Ranking of ATF Fluids?

[martinq]

From decades of experience and the lack of any significant evidence of failure, it's clear to me that products like Valvoline MaxLife ATF exceed the functional requirements of ALL the applications on their respective data sheet. If this was not true they would be out of business in short order or their product would need to be so obscure to evade any significant legal attention and public scrutiny.

There are no OEM fluids that I know of that can meet the operating performance of these multi-ATF fluids and the majority are significantly more expensive. Because of this I haven't used, or recommended, an OEM fluid of any kind for well over a decade unless it was an unbeatable value. I can't see how this would change anytime soon.

 

[MolaKule]

"...The Advanced friction modifiers provide superior anti-shudder performance and consistent shifting across different clutch materials and technologies, spanning from older DEXRON/MERCON requirements to modern low-viscosity fluids..."

I would say this is one of the secrets to the success of broad-spectrum step-shift transmission ATFs,

A lot of R&D and hardware testing by the additive suppliers was involved in validating the proper Mu(v) for various transmissions.

Post in thread 'Friction Modifiers (FMs)'

Jul 7, 2019

Let's start with the definition of Static Friction since friction is an often misunderstood topic.

As with any definition of friction we must remember that friction is surface (interfacial) dependent, that is, friction is dependent on the types of surfaces under consideration for the surfaces in the system.

Static Friction is that force that opposes movement, i.e., there is no movement and the static friction force holds an object motionless unless a greater force is applied to overcome it which then results in Dynamic Friction (friction due to motion). Every system...

• MolaKule

 

[skaughtz]

I would say this is one of the secrets to the success of broad-spectrum step-shift transmission ATFs,

A lot of R&D and hardware testing by the additive suppliers was involved in validating the proper Mu(v) for various transmissions.

Post in thread 'Friction Modifiers (FMs)'

Jul 7, 2019

Let's start with the definition of Static Friction since friction is an often misunderstood topic.

As with any definition of friction we must remember that friction is surface (interfacial) dependent, that is, friction is dependent on the types of surfaces under consideration for the surfaces in the system.

Static Friction is that force that opposes movement, i.e., there is no movement and the static friction force holds an object motionless unless a greater force is applied to overcome it which then results in Dynamic Friction (friction due to motion). Every system...

• MolaKule

I mean... maybe? But if the Fight Club recall coordinator's formula is real, how does that explanation give you any confidence? Take the number of vehicles in the field, A, multiplied by the probable rate of failure, B, then multiply the result by the average out of court settlement, C. A*B*C=X. If X is less than the cost of promoting "universal" applicability, they don't do it. Nothing in their answer gives me confidence that some nerd didn't do the cost/benefit math to determine that they make more money applying it to more transmissions than not.

 

[CleanSump]

I mean... maybe? But if the Fight Club recall coordinator's formula is real, how does that explanation give you any confidence? Take the number of vehicles in the field, A, multiplied by the probable rate of failure, B, then multiply the result by the average out of court settlement, C. A*B*C=X. If X is less than the cost of promoting "universal" applicability, they don't do it. Nothing in their answer gives me confidence that some nerd didn't do the cost/benefit math to determine that they make more money applying it to more transmissions than not.

Don't trust them then us something else. Freedom to choose is an amazing thing.

 

[MolaKule]

...Nothing in their answer gives me confidence that some nerd didn't do the cost/benefit math to determine that they make more money applying it to more transmissions than not.

No, no nerd conspiracies. It's actually a milestone advancement in ATF chemistry that allows a broad spectrum ATF to be developed.

 

[skaughtz]

No, no nerd conspiracies. It's actually a milestone advancement in ATF chemistry that allows a broad spectrum ATF to be developed.

I hope that you are correct. And in all likelihood, you are. But when it comes to my multi-thousand dollar transmission, I'm just not taking them at their incredibly vague word on it without answering what I thought was a rather concise question. "Super-duper additives" doesn't do it for me when I'm asking for physics.

 

[MolaKule]

I hope that you are correct. And in all likelihood, you are. But when it comes to my multi-thousand dollar transmission, I'm just not taking them at their incredibly vague word on it without answering what I thought was a rather concise question. "Super-duper additives" doesn't do it for me when I'm asking for physics.

What physics or chemistry question(s) are you asking? Please be specific.

 

[4329]

I would say this is one of the secrets to the success of broad-spectrum step-shift transmission ATFs,

A lot of R&D and hardware testing by the additive suppliers was involved in validating the proper Mu(v) for various transmissions.

Post in thread 'Friction Modifiers (FMs)'

Jul 7, 2019

Let's start with the definition of Static Friction since friction is an often misunderstood topic.

As with any definition of friction we must remember that friction is surface (interfacial) dependent, that is, friction is dependent on the types of surfaces under consideration for the surfaces in the system.

Static Friction is that force that opposes movement, i.e., there is no movement and the static friction force holds an object motionless unless a greater force is applied to overcome it which then results in Dynamic Friction (friction due to motion). Every system...

• MolaKule

Would it be possible as the resident expert to explain the effect viscosity differences may have on automatic transmission shift quality in terms of timing and harshness and explain the following table.This may help people understand ATF specifications and perhaps reduce the amount of c#ap posted on the internet.
s
Density at 15°C, kg/L

Viscosity, Kinematic, cSt at 40°C

Viscosity, Kinematic, cSt at 100°C

Viscosity Index 147

Viscosity, Brookfield, cSt @ -40°

 

[daniel327]

All of which leads me to believe that it probably doesn't matter what ATF you use as long as you keep it clean.

You might be right.

 

[skaughtz]

What physics or chemistry question(s) are you asking? Please be specific.

I am not trying to be a know-it-all. I legitimately want an answer to this question because it serves me better as a consumer. But I'm not for everyone, so thanks for engaging.

