacement, also Penrite ATF FM5 is recommended to do the same task.
You should not have a problem with the Mobil product speced WS.
Hope this helps.

Regards
Jeff White
 
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