High Torque, Low Viscosity Multi Vehicle CVT Fluid Tech Discussion

[jim302]

The vehicle in question is a 2023 Subaru Outback 2.4L Turbo with the TR690 CVT, but I'm interested in having a primarily technical discussion about fluid so this could apply to other vehicles which specify a "high torque" and/or low viscosity CVT fluid.

OE would be the "safe" choice, but Subaru likes to sell their fluid in 5 gallon buckets and they have 4 types. Yet there are aftermarket fluids that claim compatibility with multiple specs, with Amsoil, Valvoline and LubeGard claiming the widest range of matches.

So first, what makes a CVT fluid suitable for high torque applications? Initial theories:

• It is simply branding / marketing... but some fluids specifically state that they are not for use in high torque applications so that leads me to believe there is a real design difference
• Better quality base oils to resist oxidation and shear in high heat / high load applications
• Higher dose of friction modifiers and additives, or possibly a completely different additive chemistry

If the main difference is base oil, then clearly it would be quite easy for a fluid to match the HT and standard applications (for example, Subaru High Torque CVTF and Subaru CVTF II). Different additive chemistries seem like a higher risk, especially during a simple drain and fill where half of the original fluid is left behind.

The second piece of the puzzle is viscosity. While it is relatively easy to find aftermarket solutions for LV and ULV applications in step shift applications, CVT fluid seems to be a one size fits all thing in North America. Interestingly, there are several dedicated LV CVT fluids in the Australian market.

• How big of a deal is it to use a somewhat higher viscosity fluid (such as Amsoil, with a cSt of about 7.1@100°C where the OE fluid may be closer to 5.5 cSt)?
• The same applies in reverse, but seems like less of a concern considering that used oil analysis indicate that the OE fluids often shear to this level during normal use, and these fluids should be more shear stable.

I'm interested in hearing thoughts and theories, as well as experiences with aftermarket fluids in high torque and/or low viscosity applications.

• How can aftermarket companies claim such broad matches? Is it just that OE manufacturers only validate one fluid type and recommend that to be on the safe side?
• Are CVTs as finicky as people suggest on fluids? Fear Uncertainity and Doubt are quite common, but rarely if ever does anyone post any definitive evidence to back up their claims that Amsoil, Valvoline, etc harmed a transmission.
• Which would you rather have? Dirty, oxidized and sheared OE fluid or at least some fresh aftermarket fluid that is not an exact match in viscosity or additve chemistry?

 

[LazyDog]

I would first consider the internals of the CVT since it seems they where few variations of Jatco/ Nissan's CVT's.

I believe they where the belt and chain driven CVT's like on the Maxima cars.

This was just something else to consider.

 

[SC Maintenance]

Given a CVT can use a torque converter or not, or can use a use hydraulic or electric pulley actuators or not - the answer regarding viscosity might be CVT design specific?

Also given there is a chain involved, I would guess the add pack is also very important.

I generally don't like aftermarket AT fluids, at least not the ones that supposedly meet every spec on earth, for these reasons.

What do the subi boards say?

 

[Passport1]

Just my personal anecdote so it adds nothing empirically. I have a 2012 Suzuki bought new. Early on while driving on hwy 95 in south Florida one sultry summer night the CVT overheated and the car went into limp mode. Let it cool down and got to my destination. It happened again on the way back to NC but I caught it earlier. A dealer reflashed the computer and that helped a bit but the CVT (jatco) began to whine. I decided to change the fluid and subbed in 4 quarts of Valvoline CVT fluid (actually amber not green color) I did that about three more times and now I calculate about a 90% exchange of the OE fluid. I plan to do this again soon. All this cvt talk makes me want a newer car, this time with a third pedal.

No more CVT trouble.

 

[D60]

I just did a spill 'n fill on a '15 TR580 with the Castrol Universal "nearly everything" fluid. They do claim it's compatible for chains/CVTF-II

I only did a single drain. Got about 5.5qts out and put 6 back in per the proper procedure.

I dunno, it seems fine. Then again I rarely drive the vehicle (not mine) and that transmission always seems a little weird to me.

 

[jim302]

What do the subi boards say?

They aren't a great place for technical information about lubrication, like most brand/model specific forums. There have been success stories for Amsoil and Valvoline, but nothing about long term use vs. just leaving the factory fill in forever until the transmission dies or something else happens that is not worth fixing.

