Honda ATF DW-1 vs Castrol Transmax import

Honda has been making their own automatic transmissions since the 1970s. The reason they use the design they use is because of patent issues with planetary geared transmissions. Long before Z1 and the upscale shift. They used Dexron in their transmissions until 2000 when they created Z1. Another decade later, they started using DW1.

The new 10-speed automatic they just released does use planetary gears like most automatics, making it Honda's first in-house planetary gear automatic transmission (they also use the ZF9 on some cars)
You're right, I totally forgot the part about planetaries when I was typing that.

Of course, prior to the early 2000's, they were also 3 and 4 speed units. Probably a great bit easier to get the shift timings down on those. The 5 speed is where they really started to run into issues with shift quality, although the 99-02 I4 transmission certainly had its fair share of problems and it was only a 4 speed.
 
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You would think that Idemitsu, who probably knows exactly how the sauce is made would use it if they needed to in order to offer a 'suitable for' DW1 mix.
Pretty simple explanation (well, a guess on my part) here, presuming Idemitsu does in fact blend genuine Honda ATF - contract says they can't copy it.
 
Pretty simple explanation (well, a guess on my part) here, presuming Idemitsu does in fact blend genuine Honda ATF - contract says they can't copy it.

Probably, but it wouldn't stop the other people (Aisin mostly) from completely knocking it off and doing it. They would be under no such contract. My guess is you can accomplish the same thing in different ways is all it is. Perhaps the 'new' way is cheaper or easier to make. Another guess is that Honda could probably change to the 'new' way as well except they've recommended DW1 for everything over the years and there might be a couple of edge cases that need that exact formulation or bad things happen.

Who knows.....lots of speculation. Maybe one day a Honda engineer will show up and all of us will be wrong.
 
without real data we will never know. idemitsu might know the answer and calculated the risks with their aftermarket offering.

if the aftermarket fluid of your choice shifts ok, go for it i guess
 
Probably, but it wouldn't stop the other people (Aisin mostly) from completely knocking it off and doing it. They would be under no such contract. My guess is you can accomplish the same thing in different ways is all it is.
I don't know if doing an analysis is 100% sufficient to "clone" a fluid or not but the other fluid makers can analyze it and reproduce it if they want. Idemitsu, again presuming they blend DW-1 for Honda, is likely forbidden from doing so. Valvoline, Castrol, etc also aren't going to put a whole bunch of those 2-3 components into their "universal" fluids either. What would be interesting if someone like Valvoline, Castrol, etc made a Honda-specific ATF and what they put in it. Probably not worth their effort though...
 
I don't know if doing an analysis is 100% sufficient to "clone" a fluid or not but the other fluid makers can analyze it and reproduce it if they want. Idemitsu, again presuming they blend DW-1 for Honda, is likely forbidden from doing so. Valvoline, Castrol, etc also aren't going to put a whole bunch of those 2-3 components into their "universal" fluids either. What would be interesting if someone like Valvoline, Castrol, etc made a Honda-specific ATF and what they put in it. Probably not worth their effort though...
Besides to be labeled ATF DW-1 it would have to be licensed, and most Asian manufacturer's don't license their requirements.
 
Aisin sells "ATF DW-1", says it's "formulated" for DW-1 applications, and even references a Honda fluid p/n. Beck-Arnley calls theirs "Type DW-1" and also lists the Honda fluid p/n it can replace. Neither refers to any licensing deals. Interestingly, the B-A fluid has "a unique mix of friction materials for the specific pressure settings present in Acura and Honda automatic transmissions which helps promote optimum shift quality".
 
Aisin sells "ATF DW-1", says it's "formulated" for DW-1 applications, and even references a Honda fluid p/n. Beck-Arnley calls theirs "Type DW-1" and also lists the Honda fluid p/n it can replace. Neither refers to any licensing deals. Interestingly, the B-A fluid has "a unique mix of friction materials for the specific pressure settings present in Acura and Honda automatic transmissions which helps promote optimum shift quality".
Yep that's correct. But still not the same as Honda ATF DW-1 as shown through the analysis posted here. Honda does not license that product no matter what someone prints on the label.
 
