If you like to service your AT, stay off the Lexus forums.
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Transmission fluid lifetime
- Thread starter Bill_W
- Start date
Originally Posted by hallstevenson
Originally Posted by Bill_W
As far as sealed transmission, from what others have said if there is no dipstick it is that definition. But what does anyone know?
That is one "condition" that frequently seems applied for sealed transmissions, i.e. lifetime fluid.
Dig deeper into your owner's manual and look for a "severe service" schedule. Those will often give mileages to change or at least inspect fluids, filters, etc.
^^^^^^^^^^^^^
This is accurate in my observation... My car manual does exactly what hall mentions above.
Originally Posted by Bill_W
As far as sealed transmission, from what others have said if there is no dipstick it is that definition. But what does anyone know?
That is one "condition" that frequently seems applied for sealed transmissions, i.e. lifetime fluid.
Dig deeper into your owner's manual and look for a "severe service" schedule. Those will often give mileages to change or at least inspect fluids, filters, etc.
^^^^^^^^^^^^^
This is accurate in my observation... My car manual does exactly what hall mentions above.
Originally Posted by MolaKule
As of right now there is no such thing as a Lifetime ATF.
There certainly is and it's probably the most common ATF out there. Plenty of vehicles use the same ATF that the factory put in them until the day they die (of something other than transmission failure). In those cases, that ATF is/was a "lifetime fluid."
As of right now there is no such thing as a Lifetime ATF.
There certainly is and it's probably the most common ATF out there. Plenty of vehicles use the same ATF that the factory put in them until the day they die (of something other than transmission failure). In those cases, that ATF is/was a "lifetime fluid."
Lifetime fluid has been mentioned for decades, nothing new. I remember an old 69 Plymouth I once owned. It was stated in the manual that the transmission fluid " would provide satifactory lubrication and periodic fluid changes are not required unless the vehicle's operation was considered severe".
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MolaKule
Staff member
Originally Posted by hallstevenson
Originally Posted by MolaKule
As of right now there is no such thing as a Lifetime ATF.
There certainly is and it's probably the most common ATF out there. Plenty of vehicles use the same ATF that the factory put in them until the day they die (of something other than transmission failure). In those cases, that ATF is/was a "lifetime fluid."
Please frame your response in terms of ATF chemistry because there certainly is not a lifetime fluid.
The chemistry of modern ATF's starts to degrade after about 30k miles.
Lifetime is an OEM gimmick to make the owner think that his maintenance costs will be lower simply because the tranny is essentially a sealed system.
Fluid degradation does not care what the OEM claims. ATF is cycled between extreme cold and hot cycles. Temp peaks oxidize the fluid even though we use the best anti-oxidants available today but anti-oxidants only last a finite time.
Clutch materials and metals increase the particulate load and modify the coefficient of friction over time as well as increase pump wear.
Temp cycles and temp peaks degrade the fluid's friction modification chemistry even though we use the best friction modification chemistry available today but friction modifiers only last a finite time as well.
Open up an AT tranny that has not had its fluid changed during its so-called "Lifetime" and you will see extreme varnishing of the valves, very dark and thick fluid, and gear and bearing wear.
Originally Posted by MolaKule
As of right now there is no such thing as a Lifetime ATF.
There certainly is and it's probably the most common ATF out there. Plenty of vehicles use the same ATF that the factory put in them until the day they die (of something other than transmission failure). In those cases, that ATF is/was a "lifetime fluid."
Please frame your response in terms of ATF chemistry because there certainly is not a lifetime fluid.
The chemistry of modern ATF's starts to degrade after about 30k miles.
Lifetime is an OEM gimmick to make the owner think that his maintenance costs will be lower simply because the tranny is essentially a sealed system.
Fluid degradation does not care what the OEM claims. ATF is cycled between extreme cold and hot cycles. Temp peaks oxidize the fluid even though we use the best anti-oxidants available today but anti-oxidants only last a finite time.
Clutch materials and metals increase the particulate load and modify the coefficient of friction over time as well as increase pump wear.
Temp cycles and temp peaks degrade the fluid's friction modification chemistry even though we use the best friction modification chemistry available today but friction modifiers only last a finite time as well.
Open up an AT tranny that has not had its fluid changed during its so-called "Lifetime" and you will see extreme varnishing of the valves, very dark and thick fluid, and gear and bearing wear.
