The switch from Honda ATF Z1 to DW-1.... issues.

Status
Not open for further replies.
Joined
Aug 16, 2011
Messages
15
Location
Toronto, Ontario
Ok.. so I know DW1 vs Z1 has been discussed a number of times on here.. but I wanted to tell my story.. and see if anyone can help.

2005 Acura TSX 5AT with Z1 from factory. Did a factory drain and fill in 2008 (45k) which was early compared to the 96k recommendation. I then had a tranny failure on my Mazda, so it got me concerned about my Acura.

So I brought her into Acura to do a drain and fill.. by then the Z1 fluid looked pale red in colour.. not black or anything. It was 86,000kms or 41k since last changed. (all KMs not Miles).

After the drain and fill, I noticed the dip stick was about a cm over the full when cold and after highway drives.. about 3cms over the full. I also started to notice hard jerks when I was on and off the throttle..(think of applying the brakes hard when the tranny was making a shift). This usually happened when the tranny was cold and from 1st to 2nd gear.

I brought it back to the dealer and they drained ½ liter of fluid (now a mix of Z1 & DW1). On the highway the next day I downshifted using the sportshift and it banged hard into gear. I brought it back to Acura and told them to do another drain and fill… because the fluid must have got aerated from being over-full. (approx 6L DW-1 and 3L Z1)

The car no longer banged hard into gear.. but it also was slowly turning from Winter to Spring.. and the tranny fluid was much warmer… it’s been about 7 months with the DW1 in the tranny.. and it was almost back to normal minus the occasional sharp shifts that have made driving kind of uncomfortable. It has made me extremely sensitive to transmission shifts in any car.. including our new Toyota.

I went back to have one last tranny drain and fill done.. to completely run DW-1… no real change.. I still feel every shift. The shift points also seem to be different, shifts faster than I would expect for other gears and slower from 1st to 2nd.

I have had the Acura dealer drive the car cold and warm on two difference occasions. They find nothing wrong with the tranny. I’ve spoken with a few transmission shops and they explain that DW-1 is doing what it should and making the shifts harder.

I’m considering going BACK to Z1 just to get the smooth shifts I purchased this car for.. is that a waste of time? I know Z1 has a pretty bad rep, but it worked great in my car.. butter smooth shifts. Use to love driving my car, now I look for every excuse not to drive it.
 
Just to add... I find the car drives best when it has been sitting for a few days. Also drives much better in moderate temps.. anything too hot or too cold and it shifts harder.

The mourning drive into work the car is pretty decent. Drive it home from work after sitting 8 hours it shifts harder. Stop and go traffic is like a nightmare.. so many 1st to 2nd shifts.

On the highway if I'm on and off the gas (say at 100km/h) there is a slight pause or disconnect between the power to the wheels and the gas pedal.
 
Friction modifiers do change the coefficient of friction and affect hydraulic actuation. Z1 is getting harder to find. A firmer shift will make a tranny last longer.
 
I had a 07 Mazda6 with the newer Mazda FNR5 5-speed auto, cold mornings were sluggish for a few miles, things felt like an awkward teen on hotter days...

Switched to this:
http://www.amsoil.com/storefront/atf.aspx

On the COLDEST days the first shift of the day was slow, then perfect thereafter. Hot days became just like any other day, smooth shifts when i wanted them.

Don't do a drain and refill, do a flush, low or no pressure (uses the car's fluid pump to move the fluid). Then unplug the battery so the tcu will relearn from scratch.
 
I've changed 1/3 of my fluid out from Z-1 to the new DW-1 and the shifting has gotten smoother. Maybe it's just due to new fluid. Shifts are almost imperceptable now.

I have read that DW-1 is reported to make shifting firmer in colder temperatures, and the "solution" is to mix in some Z-1. I'm not sure how one is supposed to do that now that Z-1 is discontinued.
 
I have done 2 drain and refills with DW-1 and 04 odyssey shifts great. No Issuer or complaints here.
 
