Suitable substitutes for the Toyota ATF-WS transmission or transaxle fluid?

I was going to post that photo today! You beat me to it!


QUOTE="Peter123, post: 3019320, member: 169479"]
Toyota WS is cheap enough and easy enough to change that I just do that.
The problem is that I need to get a round tuit.[/QUOTE]

 

John Kelly is the Prius guru. I wonder how he feels about LV fluid in the eCVT?

 

From Toyota. Enclosed is a photo of the parts...
The only thing I found cheaper was the intake manifold gasket. I got it for about 1/2 the cost...
Everything else was only a few cents less. And I think the coolant was a dollar or so less. So it
just wasn't worth it to get it for that. The parts guys have been very good to me, so I will continue to
buy from them!

I asked if they give a veterans discount and he said sure....
If you are a veteran, you should ask. Most places do give a 10% discount. It ads up!

 

I believe 3rd gen Prius and 4th gen Prius used transmission fluid to cool the coils winding in addition to water cooled jacket on the outside. Prius C or Yaris Hybrid only used the transmission fluid to cool it but with 2-3x more flux of ATF. For the past 10 years, we almost get 0 reports of failing 3rd Gen Prius transmission. 2nd Gen have some problems either on the needle bearings and chain and burned coils. My hypothesis, AISIN figured out how to cool the whole electric and mechanical system by bathing them all with ATF which is highly dielectric. TSB stated about possibility of WS ATF adsorbing water may be related to this, just like brake system more conductive when water is adsorbed.
I believe in open market, and against any monopoly. Valvoline, Mobil1, Ravenol, Aisin, Motul made compatible WS ATF, and it is proven to be fine as long as it is high quality stock base with good additives. From price point of view, Valvoline is the cheapest and proven to be good. Ravenol WS is cheaper in Europe and european use them in Aisin Transmission (Peugeot, BMW, Volvos, Mini, Opel, etc.). Toyota dealer in Europe is charging extremely high for any fluid. Oil change for Prius is 186 euros or almost $200. It is 2x than most USA dealers charge for simple 0W-20 Exxon/Mobil1/ToyotaOEM.

 

The difference in the price is cents, perhaps 1 or 2 dollars. That is what I found as I searched
for something that cost less and that "should" work. It makes NO sense at all to put something
other than what is supposed to be use. For me, it's not worth the risk to save $2.
But people can do whatever they want with there own property.

 

Well, Valvoline warrants your tranny if you have their shops do the change first at 50k mi, then every 30k mi thereafter. To me that's insurance, that Toyota will not provide with WS.

moto g(7) power ?

 

@johnHRP:

Here I got Toyota ATF WS for $9.14 (CDN) per litre. But I've read in European countries it's very expensive.

Also, what you say about it absorbing water: Toyota says in one document to only use fluid from freshly opened bottles, seems to corroborate that.

@jzchen:

Just judging from drained fluid colour, I'd be inclined to do first drain early, then stretch it.

 

That's what a they tried to sell my on my first trai fluid change..... the parts counter guy said my trani would blow up in less than a mile if I didn't use the stuff in the can. Went to the other Toyota dealer.....

 

Valvoline warrantying the trans should be a red flag.
Oil and water don't mix. So, if WS does absorb water, it would evaporate from how hot it
gets while driving. Another reason there is an expansion valve on top of the trans.
If you read the owners manual, and all other manuals that came with the car, it will tell you
what fluids to use.

But again, do whatever you want with your stuff.

 

Here's some info from Toyota, regarding water absorption, recommendation to use only freshly opened bottles. Excerpt:



And full document attached:

 

BOTTLES! NOT the fluid IN the transmission.....
Since I'm certain (and probably Toyota also) the transmission gets above 212 degrees (water boiling point)
ANY moisture that MAY get absorbed inside the transmission, will be more than likely get burned off.

 

The recommend it because WS has a big calcium pack in it to mitigate acid which keeps the tan low.

 

He stated that the G2 was bathed in fluid. I talked to him about that and he admitted his mistake on the G2 the fluid does not contact the winding's on a G2 but on a G3 and beyond trans fluid is circulated across the winding's to help cool them. Makes sense that could help cool them. G3 motors are much higher horsepower=more current thru the windings and probably get much hotter than the G2 motor windings. And they improved the Inverter coolant system on a G3 to help deal with that trans heat no more sharing a rad with the ice coolant it has its own rad.

 

Hi sorry to bump an old thread, but I had some info to ad and wanted to thank ed for making me aware that mg2 in gen2 prius does not bath in atf..

I have a mate that looks after a fleet of hybrid vehicles in our local area and quite a few of them are running non genuine full synthetic "ws compatible" atf, he has encountered a couple transmission failures in camrys and autopsy revealed the lacquer on mg2 windings had broken down and failed, these mg2's looked quite tanned or stained when compared to mg2's from vehicles running genuine WS. Yuck!

So then! If mg2 in prius gen2 does not actually make contact with atf at any stage I see no reason not to replace the atf with a good full synthetic WS compatible substitute, and I will be doing my partners gen2 next week now that I have been made aware of this, thanks ed.

Personally I will only use WS in camry, gen3 or any other Toyota hybrid where mg2 drowns in atf as the ws "apparently" has additives that help stop the lacquer breaking down, which is something that I am scared of, trust me I would love to get away from WS but I really don't enjoy changing out hybrid transmissions.

Thanks again, cheers

Matt

 

Normally I'm VERY skeptical of the theory that you "have" to use OEM fluids in cars, but the fact that Prius transaxles (power splitters) have motor generator windings in them have kept me from recommending ANY non-oem fluids for this unit.

You're literally better off NOT changing the fluid than you are experimenting with "something better" or "cheaper".

As always.....

REAL WORLD mileage....WILL vary.

 

Hi yes agree 100% when it comes to gen3, but if gen2 windings are not bathing in atf that's a completely different story

Posted via the PriusChat mobile app.

 

???

Didn't know that.
Learn something new every day.....

 

Its not laquer its a super hard conformal coating. The oil is not breaking it down heat is that's why the winding's are discolored they have been over heated from high current going though them high load & low battery voltage.

Want to destroy a electric motor stall it high speed with low power.

Perfect storm for a g2 is high load (your foot on the gas pedal demanding speed it cant produce) ) and low hybrid battery charge.
The trans windings are the weakest link current wise. They over heat and blow out. has nothing to do with external forces.

Many a G2 driver has been left on the side of the road with overheated trans & inverter trying to climb a big mountain with A full car and low battery voltage. Its the G2's trans Achilles heal.

They fixed that in the G3 much higher powered motors the windings are exposed to the fluid much better cooling of the trans and inverter with separate inverter fluid cooling chamber from the ice coolant.

But back to your post the g2 does not care what it uses for trans fluid. Its all a question of what quality GL4 lubrication you demand. I have used Redline D6 in my G2 trans for 12 years.

Best GL4 on the market.

 

Very interesting!

Only thing to add here, the gen3 actually got smaller less powerful electric motors than the gen2. Also a more compact design, and eliminated the chain. Gen3 made better use of its smaller electric motors with changing the ratios/final drive.

 

No that's not true. They have much more powerful mg's. The G3 is a much more powerful car. It also does not suffer from winding blow out like a G2 but it sure has its share of other issues.

Why would they have less powerful motors?