ATF Z1 vs ATF DW1

[harley909]

Is ATF DW1 backward compatible with Z1 or does a complete flush have to be done when changing over?
I have a 2003 Pilot EXL and the Dealer sold me DW1 because Z1 is discontinued. Never noticed til I got home and drained the tranny...and the dealer is closed today and cannot get an answer from them.

[humanoid]

From all accounts on the internet, it's not backward compatible. It looks like it's only for 2011+ vehicles.

[RSQ Pilot]

Originally Posted by harley909

Is ATF DW1 backward compatible with Z1 or does a complete flush have to be done when changing over?
I have a 2003 Pilot EXL and the Dealer sold me DW1 because Z1 is discontinued. Never noticed til I got home and drained the tranny...and the dealer is closed today and cannot get an answer from them.

Not sure on compatability but this may have the answer...if only we could open it...

***.in.honda.com/Rjanisis/pubs/SB/B10-020.PDF

***=www

[harley909]

I ended up getting in contact with the Service Manager at the Dealership who told me it is infact 100% compatible. He told me that he got a bulletin from Honda with the ATF DW1 that said this.
He actually called me from home after I dropped into the Dealership today and talked to the Manager, who called him at home....nice.
I filled the Pilot back up with DW1 and it seems to work just fine so far.
Guess I will be the "guinea pig".......

[RSQ Pilot]

Originally Posted by harley909

I ended up getting in contact with the Service Manager at the Dealership who told me it is infact 100% compatible. He told me that he got a bulletin from Honda with the ATF DW1 that said this.
He actually called me from home after I dropped into the Dealership today and talked to the Manager, who called him at home....nice.
I filled the Pilot back up with DW1 and it seems to work just fine so far.
Guess I will be the "guinea pig".......

Great news....from what I was able to find it appears to be a synthetic (blend??) ATF to replace Z-1 but the shop bulletin has the straight info.

[98RACE]

Just picked up the same stuff for my 08 and was told a flush is not required.

Dave

[whizmo]

Posted on another forum was the actual text of the TSB from Honda....

A new ATF will be available for 2011 models in mid-July. Honda ATF DW-1 is the new transmission fluid that helps improve low temperature performance. Initial shipments will be arriving at your dealership soon. Please begin using ATF DW-1 on all 2011 AT models. For AT models 2010 and older, you can continue using Honda ATF-Z1. Future communications will be sent regarding the supply of ATF-Z1 and ATF DW-1.

In typical fashion for double-speak TSB's, it doesn't answer the pregnant question of whether DW-1 can be used on 2010's and earlier. I suspect it can, but it doesn't say so.

- Mark

[harley909]

I was told point blank by the Honda Dealer that ATF Z1 is discontinued..period. No longer for sale, cannot be bought by the dealer. All that may be left is old stock.
I have done a change using DW-1 without flushing and made a 2400KM round trip (highway and mountains) and have not had any problems. I have a 2003 with 235,000KM on it. My Pilot has the tranny whine but shifts and works perfectly and the fluid stays nice and clean between changes.
I noticed no difference using the DW-1.
When I questioned the Dealer, they told me they have a "Bulletin" which says that Z1 and DW1 are fully compatible and can be interchanged without a flush. I never got a copy from them, but the Service manager called the Honda Tech People and they confirmed it..

[carguy07]

The thing that I have heard is that the new stuff is thinner. Anyone able to confirm that? I question whether this is an improved ATF or just thinner to get better gas mileage ala 5w-20.

[whizmo]

Originally Posted by harley909

I was told point blank by the Honda Dealer that ATF Z1 is discontinued..period. No longer for sale, cannot be bought by the dealer. All that may be left is old stock.
I have done a change using DW-1 without flushing and made a 2400KM round trip (highway and mountains) and have not had any problems. I have a 2003 with 235,000KM on it. My Pilot has the tranny whine but shifts and works perfectly and the fluid stays nice and clean between changes.
I noticed no difference using the DW-1.
When I questioned the Dealer, they told me they have a "Bulletin" which says that Z1 and DW1 are fully compatible and can be interchanged without a flush. I never got a copy from them, but the Service manager called the Honda Tech People and they confirmed it..

This all may be true.... but it may not be either. Dealers say the damnest things sometimes. I've had them flat-out tell me bald-faced lies, or spout as gospel some crap story they heard fourth-hand. Mostly they say what will cause whatever they have in stock to go out the door.

OTOH, it may be that corp Honda is deliberately being vague about backwards-compatability so they can exhaust existing stocks of Z1.

Yes, I'm a skeptical cuss.

- Mark

[harley909]

I can tell you that my comments are true.
I cannot 100% verify that what the Dealer was telling me was 100% true. After all they did not give me the so called "bulletin" which I should have insisted on seeing. I do have a voicemail that I have kept about it when they called me

[whizmo]

Originally Posted by harley909

I can tell you that my comments are true.

Don't get me wrong; I'm not doubting your word. I'm just saying that dealers often get it wrong or simply say what they need to say to get the customer out of their hair and on their way. How many times have we heard the story of folks coming in with major/common issues on their cars and being told that the problem was "normal" or "never heard of". There are some really good people working in car dealerships, but they're outnumbered.

And in this case, I think the dealers may be hamstrung in giving customers definitive guidance by (perhaps deliberately) vague wording in the bulletin.

- Mark

[J Izenhower]

ATF DW-1 is now the recommended fill for ALL Honda automatic tranmisssions, current and past. Z1 is being replaced entirely by DW-1. There has been no service bulletin as rumored as of yet but the information is contained in the 2011 Odyssey technical information training module.

[samc]

We believe you Harley909. It's not that we think you're lying, but those stealerships.

Perhaps Tim can come on and verify the two fluids?

I'd just hate to see people down the line with transmission problems because they started using this DW1 fluid. But I myself would like to see a service bulletin/pdf.

[hondacuraplanet]

For what it's worth, I can't find a bulletin directly on the DW1.

But, I can tell you this. The Z1 fluid is not discontinued at this point in time, therefore personally until I hear otherwise, I'd stick with the Z1.