To address your question, for example, transmission valve bodies are built around specific hydraulic properties of the specified ATF. One would assume that any deviation from those paramaters would lead to variations in performance. Thus the quandary of how universal fluids can function equivalently to specified ATFs that possess different fluid characteristics? It isn't a question of additives, it is a question of the physics inherent in the design of the transmission.

 

[MolaKule]

Would it be possible as the resident expert to explain the effect viscosity differences may have on automatic transmission shift quality in terms of timing and harshness and explain the following table.This may help people understand ATF specifications and perhaps reduce the amount of c#ap posted on the internet.
s
Density at 15°C, kg/L

Viscosity, Kinematic, cSt at 40°C

Viscosity, Kinematic, cSt at 100°C

Viscosity Index 147

Viscosity, Brookfield, cSt @ -40°

Shift quality is determined by two main factors: the Mu(v) and programming.

 

[MolaKule]

...To address your question, for example, transmission valve bodies are built around specific hydraulic properties of the specified ATF.

Which hydraulic properties? Valve bodies route fluid and control shift timing as programmed by the TCU.

W would assume that any deviation from those paramaters would lead to variations in performance. Thus the quandary of how universal fluids can function equivalently to specified ATFs that possess different fluid characteristics?

What fluid characteristics?

It isn't a question of additives, it is a question of the physics inherent in the design of the transmission.

As explained in at least two previous posts, multi-vehicle coverage in ATFs is done by the selection of specific friction modifier chemistry.

 

[4329]

Shift quality is determined by two main factors: the Mu(v) and programming.

Shift quality is determined by two main factors: the Mu(v) and programming.

Thank you for your response. Does the transmission computer relearn to account for a different viscosity ATF to then control shift, if this is the case then any ATF brand could be used with regard to its different viscosity to the OEM and the main issue would be the additive package.

 

[ctechbob]

I am not trying to be a know-it-all. I legitimately want an answer to this question because it serves me better as a consumer. But I'm not for everyone, so thanks for engaging.

To address your question, for example, transmission valve bodies are built around specific hydraulic properties of the specified ATF. One would assume that any deviation from those paramaters would lead to variations in performance. Thus the quandary of how universal fluids can function equivalently to specified ATFs that possess different fluid characteristics? It isn't a question of additives, it is a question of the physics inherent in the design of the transmission.

You're forgetting temperature. They have to operate over a wide range of them and thus viscosities. Otherwise you'd have to wait for them to warm up completely on a 0 degree morning before you could move them. There's usually enough 'wiggle room' in the TCU programming to deal with slightly different viscosities. Be that through line pressure changes, or shift timing changes.

 

[daniel327]

................... multi-vehicle coverage in ATFs is done by the selection of specific friction modifier chemistry.

What's your opinion on adding Lube Gard's Highly Friction Modified ATF Supplement to a compatible viscosity base fluid?

https://lubegard.com/product/highly-friction-modified-atf-hfm-atf-supplement-with-lxe-technology/

 

[GW.]

You're forgetting temperature. They have to operate over a wide range of them and thus viscosities. Otherwise you'd have to wait for them to warm up completely on a 0 degree morning before you could move them. There's usually enough 'wiggle room' in the TCU programming to deal with slightly different viscosities. Be that through line pressure changes, or shift timing changes.

BINGO!!

Just like engine oil, transmission fluid viscosity is affected much more by temperature than whats on the spec sheet. Transmissions also have to operate with a wide range of viscosities. Towing or cold weather in my vehicles equal 20-30f or more swings in fluid temperature.

 

[melk]

I just finished 3x spill/fill on my 07 CRV using DW-1 but seems like MaxLife (or Valvoline Restore and Protect ATF) would be a fine choice. Fluid was still quite dark after the 3rd drain so I’ll probably do another at next oil change.

Next up is my son’s 2013 Hyundai. I’ve done one fill of MaxLife already and based on fluid color definitely needs some follow ups as well.

 

[amateurbob]

I just finished 3x spill/fill on my 07 CRV using DW-1 but seems like MaxLife (or Valvoline Restore and Protect ATF) would be a fine choice. Fluid was still quite dark after the 3rd drain so I’ll probably do another at next oil change.

Next up is my son’s 2013 Hyundai. I’ve done one fill of MaxLife already and based on fluid color definitely needs some follow ups as well.

Do you have any idea how long it has been since the fluid was changed?

 

[martinq]

Thank you for your response. Does the transmission computer relearn to account for a different viscosity ATF to then control shift, if this is the case then any ATF brand could be used with regard to its different viscosity to the OEM and the main issue would be the additive package.

The difference in viscosity is not significant so I don't think there would be anything in the code to adjust to such minute differences. The transmission will function when the fluid is 1000cSt or 10cSt. The difference between ATF available is fairly small (maybe 5-20% ?) and the transmission can cope with orders of magnitude difference.

Regardless of which fluid you use, it needs to be kept clean (clean your pan & magnets if you can) and cool (monitor the temperature). Minor viscosity differences are for OEM fuel efficiency benefits / targets.

 

[UGASpike]

@skaughtz what email did you reach out to at Valvoline? I email their support@ email and have not heard back.

You're forgetting temperature. They have to operate over a wide range of them and thus viscosities. Otherwise you'd have to wait for them to warm up completely on a 0 degree morning before you could move them.

This tracks with what I reached out to Valvoline about. I was curious to why their Maxlife atf, and Extended performance not meet ULV but their Restore and protect meet it?

All 3 mentioned above have a kv100 at 5.9 but Valvoline Restore and Protect hold the recommended for ULV which is a whopping 4.5.

Now I understand the difference between 1.4 cst is little to nothing. Additive package is the only thing that would make sense.