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The Skyactiv Drive is not sealed and can be serviced. The pan has a drain plug and there is a small plastic dipstick held in by a single small bolt. I did a D&F on mine at 60,000 miles because I was guilted into it on this forum. The fluid I drained out was almost in like new condition. I refilled with the correct OEM fluid (Mazda FZ) and don't plan to touch it again.
MolaKule
Staff member
Sealed or not sealed, the Visual condition of a fluid tells you nothing about its remaining chemical condition.
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Originally Posted by MolaKule
hallstevenson said:
From the manufacturers of transmission ZF and the myth of lifetime fluid debunked.
https://youtu.be/D0f3AYoE3cI
https://youtu.be/D0f3AYoE3cI
Originally Posted by MolaKule
Please frame your response in terms of ATF chemistry because there certainly is not a lifetime fluid.
Not necessary. This discussion is about the real world. Doesn't matter if the fluid degrades or how much it degrades. If the fluid doesn't destroy the machinery and the machinery dies for reasons unrelated to the fluid, it "works" (and works for a "lifetime").
Please frame your response in terms of ATF chemistry because there certainly is not a lifetime fluid.
Not necessary. This discussion is about the real world. Doesn't matter if the fluid degrades or how much it degrades. If the fluid doesn't destroy the machinery and the machinery dies for reasons unrelated to the fluid, it "works" (and works for a "lifetime").
This is why the term "lifetime fluid" is so dumb.
What's "lifetime" mean?
If a new Mercedes gets totaled leaving the dealership? I guess so.
A 1993 Toyota PU 22RE with 450K mikes and running great? I guess not?
I think that Methusala cat lived 900 years or something?
What's "lifetime" mean?
If a new Mercedes gets totaled leaving the dealership? I guess so.
A 1993 Toyota PU 22RE with 450K mikes and running great? I guess not?
I think that Methusala cat lived 900 years or something?
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"Lifetime" fills are a joke. Keeping the transmission fluid changed regularly and the transmission may last forever. Keeping the "lifetime" fluid in it, and it may die within 100,000 miles.
Originally Posted by aquariuscsm
"Lifetime" fills are a joke. Keeping the transmission fluid changed regularly and the transmission may last forever. Keeping the "lifetime" fluid in it, and it may die within 100,000 miles.
They usually don't. However-all bets are off after about 150,000 miles.
"Lifetime" fills are a joke. Keeping the transmission fluid changed regularly and the transmission may last forever. Keeping the "lifetime" fluid in it, and it may die within 100,000 miles.
They usually don't. However-all bets are off after about 150,000 miles.
In reality, possibly the transmission will be worn out before the fluid is worn out? That makes sense to me. Not all of us want to keep a vehicle for 250,000 miles but, will settle for 150,000. Ed
In this case they mean car's Warranty duration, not owner's lifetime.
Originally Posted by Eddie
In reality, possibly the transmission will be worn out before the fluid is worn out?
The majority of the components in a transmission shouldn't "wear out" if properly lubricated though. A gear that has a tooth that snaps off isn't likely due to lack of lubrication, but a metallurgy flaw. No amount of fluid will avoid that.
In reality, possibly the transmission will be worn out before the fluid is worn out?
The majority of the components in a transmission shouldn't "wear out" if properly lubricated though. A gear that has a tooth that snaps off isn't likely due to lack of lubrication, but a metallurgy flaw. No amount of fluid will avoid that.
MolaKule
Staff member
Originally Posted by aquariuscsm
"Lifetime" fills are a joke. Keeping the transmission fluid changed regularly and the transmission may last forever. Keeping the "lifetime" fluid in it, and it may die within 100,000 miles.
A good suggestion.
1. The OP's question is about Lifetime fluid, not the mechanical's.
2. No one ever really defines "Lifetime" fluid. However, the implication is that Lifetime is the period from zero miles to the cessation of the warranty, then all bets are off.
3.
Originally Posted by Bill_W
Then they say suggested service interval at specific time/mileage in the Operator's Manual.
Right. If it is lifetime fluid, why is there a suggested service interval if the fluid is truly Lifetime? Could the Mechanical engineers have consulted the Lubrication engineers and through tests have determined that fluid degradation can actually reduce efficiency and increase wear?
