Amsoil versus Honda Z1 viscosity question

[Lyondellic]

Amsoil Universal ATF has a viscosity of 6.8 @ 100°C. Amsoil ATD has a viscosity of 7.4 @ 100°C. I am assuming that 100°C is well above the typical operating temperature of these fluids in real world use, but am not sure.

Which of these two fluids best matches (Cold & Hot) the viscosity of Honda Z1? I found some information from used oil analysis, but am not really sure how to do an accurate comparison of viscosity.

 

[Pablo]

Originally Posted By: Lyondellic
Amsoil Universal ATF has a viscosity of 6.8 @ 100°C. Amsoil ATD has a viscosity of 7.4 @ 100°C. I am assuming that 100°C is well above the typical operating temperature of these fluids in real world use, but am not sure.

Which of these two fluids best matches (Cold & Hot) the viscosity of Honda Z1? I found some information from used oil analysis, but am not really sure how to do an accurate comparison of viscosity.


ATF in use gets quite warm. Very warm. Z1 is about 7-7.2 IIRC.

 

[harry j]

Pablo, How about a 50/50 mix of ATF and ATD in a '93 Civic?

 

[Pablo]

Originally Posted By: harry j
Pablo, How about a 50/50 mix of ATF and ATD in a '93 Civic?


Go for it!

 

[Lyondellic]

Originally Posted By: Pablo
Originally Posted By: Lyondellic
Amsoil Universal ATF has a viscosity of 6.8 @ 100°C. Amsoil ATD has a viscosity of 7.4 @ 100°C. I am assuming that 100°C is well above the typical operating temperature of these fluids in real world use, but am not sure.

Which of these two fluids best matches (Cold & Hot) the viscosity of Honda Z1? I found some information from used oil analysis, but am not really sure how to do an accurate comparison of viscosity.


Pablo,

ATF in use gets quite warm. Very warm. Z1 is about 7-7.2 IIRC.



Is the 6.8 viscosity of Amsoil's Universal ATF too low then? Would ATD be a closer match to Honda Z1 from a viscosity standpoint only? Also, what affect would low visosity have other than increased wear?

 

[BuickGN]

Originally Posted By: Lyondellic
Originally Posted By: Pablo
Originally Posted By: Lyondellic
Amsoil Universal ATF has a viscosity of 6.8 @ 100°C. Amsoil ATD has a viscosity of 7.4 @ 100°C. I am assuming that 100°C is well above the typical operating temperature of these fluids in real world use, but am not sure.

Which of these two fluids best matches (Cold & Hot) the viscosity of Honda Z1? I found some information from used oil analysis, but am not really sure how to do an accurate comparison of viscosity.


Pablo,

ATF in use gets quite warm. Very warm. Z1 is about 7-7.2 IIRC.



Is the 6.8 viscosity of Amsoil's Universal ATF too low then? Would ATD be a closer match to Honda Z1 from a viscosity standpoint only? Also, what affect would low visosity have other than increased wear?


I've been using the ATD for over 30K in my overpriced Honda and it works fine. I took a sample for a used oil analysis recently but keep forgetting to send it off.

 

[harry j]

Pablo, BuickGN,
I am going for it based on your recommendations. I will try a ATF/ATD mix to begin with to observe the performance and go from there.

 

[harry j]

I wish they had the ATD quart size, oh well, I will just have to save some empty quart bottles then refill.

 

[Lyondellic]

Originally Posted By: BuickGN
Originally Posted By: Lyondellic
Originally Posted By: Pablo
Originally Posted By: Lyondellic
Amsoil Universal ATF has a viscosity of 6.8 @ 100°C. Amsoil ATD has a viscosity of 7.4 @ 100°C. I am assuming that 100°C is well above the typical operating temperature of these fluids in real world use, but am not sure.

Which of these two fluids best matches (Cold & Hot) the viscosity of Honda Z1? I found some information from used oil analysis, but am not really sure how to do an accurate comparison of viscosity.


Pablo,

ATF in use gets quite warm. Very warm. Z1 is about 7-7.2 IIRC.



Is the 6.8 viscosity of Amsoil's Universal ATF too low then? Would ATD be a closer match to Honda Z1 from a viscosity standpoint only? Also, what affect would low visosity have other than increased wear?


I've been using the ATD for over 30K in my overpriced Honda and it works fine. I took a sample for a used oil analysis recently but keep forgetting to send it off.


Does your Acura TL have a 5-Speed automatic transmission? This seems to be the case from the quick Google search I performed. I wonder how similar the 5-Speed Acura TL transmission is to the 5-Speed transmission in my 2007 Civic LX? I bet they are fairly close. I am leaning more and more towards the ATD instead of the Universal ATF offering.

Two Quick Questions:
1)Did your Acura transmission feel notchy with Z1 ATF?
2)Did you notice any difference after converting to ATD?

 

[BuickGN]

Originally Posted By: harry j
Pablo, BuickGN,
I am going for it based on your recommendations. I will try a ATF/ATD mix to begin with to observe the performance and go from there.


I think I should add that since my car basically cuts power during shifts, that might be why I don't have harsh shifts with the ATD. I'm curious to see how it will work in a Honda that does regular full power upshifts.

