New CVT oil ??

Amsoil TS wrote:

"We have tested for all the specifications on the data sheet. We meet, and exceed, the specifications. We do field testing on every product, but expecting every condition (weather, elevation, driving style, other driveline wear, modifications, etc) is just not possible. We focus on meeting and or exceeding the specifications themselves. If it does not meet or exceed a specification, we will not list that specification for the product."
Does Amsoil get a better datasheet?

This is all I can find for Idemitsu CVTF type SB2, and the only spec they say it meets is the CVTF-2, no others.

Characteristics Units Test Method Typical Value
Color - Visual Green
Density @15˚C g/cm3 ASTM D4052 0.85
Kinematic Viscosity @100˚C cSt ASTM D445 7.1
Kinematic Viscosity @40˚C cSt ASTM D445 30.9
Brookfield Viscosity @ -40°C mPa.s ASTM D2270 8900
Foam, Seq I @ 24°C ml-ml ASTM D892 0-0
Foam, Seq II @ 93.5°C ml-ml ASTM D892 10-0
Foam, Seq III @ 24°C ml-ml ASTM D892 0-0
https://www.idemitsulubricants.com/dA/76e4ed26b1/tds CVTF Type SB2-v2.pdf

Doesn't seem to have enough specs to make a matching fluid? Or does Amsoil do more tests to really get a clear picture of what the fluid is supposed to do and what it contains?
Is there a spec for oil "grippy-ness" or friction characteristics? I've never found one. Or the additive package? I assume there must be a bit of additive magic involved?

Also Idemitsu makes several CVT fluids' meeting only one or 2 manufacturer specs? Again, maybe they are chasing only small gains by having a fluid for each CVT fluid spec? I dunno, but I assume they do it for a reason?

I'm sure the Amsoil CVT fluid is "fine" and in a pinch I would use it if needed, but I'm still not convinced it is equal to CVT fluids designed to meet a specific spec. I'm sure if you looked up something simple like the range of viscosities on all the CVTF specs Amsoil meets, I might wonder the ones at the extremes are that viscosity for a reason, as often the CVT fluid spec is for a specific transmission, just like Subaru is doing?
 
I called Alec Wolffe of Idemitsu back in 2022. Funny, he used to work for Motul, where I called and spoke with him regarding Motul fluids as well a handful of years before that.

This is what he told me back in 2022.
Within Idemitsu there are two branches, one dealing with OEM fluids and one with aftermarket. Due to contracts, the OEM branch is not allowed to share the chemistry of this OEM fluid with the aftermarket till after three years. After those three years pass, they can then "unlock" the formulation and then the aftermarket side can develop an aftermarket fluid to meet the spec. So, the only option we 2020+ users have at this point is Subaru's Type III fluid, which is made my Idemitsu's OEM branch. He says in a couple years Idemitsu should have a fluid compatible with the OEM Type III fluid. He does not even know if the two fluids are compatible or even the differences. When asked if it could be simply for fuel economy, he said it could very well be, but we don't know. He said -if- the two fluids are different viscosities, there may be a difference in the CVT transmission itself. Therefore putting the wrong fluid in may cause issues with the "shifting".

Anyway, those with 2020+ CVT's....USE TYPE III.

I looked at Idemitsu and they still do not have a consumer product compatible with their OEM CVTF III fluid. SB2 is the same as the OEM CTVF II.
https://www.idemitsulubricants.com/product/cvtf-type-sb2
 
Find a new mechanic.

Use the OEM Subaru fluid. There are quite a lot of videos on Youtube and similar, describing the process.
I believe they have two different OEM fluids for the turbo vs. NA engines. Turbos make more torque. Those CVTs use different fluid I believe.

But I don't think any of the Crosstreks are turbos. But could be wrong.
 
I believe they have two different OEM fluids for the turbo vs. NA engines. Turbos make more torque. Those CVTs use different fluid I believe.

But I don't think any of the Crosstreks are turbos. But could be wrong.
There is a 2.5 L engine option, not particularly high torque. 178 vs. 145 Lb-Ft.
About what you would expect with 30 more cubic inches
 
So the question is - does Subaru make their own specifications, and if so - do they publish them. Which I would expect them to do.
The manf. of the transmission works with an additive company to develop the fluid specification. The transmission manf. and the additive company then work with a blender to blend the fluid to the final specifications. Some additive companies also produce the blended fluid for OEM factory fill and for sale to the public. Asian transmission manf. rarely publish fluid specifications.
And also - would a manufacturer omit some parameter from the specifications they publish, to throw a stick in the wheels of fluid manufacturers. Which sounds outlandish to me.
Logically, no, because this would cause all kinds of potential liabilities.
Asian manf. rarely publish fluid specifications.

If I, an additive manf. develop a replacement fluid, I have to analyze it thoroughly and test it in actual hardware and in a balanced formulation using tests such as the FZG wear test (ASTM D5182) and the JASO LVFA Anti-Shudder Durability Test.

The only thing you will see listed from a blender's Technical Data Sheet (TDS) is the fluid's bulk oil properties. Fluid bulk properties are not the fluid's specifications.
 
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See (2) Images below showing friction surfaces on the lineratronic TR690 "Chain Drive" style CVT.
IIRC there is also clutch pack in the fluid coupling that locks up at low rpm once you get moving that would require a specific FM along with the sheaves.