I wish we could formulate a truly Lifetime fluid but we are not there yet for the reasons I described above in post #5456764. The real world is that we can't and any lubrication chemist who has even minimal education in this field would know that.
"Lifetime" fills are a joke. Keeping the transmission fluid changed regularly and the transmission may last forever. Keeping the "lifetime" fluid in it, and it may die within 100,000 miles.
A good suggestion.
1. The OP's question is about Lifetime fluid, not the mechanical's.
2. No one ever really defines "Lifetime" fluid. However, the implication is that Lifetime is the period from zero miles to the cessation of the warranty, then all bets are off.
3.
Originally Posted by Bill_W
Then they say suggested service interval at specific time/mileage in the Operator's Manual.
Right. If it is lifetime fluid, why is there a suggested service interval if the fluid is truly Lifetime? Could the Mechanical engineers have consulted the Lubrication engineers and through tests have determined that fluid degradation can actually reduce efficiency and increase wear?
I wish we could formulate a truly Lifetime fluid but we are not there yet for the reasons I described above in post #5456764. The real world is that we can't and any lubrication chemist who has even minimal education in this field would know that.
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Originally Posted by MolaKule
Originally Posted by aquariuscsm
"Lifetime" fills are a joke. Keeping the transmission fluid changed regularly and the transmission may last forever. Keeping the "lifetime" fluid in it, and it may die within 100,000 miles.
A good suggestion.
1. The OP's question is about Lifetime fluid, not the mechanical's.
2. No one ever really defines "Lifetime" fluid. However, the implication is that Lifetime is the period from zero miles to the cessation of the warranty, then all bets are off.
3.
Originally Posted by Bill_W
Then they say suggested service interval at specific time/mileage in the Operator's Manual.
Right. If it is lifetime fluid, why is there a suggested service interval if the fluid is truly Lifetime? Could the Mechanical engineers have consulted the Lubrication engineers and through tests have determined that fluid degradation can actually reduce efficiency and increase wear?
I wish we could formulate a truly Lifetime fluid but we are not there yet for the reasons I described above in post #5456764. The real world is that we can't and any lubrication chemist who as even minimal education in this field would know that.
Spot on!
I have far less knowledge of oils than many folks around here, but have a fair amount of knowledge of marketing (and some anecdotal first-hand evidence for which things do not work as advertised). I don't think any lubrication chemist (or anyone with "common" sense) is deceived by the claims of a lifetime fluid. The problem is that sense is not particularly common, and a small percentage of people are lubrication chemists. The rest of the population is therefore susceptible to marketing claims. Admittedly I am influenced to a certain degree by these claims, but I like to think that I have the wherewithal to wade through the BS before jumping on the latest product. This does not mean I have never bought into the BS, but I am happiest when these occurrences are rare.
Originally Posted by aquariuscsm
"Lifetime" fills are a joke. Keeping the transmission fluid changed regularly and the transmission may last forever. Keeping the "lifetime" fluid in it, and it may die within 100,000 miles.
A good suggestion.
1. The OP's question is about Lifetime fluid, not the mechanical's.
2. No one ever really defines "Lifetime" fluid. However, the implication is that Lifetime is the period from zero miles to the cessation of the warranty, then all bets are off.
3.
Originally Posted by Bill_W
Then they say suggested service interval at specific time/mileage in the Operator's Manual.
Right. If it is lifetime fluid, why is there a suggested service interval if the fluid is truly Lifetime? Could the Mechanical engineers have consulted the Lubrication engineers and through tests have determined that fluid degradation can actually reduce efficiency and increase wear?
I wish we could formulate a truly Lifetime fluid but we are not there yet for the reasons I described above in post #5456764. The real world is that we can't and any lubrication chemist who as even minimal education in this field would know that.
Spot on!
I have far less knowledge of oils than many folks around here, but have a fair amount of knowledge of marketing (and some anecdotal first-hand evidence for which things do not work as advertised). I don't think any lubrication chemist (or anyone with "common" sense) is deceived by the claims of a lifetime fluid. The problem is that sense is not particularly common, and a small percentage of people are lubrication chemists. The rest of the population is therefore susceptible to marketing claims. Admittedly I am influenced to a certain degree by these claims, but I like to think that I have the wherewithal to wade through the BS before jumping on the latest product. This does not mean I have never bought into the BS, but I am happiest when these occurrences are rare.