 

[BuickGN]

Originally Posted By: Lyondellic
Originally Posted By: BuickGN
Originally Posted By: Lyondellic
Originally Posted By: Pablo
Originally Posted By: Lyondellic
Amsoil Universal ATF has a viscosity of 6.8 @ 100°C. Amsoil ATD has a viscosity of 7.4 @ 100°C. I am assuming that 100°C is well above the typical operating temperature of these fluids in real world use, but am not sure.

Which of these two fluids best matches (Cold & Hot) the viscosity of Honda Z1? I found some information from used oil analysis, but am not really sure how to do an accurate comparison of viscosity.


Pablo,

ATF in use gets quite warm. Very warm. Z1 is about 7-7.2 IIRC.



Is the 6.8 viscosity of Amsoil's Universal ATF too low then? Would ATD be a closer match to Honda Z1 from a viscosity standpoint only? Also, what affect would low visosity have other than increased wear?


I've been using the ATD for over 30K in my overpriced Honda and it works fine. I took a sample for a used oil analysis recently but keep forgetting to send it off.


Does your Acura TL have a 5-Speed automatic transmission? This seems to be the case from the quick Google search I performed. I wonder how similar the 5-Speed Acura TL transmission is to the 5-Speed transmission in my 2007 Civic LX? I bet they are fairly close. I am leaning more and more towards the ATD instead of the Universal ATF offering.

Two Quick Questions:
1)Did your Acura transmission feel notchy with Z1 ATF?
2)Did you notice any difference after converting to ATD?


I believe it's the same transmission. I'm sure Critic will chime in on this.

The shifts were slightly crisper, far from harsh. My car seems to adapt or my memory fades but the crispness fades until I reset the computer.

The car felt fine on the Z1 but I didn't like the way it "slides" into gear on the Z1. To me, this equals wear.

The TCC always engages slowly (1-2 seconds to full lock)and I was worried about shudder with a new fluid but it works very nice in this transmission.

I was worried about the extra viscosity affecting it in the cold but it goes into gear (from neutral to drive or reverse) just as fast if not faster than Z1 when cold. I suspect the ATD flows better when cold.

 

[harry j]

Originally Posted By: BuickGN


I think I should add that since my car basically cuts power during shifts, that might be why I don't have harsh shifts with the ATD. I'm curious to see how it will work in a Honda that does regular full power upshifts.


I will keep you up to date for sure.

 

[The Critic]

The starting viscosity alone does not give you the entire picture. Amsoil ATF is much more shear stable than Honda Z1. I think you'll find that after a normal service interval, the end viscosity of Amsoil ATF will be equal or higher than Honda ATF-Z1.

 

[Lyondellic]

Originally Posted By: The Critic
The starting viscosity alone does not give you the entire picture. Amsoil ATF is much more shear stable than Honda Z1. I think you'll find that after a normal service interval, the end viscosity of Amsoil ATF will be equal or higher than Honda ATF-Z1.


That's an interesting point. Most of us, myself included, cannot know for certain why Amsoil opted for a viscosity of 6.8 @ 100°F for their Universal ATF. This is really the only thing that jumps out at me when comparing it to other ATF offerings. If the Honda Z1 ATF shears, why would Amsoil sell an ATF that already takes shearing into account? That, at least on the surface, doesn't seem to make a lot of sense to me.

 

[Lyondellic]

I just thought of something else. Amsoil developed their ATD fluid for Allison transmissions, but it is spec'd for other service as well. I wonder why Amsoil doesn't develop a Honda Z1 specific fluid in the same manner? Their Universal ATF is close to Honda Z1, but it was not specifically developed to be a Z1 replacement on its own in the same manner that ATD was developed for Allison transmissions. There are a lot of Honda vehicles on the road, so it would make sense for Amsoil to develop a dedicated Z1 replacement fluid IMHO.

 

[Pablo]

For certain Amsoil made a 6.8cSt fluid to come closer to the 6.X of Dexron VI.

Amsoil sells synthetic AT fluids that don't shear and don't have VII's. It's a fluid property. Why doesn't that make sense?

I highly doubt Honda even thinks much about Z1 shearing. It's just a fluid property of Group I-II ATF's containing VII's.

 

[Lyondellic]

If the Dex spec is 6.8, or close to it, then that would make sense. I am not in the know about the various specs, but figured that most ATF's landed somewhere between 7.0 and 7.9 @100°C. If I am correct, this would mean that Amsoil is slightly lower than average. Again, if the Dex spec calls for ~6.8, then I am simply showing my ignorance.

 

[Pablo]

Dex VI is 6.4 IIRC - I have the specification.......hold on.....it's 6.4 cSt MAX. Most all the new ATF specs are in the 6's.

 

[Whitewolf]

They are all about 5.9 to 6.0, very tight.

 

[Lyondellic]

Originally Posted By: Whitewolf
They are all about 5.9 to 6.0, very tight.


Relative to the spec, Honda Z1 is fairly viscous then. Amsoil was also heavy relative to the spec before the formula was changed last year. Some ATF's other brands, like RP Max ATF, are in the 7.4 range. This is also true for Redline D4 and Schaeffer's #204S-AT.