How important is the VI for ATF?
- Thread starter Capa
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Absolutely. A modern auto trans is a VERY sophisticated machine.
Yes, because the VI is still a measure of how resistant to viscosity changes the ATF is.
Thanks for the replies, guys. So it seems that viscocity index is important for ATF.
I was looking at some synthetic ATF for my Lexus, which calls for Toyota IV. A lot of the ATFs I've looked at have an ok to great viscosity index. For example, Valvoline Maxlife 169, Amsoil 163, Mobil 3309 180, and Castrol Import Multi-Vehicle 200. I'm sure I've missed some other synthetic ATFs but would love to hear some suggestions from you all. Thanks.
I was looking at some synthetic ATF for my Lexus, which calls for Toyota IV. A lot of the ATFs I've looked at have an ok to great viscosity index. For example, Valvoline Maxlife 169, Amsoil 163, Mobil 3309 180, and Castrol Import Multi-Vehicle 200. I'm sure I've missed some other synthetic ATFs but would love to hear some suggestions from you all. Thanks.
Go with the Amsoil.
Originally Posted By: Donald
Go with the Amsoil.
Why?
Go with the Amsoil.
Why?
Help me choose the ATF to replace Toyota IV:
Amsoil
Viscosity index: 163
KV @ 100 C: 7.5
KV @ 40 C: 38.8
Castrol Import Multi-Vehicle
Viscosity index: 200
KV @ 100 C: 8
KV @ 40 C: 36.6
Valvoline Maxlife
Viscosity index: 173
KV @ 100 C: 6.11
KV @ 40 C: 28.18
Mobil
Viscosity index: 180
KV @ 100 C: 7.2
KV @ 40 C: 35
The Valvoline seems very thin---should I worry if I go this route? I like Castrol's numbers but is it a little too thick?
Amsoil
Viscosity index: 163
KV @ 100 C: 7.5
KV @ 40 C: 38.8
Castrol Import Multi-Vehicle
Viscosity index: 200
KV @ 100 C: 8
KV @ 40 C: 36.6
Valvoline Maxlife
Viscosity index: 173
KV @ 100 C: 6.11
KV @ 40 C: 28.18
Mobil
Viscosity index: 180
KV @ 100 C: 7.2
KV @ 40 C: 35
The Valvoline seems very thin---should I worry if I go this route? I like Castrol's numbers but is it a little too thick?
Originally Posted By: Capa
Help me choose the ATF to replace Toyota IV:
Personally I'd use Red Line D6, but I'd do a quick fluid change with a cheap replacement first to help clean out the junk first. I'd also do a pan-drop & filter clean / swap if applicable and throw some magnets in the pan while you're at it.
http://www.redlineoil.com/content/files/tech/ATF PDS 1-10.pdf
Help me choose the ATF to replace Toyota IV:
Personally I'd use Red Line D6, but I'd do a quick fluid change with a cheap replacement first to help clean out the junk first. I'd also do a pan-drop & filter clean / swap if applicable and throw some magnets in the pan while you're at it.
http://www.redlineoil.com/content/files/tech/ATF PDS 1-10.pdf
Redline D6 isn't recommended for my car (1999 Lexus GS400). You must mean Redline D4, and its stats are very good but it probably would be the most expensive of the ATFs that I have mentioned:
Redline D4
Viscosity index: 198
KV @ 100 C: 7.5
KV @ 40 C: 34
Redline D4
Viscosity index: 198
KV @ 100 C: 7.5
KV @ 40 C: 34
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Originally Posted By: Capa
The question is simple: is an ATF's viscocity index as important as it is in engine oil?
It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
The question is simple: is an ATF's viscocity index as important as it is in engine oil?
It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
Originally Posted By: Whitewolf
Originally Posted By: Capa
The question is simple: is an ATF's viscocity index as important as it is in engine oil?
It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
Indeed. VI alone means very, very little.
Originally Posted By: Capa
The question is simple: is an ATF's viscocity index as important as it is in engine oil?
It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
Indeed. VI alone means very, very little.
MolaKule
Staff member
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It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
Absolutely.
If I start off with a mineral oil of low VI and add oodles (technical word for "lots") of VII's, I can end up with a high resultant VI of 200.
But if I start with a high visosity index PAO or ester (or mix of the two), I can add very little VII to get a VI of 190.
It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
Absolutely.
If I start off with a mineral oil of low VI and add oodles (technical word for "lots") of VII's, I can end up with a high resultant VI of 200.
But if I start with a high visosity index PAO or ester (or mix of the two), I can add very little VII to get a VI of 190.
Originally Posted By: Whitewolf
It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
Is it the same way with engine oils? And, if it isn't important unless we know how the ATF is formulated, then how can a consumer measure the ATF product? What spec can I use that will tell me about the ATF's performance?
It is not important at all unless you know how the fluid was formulated and therefore how the VI 'number' was achieved.
Is it the same way with engine oils? And, if it isn't important unless we know how the ATF is formulated, then how can a consumer measure the ATF product? What spec can I use that will tell me about the ATF's performance?
Originally Posted By: Whitewolf
Simple. Only use licenced products and look for the licence number verification on the packaging. The specifications that go with the licence are public information and are available.
If I only use officially licensed products, wouldn't that eliminate all of the boutique ATFs as well as "universal" ATFs?
And since Toyota/Lexus don't make their ATF but it is apparently just a rebadged Mobil ATF, you are saying to either go with Toyota IV or Mobil (since they are licensed). The problem is that i was wanting to go with a synthetic ATF.
Simple. Only use licenced products and look for the licence number verification on the packaging. The specifications that go with the licence are public information and are available.
If I only use officially licensed products, wouldn't that eliminate all of the boutique ATFs as well as "universal" ATFs?
And since Toyota/Lexus don't make their ATF but it is apparently just a rebadged Mobil ATF, you are saying to either go with Toyota IV or Mobil (since they are licensed). The problem is that i was wanting to go with a synthetic ATF.
Originally Posted By: Capa
Redline D6 isn't recommended for my car (1999 Lexus GS400). You must mean Redline D4...
No, I would stick with D6 as it's superior to any Dexron III type fluid due to it being a shear-stable 6.1 cSt fluid. It should be much more than adequate for any application that used a Dexron III similar fluid.
So yes, if it was me I'd go with the Red Line D6 and some improved filtering. More research might be in order for this application though.
Are you stressing the fluid or transmission? Racing?
Redline D6 isn't recommended for my car (1999 Lexus GS400). You must mean Redline D4...
No, I would stick with D6 as it's superior to any Dexron III type fluid due to it being a shear-stable 6.1 cSt fluid. It should be much more than adequate for any application that used a Dexron III similar fluid.
So yes, if it was me I'd go with the Red Line D6 and some improved filtering. More research might be in order for this application though.
Are you stressing the fluid or transmission? Racing?
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Redline's D4 is said to satisfy Toyota's IV spec; Redline D6 doesn't. If I am going to run a universal ATF, it must at least satisfy Toyota's spec. Plus the D4's viscocity index is much better and it seems that the D6 might be too thin for my tastes.
Redline D6
Viscosity: 166
KV @ 100C: 6.4
KV @ 40 C: 30.7
Again, the only way I will run a universal ATF is if it at least claims to meet the Toyota IV spec, which D6 doesn't claim.
Redline D6
Viscosity: 166
KV @ 100C: 6.4
KV @ 40 C: 30.7
Again, the only way I will run a universal ATF is if it at least claims to meet the Toyota IV spec, which D6 doesn't claim.
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