One poster claims to have seen multiple CVTs that were immediately destroyed by Amsoil (and also by dealers using the regular High Torque fluid in HT-LV applications). Of course he can't post any specific examples and is being really dramatic about everything, so I believe him about as much as I believe the random people on the Internet that claim to have seen dozens of engines (sometimes more) destroyed by FRAM filters... so not at all.

Still, it is a little hard to not be suspicious about claims of such broad matches without more information to back it up. I wouldn't hesitate to use these fluids in a Jatco push belt style CVT since Amsoil and others have actual test data on these. I don't want to give in to fear mongering on the Subaru forums, because then either I leave the factory fill in or have to pay $500 for a 5 gallon bucket (commonly out of stock), and hope I can sell the leftovers to someone else.

Dealer service is probably a no-go, since most refuse to touch the CVT and I honestly trust myself to follow the instructions in the factory service manual more than I would trust a flat rate tech I never met that is trying to beat book time.

 

[MolaKule]

The vehicle in question is a 2023 Subaru Outback 2.4L Turbo with the TR690 CVT, but I'm interested in having a primarily technical discussion about fluid so this could apply to other vehicles which specify a "high torque" and/or low viscosity CVT fluid.

What engines are considered high torque for CVT couplings?

Most CVT fluids in the US are around 7.1-7.3 cSt@100C. WHich Autralian CVT fluids are of lower viscosity?

 

[jim302]

What engines are considered high torque for CVT couplings?

Subaru uses the High Torque CVT fluid for when the engine is a H6 3.6R (EZ36D) or H4 2.4L (FA24) which produce between 247 and 277 lb⋅ft of torque. They claim up to 3,500 lbs of towing capacity on some models.

Most CVT fluids in the US are around 7.1-7.3 cSt@100C. WHich Autralian CVT fluids are of lower viscosity?

I may have mixed up some product data sheets. Atlantic Oil CVT Ultra-Syn Low Viscosity shows a cSt of 7.09 on the PDS but 5.6 on the SDS. Penrite claims a cSt of 5.6 but is not suitable for chain type CVTs.

Upon further review, the PDS for Valvoline's US market CVT fluid says it has a cSt of 5.6... so it is interesting to see the discrepancy in viscosity between brands claiming to meet the same specs. I can't find the viscosity of LubeGard.

Of course I'd really like to know the viscosity of the OE fluid, but that is impossible to find as the SDS from ENEOS just says ">20.5(mm2/sec)(40℃)" for both the High Torque and High Torque LV fluids. Not very useful...

 

[MolaKule]

Subaru uses the High Torque CVT fluid for when the engine is a H6 3.6R (EZ36D) or H4 2.4L (FA24) which produce between 247 and 277 lb⋅ft of torque. They claim up to 3,500 lbs of towing capacity on some models.

I may have mixed up some product data sheets. Atlantic Oil CVT Ultra-Syn Low Viscosity shows a cSt of 7.09 on the PDS but 5.6 on the SDS. Penrite claims a cSt of 5.6 but is not suitable for chain type CVTs.

Upon further review, the PDS for Valvoline's US market CVT fluid says it has a cSt of 5.6... so it is interesting to see the discrepancy in viscosity between brands claiming to meet the same specs. I can't find the viscosity of LubeGard.

Of course I'd really like to know the viscosity of the OE fluid, but that is impossible to find as the SDS from ENEOS just says ">20.5(mm2/sec)(40℃)" for both the High Torque and High Torque LV fluids. Not very useful...

Yes, there is a discrepancy between the Atlantic PDS and the SDS. It could be the formula was changed and the PDS has not yet been updated.

Our Nissan Pathfinder's 3.5L V6 produces about 265 lb.ft of torque and I have always used a CVT fluid of 7.1 to 7.3 cSt and the CVT has over 120,000 miles on it. I have it changed every 6 months.

 

[benjy]

CVT upkeep is critical as a repair ?? replacement is close to a new engine $$$$ i will NEVER own one!!! my car + truck are both 6 spd MANUALS!!!

 

[martinq]

The vehicle in question is a 2023 Subaru Outback 2.4L Turbo with the TR690 CVT, but I'm interested in having a primarily technical discussion about fluid so this could apply to other vehicles which specify a "high torque" and/or low viscosity CVT fluid.