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Originally Posted by MolaKule
Sealed or not sealed, the Visual condition of a fluid tells you nothing about its remaining chemical condition.
True. But, over hundreds of thousands of mile across multiple vehicles I had never seen fluid that looked and smelled so clean it was noteworthy. It's not outside the realm of possibility that some units are easier on fluid or some fluids are better than others.
Sealed or not sealed, the Visual condition of a fluid tells you nothing about its remaining chemical condition.
True. But, over hundreds of thousands of mile across multiple vehicles I had never seen fluid that looked and smelled so clean it was noteworthy. It's not outside the realm of possibility that some units are easier on fluid or some fluids are better than others.
I tend to agree. ^^^^^
The CVT fluid in my car was so clear and clean when I first checked it I could hardly see it at all on the stick. And it stated that way from 40,000 all the way up until 120,000+ miles. Even then it was still hard to see. The CVT fluid did start to have more color after 200,000 miles. By the time I changed it at 283,500 miles it had the same color as motor oil with 2,000 miles on it. With the 4 drain and refills I have done on my car the CVT fluid is now back to where I can't hardly see it again.
The color change was likely due to oxidation of the CVT fluids many, many miles and heat cycles pit on it. The vast majority of the miles on my car have been cruising at highway speeds 64-79 mph. That obviously helped keep the overall fluid temperature down a fair amount. Eventually the heat that it was being put through caused the subtle yet steady change in it's appearance.
What prompted me to change the CVT fluid was the noticeable noise increase especially at cooler temps after start up in September. After the first 3 drain and refills it was way, way quieter than it was before. I knew with winter coming it would be best to change it out before it got really cold.
I do agree with Dr. Molakule that we cannot know the true state aka viscosity, any wear metals present or depletion of the additives, or the TBN or TAN of the CVT fluid just by observation with our eyes.
I do believe that when fluid color does change it is worth paying attention to. And especially if the fluid color changes rapidly... A slow very subtle change is not a unexpected finding. And yes, it is not truly definitive way to assess a fluid's viability or how much life could be left in it. Obviously lab analysis is needed for a definitive answer to that.
My car does have the internal ECM function where it will let you know when the fluid needs to be changed by the deterioration date of 210,000... Obviously it's not set by miles because I went well beyond that
In all my reading up on this system it became quite clear that those people who had their vehicles scanned by the Consult tool their deterioration numbers were actually quite low. The highest one I saw one guy who's number was 56,000 in just 66,000 miles of driving. Most other results were well, well less than that.
The CVT fluid in my car was so clear and clean when I first checked it I could hardly see it at all on the stick. And it stated that way from 40,000 all the way up until 120,000+ miles. Even then it was still hard to see. The CVT fluid did start to have more color after 200,000 miles. By the time I changed it at 283,500 miles it had the same color as motor oil with 2,000 miles on it. With the 4 drain and refills I have done on my car the CVT fluid is now back to where I can't hardly see it again.
The color change was likely due to oxidation of the CVT fluids many, many miles and heat cycles pit on it. The vast majority of the miles on my car have been cruising at highway speeds 64-79 mph. That obviously helped keep the overall fluid temperature down a fair amount. Eventually the heat that it was being put through caused the subtle yet steady change in it's appearance.
What prompted me to change the CVT fluid was the noticeable noise increase especially at cooler temps after start up in September. After the first 3 drain and refills it was way, way quieter than it was before. I knew with winter coming it would be best to change it out before it got really cold.
I do agree with Dr. Molakule that we cannot know the true state aka viscosity, any wear metals present or depletion of the additives, or the TBN or TAN of the CVT fluid just by observation with our eyes.
I do believe that when fluid color does change it is worth paying attention to. And especially if the fluid color changes rapidly... A slow very subtle change is not a unexpected finding. And yes, it is not truly definitive way to assess a fluid's viability or how much life could be left in it. Obviously lab analysis is needed for a definitive answer to that.
My car does have the internal ECM function where it will let you know when the fluid needs to be changed by the deterioration date of 210,000... Obviously it's not set by miles because I went well beyond that
In all my reading up on this system it became quite clear that those people who had their vehicles scanned by the Consult tool their deterioration numbers were actually quite low. The highest one I saw one guy who's number was 56,000 in just 66,000 miles of driving. Most other results were well, well less than that.
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