I'm not an expert on ATF, but I use Honda DW-1 (part #08200-9008A) on my 2015 Acura MDX, paid $5.94/qt(today's price at oemacuraparts.com) plus shipping.

Whenever I need some OEM parts, I order a case(12qt) of DW-1 as well, that way the total shipping cost is just around $20, depending on your location and what I buy. Even with shipping cost, it's usually $8-9 per qt or less. I don't want to lose one minute of sleep on a few dollars.
 
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I'm not an expert on ATF, but I use Honda DW-1 (part #08200-9008A) on my 2015 Acura MDX, paid $5.94/qt(today's price at oemacuraparts.com) plus shipping.

Whenever I need some OEM parts, I order a case(12qt) of DW-1 as well, that way the total shipping cost is just around $20, depending on your location and what I buy. Even with shipping cost, it's usually $8-9 per qt or less. I don't want to lose one minute of sleep on a few dollars.
FWIW when I was using Honda DW-1 my local dealer gave me a decent discount when I purchased a whole case.
 
I don't think I have heard of a blown up Honda automatic transmission from putting MaxLife in it.
Well, I now have several hundred thousand miles between two Hondas using ML since Z1 discontinued. (btw, 'in my observation' latter on of the most complained about ATFs this subforum). Both Hondas are considered by some to be problematic ATs, 01 Civic and a V6. The former is (or was) actually #1 in car complaints. This with only 25-30k mile simple single d&fs, ~3qts. For $18/gal WM price, it's worked for me.

Anecdotal evidence no doubt, but I've been satisfied.

And as noted here and pinned this subforum, 'none' of the aftermarket Z1/DW1 alternatives have the same elemental analysis as the OEM. That despite 'imo' deceptive labeling by some. I think what it does show though at least for topic Honda, more than one way to skin a cat.
 
I have been using Valvoline Maxlife in my Honda vehicIes for a long time with good results. Is Castrol Transmax Import synthetic ?
 
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I have been using Valvoline Maxlife in my Honda vehicIes for a long time with good results. Is Castrol Transmax Import synthetic ?

Transmax Import is not synthetic, but Castrol does make a full synthetic ATF that is very good and a great choice for Hondas :)
 
I have been using Valvoline Maxlife in my Honda vehicIes for a long time with good results. Is Castrol Transmax Import synthetic ?
slacktide already responded but Castrol's IMV ATF has been around for a few years, before synthetic ATFs were as common. Later on, Castrol developed a synthetic version of their ATF. It seemed to consolidate the applications that are covered into a single ATF formulation. Don't hold me to this 100%, but every application that Transmax IMV worked for also works for the new synthetic fluid.
 
I've having a negative experience with Maxlife in my honda DW1 application. Harsh or jerky downshifts in low gear. I hopefully will try to get a dw1 deal for a case or the idetimitsu equivalent which I don't know the model number
 
While a number of people have no issues with the Idemitsu ATF, it is NOT "equivalent" to Honda DW-1. In your situation, I'd play it safe and only use genuine Honda DW-1 and do (2) drain and refills minimum.
 
I've having a negative experience with Maxlife in my honda DW1 application. Harsh or jerky downshifts in low gear. I hopefully will try to get a dw1 deal for a case or the idetimitsu equivalent which I don't know the model number
I've read in Honda forums, that the Maxlife is a popular alternative but you get harsher shifts. I'm in Canada and AFAIK, the DW-1 is full synthetic in Canada, but not in the USA. I only buy DW-1 because of peace of mind - I won't wonder if the alternative is sufficient or not - but, ****, pretty expensive here. I bought some used bottles that are really old and only realized that after I looked closely at them. I read some posts here asking about old (one guy had 10 year-old fluids) bottles - DW-1 was apparently first used in 2011, so that I have can't be more than 10 years old? :)

You could call up the Honda dealership and see what they say about other fluids - they will recommend DW-1 but see what they say if you said, if there was no other choice...or ask what they think about Maxlife - do they have any customers who use that one?
 
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