Honda DW-1 fluid

I have a 99 Accord that I need to change the transmission fluid on, and the owner’s manual specifies Z-1 which wasn’t available at the dealer. I was given DW-1 which is the “new formula” and I just wanted to make absolutely sure that it meets the specifications of the Z-1 and is backwards compatible with? i.e. since all the fluid won’t be drained, the two will be mixed together. I don’t want to do more harm than good by doing this maintenance. Thanks,

They MAY or may NOT be.

Check with the Honda Dealer.

Example of what I mean…Nissan required gear oil SL-4 for their transfer cases. GL-5 came out and said it was backward compatible. It ISN’T. GL-5 contains sulfur …and some components in the Transfercase contain brass…which sulfur will eat. So even though GL-5 is suppose to be backward compatible…it ISN’T.

The information superhighway lets us down again, no official word from Honda. But at several Honda forums, they are saying that it is backwards compatible and will mix well with Z-1. They also say it greatly improves low temperature shift performance which has been a chronic problem for Honda ATs.

One more thing to note, by law, an auto manufacturer has to provide all parts for their cars for at least 10 years after the date of sale, so if this fluid was not backwards compatible, they would have to carry the Z-1 for at least ten years after the last Honda to use it was sold.

I see you do not intend to do a flush, that is good, Most flush machines are not good for this transmission and Honda recommends against any type of flush except for flushing out the cooling lines and cooling coil to/in the radiator.

It appears that you bought the fluid at your Honda dealer. They are the experts and will have to stand up for their recommendation if anything goes wrong. Just keep your receipts. And you might want to send them an email or letter to document the issue in case there is ever a problem. I doubt that there will be any problems, but if you need a little CYA, that will do it.

Hi Accordion: I have a 06 Honda CRV which calls for Z1 . I did a drain & fill about 6 months ago , about 3 litres came out ,I put in 3 litres of the new DW-1 no problems at all ,works fine. This new DW-1 is synthetic .
Signed Honda Bill

I think I will be okay based on a quick peak at some Honda boards, and today my dealer confirmed that the DW-1 will mix with Z-1. Thanks all.

Official info here>>>

A place I do mail order from sent me that link when I asked same q for my 07 MDX.