I've heard all the arguments for always sticking with OEM ATF. My original plan was to use Amsoil motor oil, crank, and transfer case oil but stick with Toyota WS ATF in my 08 Land Cruiser because transmissions are very picky and ATF is designed specifically for specific transmissions and all that. Then I started reading on Amsoil vs WS, checking forums, and watching some pretty compelling videos.
Specifically, this one, demonstrating that Amsoil will flow much better than WS in super low temps (probably not an issue for most people).
Also, this guy, who has several update videos, who seemingly had stellar results. Tons of people in the comments echo this sentiment for all kind of vehicles.
I know you could write these folks off as Amsoil shills, but try as I might, I have yet to find anyone who's had negative experiences ACTUALLY USING Amsoil ATF. All the reviews are stellar, except a few on Amazon not it's priced too high....but all reviews of the product itself are amazing.
You'd think if this stuff was actually so dangerous as the OEM's claim, that you'd have people complaining about it or saying that it caused transmission damage after time. The opposite seems to be the case, with people saying their transmissions shift better/smoother, generate less noise and less heat, and upon changing the fluid it looks as good as new (ie. no metal shavings or heat damage).
Also, Amsoil Signature ATF is full synthetic. Toyota WS is not.
Looking at the actual specs things get a bit more interesting.
Amsoil
Toyota WS
I'm no expert, but the long as short of this appears to be that Amsoil operates better in lower temps (retaining decent viscosity with a lower pour point), while Toyota WS operates better at higher temps (retaining lower viscosity at higher temps than Amsoil). Toyota WS has a "better" overall VI as well. I know there are lots of factors that go into what makes a good ATF for a specific transmission, but this was a bit concerning, so I decided I'd check out some WS alternatives that were specifically formulated for WS applications, and preferably full synthetic (which is general preferable to mineral based oils).
That led to Idemitsu ATF type TLS-LV. It's a fully synthetic ATF that is specifically formulated for WS transmissions. Seems to get great reviews (better than Amsoil and Toyota WS) from the experts at Bob Is The Oil Guy forum (Idemitsu ATF Type TLS-LV (WS) - https://bobistheoilguy.com/forums/threads/idemitsu-atf-type-tls-lv-ws.318645/)
Idemitsu specs:
Viscosities all look very similar to Toyota WS, which is good, pour point is a little lower, and it's full synthetic. This seems like the ideal option. It's a high-quality full synthetic like Amsoil, but specifically formulated for WS transmissions like the Toyota ATF.
Totachi ATF WS is another full synthetic, specifically WS formulated option:
Specs generally look similar to Toyota WS with a much higher flash point than either Toyota WS or Idemitsu. Viscosity index is much lower though, which is a more important spec (generally, lower is worse, higher is better). If your ATF is above 300 degrees F (about 150 C), you've got bigger problems than worrying about flashpoint. Also, higher pour point (bad) and no Brookfield viscosity listed. I think I'll steer clear of this one.
Anyway, this thread is mostly to collect my thoughts, possibly help out other folks who are considering something similar, and of course get the opinions of folks on this forum.
I haven't completely ruled out Amsoil, as a specs sheet doesn't tell the full story, and the anecdotal data from customer experiences seems overwhelmingly good, but I will probably go with the Idemitsu, as it is specifically formulated for WS and appears closest to WS in specs, but it is full synthetic, has a slightly lower pour point and Brookfield viscosity (implying it might be a little better in the cold), yet retains exact same kinematic viscosity at 40C (23) and 100C (5.3). You'd think this would mean it would have a slightly better viscosity index than WS, but for some reason it's a tiny bit lower (175 vs 177). Not sure what that's about. I may clarify this with the experts on bobistheoilguy.
Let me know what you all think or your experiences with different ATF. </novel>
Specifically, this one, demonstrating that Amsoil will flow much better than WS in super low temps (probably not an issue for most people).
Also, this guy, who has several update videos, who seemingly had stellar results. Tons of people in the comments echo this sentiment for all kind of vehicles.
I know you could write these folks off as Amsoil shills, but try as I might, I have yet to find anyone who's had negative experiences ACTUALLY USING Amsoil ATF. All the reviews are stellar, except a few on Amazon not it's priced too high....but all reviews of the product itself are amazing.
You'd think if this stuff was actually so dangerous as the OEM's claim, that you'd have people complaining about it or saying that it caused transmission damage after time. The opposite seems to be the case, with people saying their transmissions shift better/smoother, generate less noise and less heat, and upon changing the fluid it looks as good as new (ie. no metal shavings or heat damage).
Also, Amsoil Signature ATF is full synthetic. Toyota WS is not.
Looking at the actual specs things get a bit more interesting.
Amsoil
Toyota WS
I'm no expert, but the long as short of this appears to be that Amsoil operates better in lower temps (retaining decent viscosity with a lower pour point), while Toyota WS operates better at higher temps (retaining lower viscosity at higher temps than Amsoil). Toyota WS has a "better" overall VI as well. I know there are lots of factors that go into what makes a good ATF for a specific transmission, but this was a bit concerning, so I decided I'd check out some WS alternatives that were specifically formulated for WS applications, and preferably full synthetic (which is general preferable to mineral based oils).
That led to Idemitsu ATF type TLS-LV. It's a fully synthetic ATF that is specifically formulated for WS transmissions. Seems to get great reviews (better than Amsoil and Toyota WS) from the experts at Bob Is The Oil Guy forum (Idemitsu ATF Type TLS-LV (WS) - https://bobistheoilguy.com/forums/threads/idemitsu-atf-type-tls-lv-ws.318645/)
Idemitsu specs:
Viscosities all look very similar to Toyota WS, which is good, pour point is a little lower, and it's full synthetic. This seems like the ideal option. It's a high-quality full synthetic like Amsoil, but specifically formulated for WS transmissions like the Toyota ATF.
Totachi ATF WS is another full synthetic, specifically WS formulated option:
Specs generally look similar to Toyota WS with a much higher flash point than either Toyota WS or Idemitsu. Viscosity index is much lower though, which is a more important spec (generally, lower is worse, higher is better). If your ATF is above 300 degrees F (about 150 C), you've got bigger problems than worrying about flashpoint. Also, higher pour point (bad) and no Brookfield viscosity listed. I think I'll steer clear of this one.
Anyway, this thread is mostly to collect my thoughts, possibly help out other folks who are considering something similar, and of course get the opinions of folks on this forum.
I haven't completely ruled out Amsoil, as a specs sheet doesn't tell the full story, and the anecdotal data from customer experiences seems overwhelmingly good, but I will probably go with the Idemitsu, as it is specifically formulated for WS and appears closest to WS in specs, but it is full synthetic, has a slightly lower pour point and Brookfield viscosity (implying it might be a little better in the cold), yet retains exact same kinematic viscosity at 40C (23) and 100C (5.3). You'd think this would mean it would have a slightly better viscosity index than WS, but for some reason it's a tiny bit lower (175 vs 177). Not sure what that's about. I may clarify this with the experts on bobistheoilguy.
Let me know what you all think or your experiences with different ATF. </novel>
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