Honda DW-1 VOA

[bulwnkl]

There was some discussion in this sub-forum two or three months ago as to whether Honda's DW-1 (_NOT_ the clones, the actual Honda-branded fluid) is formulated with little to no phosphorus. See here.

So, I decided to run a VOA on some I bought from my local Honda dealer from whom I buy lots of stuff. Here's what I got:

Fe: 0
Cr: 0
Pb: 0
Sn: 0
Al: 0
Ni: 0
Ag: 0
Si: 3
K: 1
Na: 1
B: 278
Mg: 228
Ca: 376
Ba: 0
Zn: 361
Mo: 0
Ti: 0
V: 1

Visc (100C): 7.5 cSt

As we see, this is _not_ a zero-phos formulation. At the same time, it is certainly a very low-phos formulation. This is in apparent contrast to pretty well all contemporary ATFs intended for use in new-design (step-shift) A/Ts.

I'd be curious for the thoughts of the formulators here as to what Honda's goals might be here.

 

[SubieRubyRoo]

How exactly can I see this is not a zero-phosphorous formulation? P is not even reported in your VOA?

 

[MolaKule]

If you can post the full analysis as a picture from say a scan we could analyze it.

Something isn't quite right with the numbers.

 

[bulwnkl]

That's odd. P = 11
I don't have an image host at present. I'll see about getting something set up.

 

[ctechbob]

Originally Posted by bulwnkl
That's odd. P = 11
I don't have an image host at present. I'll see about getting something set up.


You can upload it to the forum and it will be hosted here.

 

[bulwnkl]

Okay, here's an image of the VOA. Molakule or another moderator, how about inserting this into post 1?

 

[MolaKule]

What type of transmission design is this fluid targeted?

Any exploded views of the transmissions that specs this fluid?

It looks more like a dual-clutch or an automated manual transmission fluid.

 

[ctechbob]

Honda used the DW1 to cover most all of its 2000-Current 4/5 speed autos. Generally all torque converter autos. I know they've used some 'unique' designs over the years more akin to an aromatically shifted manual, but I'm not knowledgeable enough to know what all the differences were over the years.

 

[ctechbob]

From memory, and I could be 100% completely wrong, Honda didn't use planetaries or bands in most of their stuff. Just clutch packs to engage the different ratios.

 

[bulwnkl]

Originally Posted by MolaKule
What type of transmission design is this fluid targeted?

Any exploded views of the transmissions that specs this fluid?

It looks more like a dual-clutch or an automated manual transmission fluid.



I'm afraid I don't have any exploded or cutaway drawings. It is the ATF Honda specs for all their torque converter A/Ts for a very long time. It replaced Z-1 ATF, and is back-spec'd for all the older Honda A/Ts which spec'd Z-1, as far as I know.

I've often read that Honda A/Ts are of a bit different design than most. I do not know, having never disassembled one. I've read that they're somehow more like a manual transmission internally vs. the planetary systems of most A/Ts, but again I do not know for certain.

 

[bulwnkl]

Sorry, ctechbob, I didn't refresh the page so I didn't see your last post.

 

[ctechbob]

Found one. This should be of the '3 Shaft' transmission they used in their V6 Accords in the mid 2000's. Should be typical of their design during that time frame.

 

[PandaBear]

Yup, shifted manual like design with 2 shafts, replace the synchros with clutch packs.

Zinc in the fluid, lots of detergent like B, Mg, and Ca. I've heard people said Zinc will plug up of a paper clutch pack material and I've also heard people complaining about Honda shift harsh with normal fluid, and a "highly friction modified fluid like Maxlife and Castrol Import Multi" works on Honda. So it seems like they are using Zinc to soften up the harsh shift and any ATF that can do this will work too?

Whatever you use don't put the Honda ATF (Z or DW1) into other cars.

 

[kschachn]

Originally Posted by PandaBear
Whatever you use don't put the Honda ATF (Z or DW1) into other cars.

Man if that were true wouldn't you think Honda would put a big warning statement on the container?

 

[PandaBear]

Originally Posted by kschachn
Originally Posted by PandaBear
Whatever you use don't put the Honda ATF (Z or DW1) into other cars.

Man if that were true wouldn't you think Honda would put a big warning statement on the container?


It is not Honda's fault if you use their ATF in a Ford or GM. Ford or GM would probably warn you about not putting non approved non spec fluid in their cars.

 

[bulwnkl]

Someone on the board here, I really thought it was Molakule, but I don't have a link to the thread... anyway,

Someone said a few years ago (speaking of Z-1, this fluid's higher-vis predecessor) that other ATFs could work perhaps well in place of Honda's fluid, but that Honda's fluid should _not_ be used in place of other AFTs.

 

[ctechbob]

I talked to the well regarded Honda transmission guy that did the rebuild for my wife's 2000 about fluid. He's pretty much of the opinion that a good multi use fluid will do just fine in them and that's exactly what he uses in his shop/rebuilds (Wish I'd snapped a picture of the drum last time I was up there). I'm pretty much sticking with the Idemitsu stuff for now in my V6's, and the wife's rebuild is going back to Maxlife the next time I change it. I don't expect any problems out of any of them that will have been caused by fluid.

 

[MolaKule]

Originally Posted by PandaBear
Yup, shifted manual like design with 2 shafts, replace the synchros with clutch packs.

Zinc in the fluid, lots of detergent like B, Mg, and Ca. I've heard people said Zinc will plug up of a paper clutch pack material and I've also heard people complaining about Honda shift harsh with normal fluid, and a "highly friction modified fluid like Maxlife and Castrol Import Multi" works on Honda. So it seems like they are using Zinc to soften up the harsh shift and any ATF that can do this will work too?

Whatever you use don't put the Honda ATF (Z or DW1) into other cars.



For sure and that is what I suspected. I doubt their clutch packs are typical of the wet clutch packs used in the more typical Western full-auto designs.

The Magnesium, and Calcium are acting as the friction modifiers in this fluid, typical of the automated manuals.

i would have expected the Phos to be 300ppm+ and the zinc to be 11 ppm, where usually the phos is the main AW component, but if this is accurate, apparently they are not using ZDDP but a zinc ester.

The 11 ppm of phos must be coming from the phosphorylated Boron compound, another AW component.

 

[ctechbob]

Interesting that they didn't appear to change the additives much from the old Z1. Granted, I'm sure there's more to it than meets the eye with the base stocks/etc.

ATF Z1 VOA

 

[PandaBear]

They back spec DW1 to Z1 and obsolete Z1 completely. You won't want to retest everything under the sun if you can avoid it.