Screenshot 2025-04-12 120533.webp


Screenshot 2025-04-12 120657.webp
 
See (2) Images below showing friction surfaces on the lineratronic TR690 "Chain Drive" style CVT.
IIRC there is also clutch pack in the fluid coupling that locks up at low rpm once you get moving that would require a specific FM along with the sheaves.
Any ATF fluid is a complex combination of at least 18 separate chemistries.

A CVT fluid has to have a group of friction modifiers to satisfy both the traction coefficient for the chain/pulley system and the frictional requirements for the torque converter/lockup clutch.
 
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And that is something that aftermarket fluid manufacturers won't know and be completely oblivious to ? Who brews the fluid for the car manufacturer?

Car manufacturers' track record about CVT transmissions is not exactly spotless, reliability-wise.
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Exactly this.

Have you heard of the Nissan CVT troubles some people have been having over the last ten years or so? How about the GT-R DCT transmission failures, shutdowns, explosions?

The $30-80 (per quart / liter) transmission fluid they have been selling and recommend is not helping unless you ignore their service recommendations and protect yourself against the mfg.
 
Any ATF fluid is a complex combination of at least 18 separate chemistries.

A CVT fluid has to have a group of friction modifiers to satisfy both the traction coefficient for the chain/pulley system and the frictional requirements for the torque converter/lockup clutch.
So its not likely that a single CVT fluid is going be optimal for many many different CVT transmissions? Especially puller vs pusher types?
 
So its not likely that a single CVT fluid is going be optimal for many many different CVT transmissions? Especially puller vs pusher types?
Puller and pusher both rely on traction from pulley to belt. The rest of the transmission is basically the same which overlaps with AT requirements.

ie, a CVT requires an ATF with the additional requirements of belt / pulley traction. Otherwise, they both use same components (pumps, bearings, seals, clutches, torque converter, gears, chains, solenoids, valves, filters, magnets, etc).
 
On my Honda HRV I change the CVT fluid every 30000 miles and stick to Honda OEM CVT fluid...Its not like you are changing the fluid every 5000 miles or so...
 
On my Honda HRV I change the CVT fluid every 30000 miles and stick to Honda OEM CVT fluid...Its not like you are changing the fluid every 5000 miles or so...
For the most part the OEM fluids are "fine". The trouble starts when service is neglected especially in the first year to three (~10k miles).

CVTs will not tolerate the same metal contamination in the fluid as a typical AT will. The fluid is clamped between the belt and pulleys where there is a small amount of continuous slip. Any metal contamination will rapidly wear the belt leading to rapid increase in metal contamination in the fluid and runaway deterioration of the whole CVT. The media filters and screens in the transmission are not designed to capture the wear metal, only the worst offenders (rock catchers). The addition of magnets (and "extra magnets") is what keeps the fluid serviceable as these magnetic filters are actively functioning 24hrs a day. As the magnets load up they are reduced in efficiency, this is why it is important to keep them clean in the first few years while the transmission is wearing in.

Keep the pan and magnets clean and the CVT, or any transmission, will last a long time. Follow the mfg service recommendations at your own peril.
 
For the most part the OEM fluids are "fine". The trouble starts when service is neglected especially in the first year to three (~10k miles).

CVTs will not tolerate the same metal contamination in the fluid as a typical AT will. The fluid is clamped between the belt and pulleys where there is a small amount of continuous slip. Any metal contamination will rapidly wear the belt leading to rapid increase in metal contamination in the fluid and runaway deterioration of the whole CVT. The media filters and screens in the transmission are not designed to capture the wear metal, only the worst offenders (rock catchers). The addition of magnets (and "extra magnets") is what keeps the fluid serviceable as these magnetic filters are actively functioning 24hrs a day. As the magnets load up they are reduced in efficiency, this is why it is important to keep them clean in the first few years while the transmission is wearing in.

Keep the pan and magnets clean and the CVT, or any transmission, will last a long time. Follow the mfg service recommendations at your own peril.

I'm quite certain that this is wrong.

The filters are there to collect metal particles. I know that on my Honda CVT there are two different paper filter elements.

And the biggest risk with metal particles in the oil is plugging up the valve body, not direct friction on the sheaves and belts.
 
I'm quite certain that this is wrong.
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Think whatever you like. The facts are:

- CVT steel belts are clamped in steel pulleys under high pressure
- CVT fluid provides the traction required for torque transmission
- the belt is continuously slipping (slowly) during torque transfer
- there is a continuous shedding of steel from the belt and pulleys, especially under break-in
- the more metal in the fluid the higher the wear rate
- the filters are nowhere near large or fine enough to capture this material and prevent excessive wear
- CVTs and ATs have had increasing number (or size) of magnets introduced as updates or in newer models... I wonder why?
 
Think whatever you like. The facts are:

- CVT steel belts are clamped in steel pulleys under high pressure
- CVT fluid provides the traction required for torque transmission
- the belt is continuously slipping (slowly) during torque transfer
- there is a continuous shedding of steel from the belt and pulleys, especially under break-in
- the more metal in the fluid the higher the wear rate
- the filters are nowhere near large or fine enough to capture this material and prevent excessive wear
- CVTs and ATs have had increasing number (or size) of magnets introduced as updates or in newer models... I wonder why?
Debris management has increased with new transmission, so the bits can be kept out of the valve body, pump, oil cooler, variators, and other critical parts. CVT's don't blow up because the sheaves wear from gritty oil.
 
Debris management has increased with new transmission, so the bits can be kept out of the valve body, pump, oil cooler, variators, and other critical parts. CVT's don't blow up because the sheaves wear from gritty oil.
They actually do. Or, they tend to outlast the rest of the car (300k miles minimum) if they have been properly maintained.
 
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