You may have some tranny solenoids getting weak or need an PCU flash update. My 2008 had a factory update reprogramming.
 
The bottom line from a Honda Service Bulletin:


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.

DW-1 is semi-synthetic and backwards compatible.

I have a Honda Accord V-6 2010 and 2006 CRV.

My .02?

I am going to use DW-1
 
Last edited:
I had a post earlier about using the DW-1 just a drain and fill with my brother's Civic. We can both tell it shifts better. Maybe try to change back to Z1. I hope there is no problem because I have heard more good reviews than bad and it has worked fine for us (no miracle) but a difference nontheless.
 
Well unless you hoard some Z1.. all Honda trannies will be on DW-1 if they stick to Honda fluid eventually. I really don't like how it drives. Maybe there can be an unrelated issue... praying for a motor mount issue.. the car also vibrates at 100km/h when on and off the gas... (not tire related).. and vibrates at idle while in gear... maybe related.. maybe not.
 
Originally Posted By: tdpark
That does sound like worn motor mounts and worn motor mounts can affect shifting feel.


I hope. The tranny otherwise shifts pretty clean.. no slip.. no loss in power.. just that I feel everything. Mechanic noticed the vibration and said my motor mount was on the way out.. and to wait for it to get worse to determine which one.. its not a simple tear to look for.. my front mount is vacuum controlled.. so its a sealed liquid mount. My rear mount is also fluid filled.
 
What's the procedure to drain and fill as opposed to a full flush?

Think Valvoline is fine or Amsoil? or Royal Purple?

How much comes out and how much goes in?

DO you have to run through the gears to get air out?

What's the best way to do it or leave it to Honda?

Oh, also...some fluids say Honda Compatible" but not CVR compatible. What is CVR ...I assume it's not the CRV... ignorance IS SHOWING.


Also, do you need a new crush washer every time you drain and re-install the plug?
 
Last edited:
Originally Posted By: 229
You may have some tranny solenoids getting weak or need an PCU flash update. My 2008 had a factory update reprogramming.


Good suggestion with the re-flash.

Go back to the dealer and check for any re-flashes. If none are available, have them re-set the adaptives for the transmission and drive as you normally would after, so it can re-learn your driving habits.
 
Originally Posted By: The_Eric
Originally Posted By: 229
You may have some tranny solenoids getting weak or need an PCU flash update. My 2008 had a factory update reprogramming.


Good suggestion with the re-flash.

Go back to the dealer and check for any re-flashes. If none are available, have them re-set the adaptives for the transmission and drive as you normally would after, so it can re-learn your driving habits.


I've done two battery resets since.. that resets the ECU and the transmission has to relearn shift points automatically as far as I know.
 
Originally Posted By: Pete591
What does it mean on the bottle when it say "not for CVR".?


That should be CVT which wouldn't use the same fluid although they did for a while use the same Z1 fluid but that didn't choice by Honda didn't last long once they realized they are very different transmissions. It is amazing that they ever recommended the same fluid for those.
 
i recalled reading somewhere that DW1 looks more similar to modern universal ATF than Z1, and has less FM compare to Z1. DW1 is full synthetic, and i wonder why your car would shift worse when fully warm up, is it because DW1 is thin or the fluid is still overfill?

i have a 04TSX, and it is using Maxlife now. the AT shift feel very different with the Maxlife. and i expect the DW1 will do the same. i don't think the vibration when idle is ATF related, probably engine mount like you said, you can check out the form on acurazine, 1st gen TSX problem and fix for a quick test/check.... and vibration while accelerating to 100km may be the same issue being report by that forum as well.
if you want to stay with Z1, there are some Z1 floating around kiji around GTA, i brought some coolant, PS fluid, and brake fluid from a guy and he has an amazing price on Z1 (but i did not buy any Z1). some Honda dealer around GTA still has Z1, and may sell you at amazing bulk price.
 
Status
Not open for further replies.
Back
Top