OE would be the "safe" choice, but Subaru likes to sell their fluid in 5 gallon buckets and they have 4 types. Yet there are aftermarket fluids that claim compatibility with multiple specs, with Amsoil, Valvoline and LubeGard claiming the widest range of matches.

So first, what makes a CVT fluid suitable for high torque applications? Initial theories:

• It is simply branding / marketing... but some fluids specifically state that they are not for use in high torque applications so that leads me to believe there is a real design difference
• Better quality base oils to resist oxidation and shear in high heat / high load applications
• Higher dose of friction modifiers and additives, or possibly a completely different additive chemistry

If the main difference is base oil, then clearly it would be quite easy for a fluid to match the HT and standard applications (for example, Subaru High Torque CVTF and Subaru CVTF II). Different additive chemistries seem like a higher risk, especially during a simple drain and fill where half of the original fluid is left behind.

The second piece of the puzzle is viscosity. While it is relatively easy to find aftermarket solutions for LV and ULV applications in step shift applications, CVT fluid seems to be a one size fits all thing in North America. Interestingly, there are several dedicated LV CVT fluids in the Australian market.

• How big of a deal is it to use a somewhat higher viscosity fluid (such as Amsoil, with a cSt of about 7.1@100°C where the OE fluid may be closer to 5.5 cSt)?
• The same applies in reverse, but seems like less of a concern considering that used oil analysis indicate that the OE fluids often shear to this level during normal use, and these fluids should be more shear stable.

I'm interested in hearing thoughts and theories, as well as experiences with aftermarket fluids in high torque and/or low viscosity applications.

• How can aftermarket companies claim such broad matches? Is it just that OE manufacturers only validate one fluid type and recommend that to be on the safe side?
• Are CVTs as finicky as people suggest on fluids? Fear Uncertainity and Doubt are quite common, but rarely if ever does anyone post any definitive evidence to back up their claims that Amsoil, Valvoline, etc harmed a transmission.
• Which would you rather have? Dirty, oxidized and sheared OE fluid or at least some fresh aftermarket fluid that is not an exact match in viscosity or additve chemistry?

I've had years of experience with the 2010 JATCO CVT used in Nissan Cube/Versa (jf009e, AKA CVT1). Maxlife ATF/CVT, Recochem "OEM" CVT and Amsoil CVT fluids all seem to work well.

To me the most important thing is clean, "cool" fluid, and keeping it that way. Drop the pan, clean it (and the magnets!) annually and you'll probably get long life and few issues.

Every CVT system is unique in some way so it's best to get to know yours and it's quirks or weaknesses. Get access to the TSBs for your make/model and look for clues.

 

[D1dad]

I tried lubegaurd in my 2018 rogue and it ran about 10 degrees warmer than eneos, Oem or idemitsu. I did a total drain and fill via the line going to the radiator with Oem and the temps came back down. Lubeguard poured thicker than others as well. I used valvoline in my 09 consistently and just did a line flush on my nieces 17 Altima and never an issue.

 

[TacoFergie]

Hate to bring threads back from the dead. But did you ever come up with anything on this subject? I have an Ascent that I've been wanting to do a drain and fill on, but I have a hard time justifying the cost and quantity of the OE fluid.

 

[martinq]

What year Ascent?

I would not hesitate to use Valvoline, Castro, Amsoil fluid in that transmission as long as the system is clean and not overheating.

Valvoline MaxLife ATF lists most of the Subaru applications, including the requirements of the TR690 Lineartronic CVT:

Lineartronic High Torque (HT) CVT Fluid, CV-30, K0425Y0710

 

[TacoFergie]

What year Ascent?

I would not hesitate to use Valvoline, Castro, Amsoil fluid in that transmission as long as the system is clean and not overheating.

Valvoline MaxLife ATF lists most of the Subaru applications, including the requirements of the TR690 Lineartronic CVT:

Lineartronic High Torque (HT) CVT Fluid, CV-30, K0425Y0710

Negative... the TR690 behind the FA24DIT in the Ascent, Outback, Legacy and WRX use CVTF-LV SOA748V0300. The previous one in the 3.6R Outback used SOA748V0200 which is not cross-compatible.

At this time, I am unaware of any aftermarket fluid that is truly compatible CVTF-LV SOA748V0300. Valvoline CVT and Amsoil CVT claims to be compatible, some of the Subaru "experts" on the various forums claim it isn't though. Also it doesn't make sense viscosity wise how 2 different "compatible" fluids can have significantly different values
Valvoline CVT - 5.6cSt @ 100C
Amsoil CVT - 7.3cSt @ 100C
Castrol Import - 7.4cSt @ 100C (also claims it works in ALL Subaru transmissions, that includes the old 4 speed to the newest....no way)

I don't know if using a different fluid would cause issues? Some claim aftermarket fluid WILL cause a failure in short time, while others don't. But I don't know of any verified users of any aftermarket fluid long term. If someone does have long term use experience of an aftermarket fluid in the TR690, I'd love to hear their experience.

 

[martinq]

Negative... the TR690 behind the FA24DIT in the Ascent, Outback, Legacy and WRX use CVTF-LV SOA748V0300. The previous one in the 3.6R Outback used SOA748V0200 which is not cross-compatible.
...

In light of this information, and understanding that the vast majority of CVT applications are similar and covered by Multi-ATF / Multi-CVT fluids, I would start by using Valvoline MaxLife ATF.

Far more important than the specific fluid is the system cleanliness and fluid temperature. I've never come across a CVT or AT failure that was attributed to the use of a reliable mfg recommended fluid. It is almost ALWAYS due to insufficient maintenance or design / mfg defects.

 

[TacoFergie]

In light of this information, and understanding that the vast majority of CVT applications are similar and covered by Multi-ATF / Multi-CVT fluids, I would start by using Valvoline MaxLife ATF.

Far more important than the specific fluid is the system cleanliness and fluid temperature. I've never come across a CVT or AT failure that was attributed to the use of a reliable mfg recommended fluid. It is almost ALWAYS due to insufficient maintenance or design / mfg defects.

The issue is, no one really knows what’s special about the CVTF-LV. I know fluid color is seemingly irrelevant, but it can cause issues with warranty if they “determine” a failure was due to improper fluid used. I know that can fought, but it could be a time consuming battle leaving you without a vehicle for quite some time possibly. Plus if you loose said battle, it’s a $10k transmission that you can only buy new from Subaru, no reman units out there.

I’ve never seen a used oil analysis or VOA of CVTF-LV SOA748V0300 and I’m not sure it would really reveal much besides viscosity which of course doesn’t tell the whole story anyways. It’s really a gamble with an already finicky transmission.

While I agree that Maxlife is a fantastic all around transmission fluid, it does not claim that it is compatible with the CVTF-LV.

Maybe there are other members here that have experience with this transmission or lubricant manufactures that would be willing to chime in? The Subaru needs on the Ascent and Outback forums are very cautious about alternative fluids being used, some with supposed inside info.

 

[GSCJR]

You're looking at the step shift portion of the PDS. The MaxLife PDS clearly states it is suitable for HT (high torque), albeit not the LV variant, applications under the CVT subheading. Alternatively, Valvoline also has a dedicated CVT fluid available (blue bottle), which is suitable for use in CVT where a LV fluid is recommended.

 

[martinq]

The LV & ULV formulas for CVT and AT are used to gain some fuel efficiency points to help with marketing and CAFE requirements. The downside is reduced viscosity / temperature protection and shorter service life. One upside is in operating in extreme cold environments.

There is no "magic" in using a slightly thinner fluid, it reduces drag and parasitic loss. The trade off is protection and wear.

You will not go wrong in using a cost effective fluid like those from Valvoline or a high performance fluid from Amsoil. No transmission has ever been lost or damaged by using an appropriate fluid from these companies or else we would hear about the lawsuits (likely class-action).

 

[shadetreeguy]

The new 690 stinks anyway, so fluid type ain't gonna matter. There is a huge amount of recalls on the HT 690 and a class action suit. My 2019 ascent got a new transmission when it failed the recall test at 68k. Subaru covered it, but will not touch anything with any cvt's in Huntsville AL. They keep saying that it is a lifetime cvt. They are correct in their opinion cause it will crap out and that's the lifetime. My first and last Subaru, I wouldn't take anything they have. They are the most overrated vehicles on the market. The engines will definitely outlast the car around it. So I am saying that you could put oily water in the cvt and it will be as good as SOA oem bull crap, highway robbery to charge $40 a quart for special fluid. I've been using Castrol transmax universal for 170k just drain and fill every 40k.