Chas2

I came across this in the TQI for the 2011 RDX. The 2011 RL is not out yet, so I don't know if it uses these new fluids, but my question is more to the point, are these new fluids backward compatible for ATF-Z1 uses, namely the RL rear diff and transmission??

I would give the link, but Honda has recently closed all the links that I used to have that would give you Owners Manuals, Service News and TSBs. I just happened to have downloaded a copy of the TQI a few weeks ago, so here is an excerpt from the pdf of B10-020

New Automatic Transmission Fluid

A new automatic transmission fluid is used starting in
2011 models. ATF DW-1 is the new automatic
transmission fluid that helps improve low temperature
performance. Do not use any other transmission fluid
n 2011 models.

New AWD Differential Fluid

A new differential fluid is used in all 2011 SH-AWD
models. Acura All-Wheel Drive Fluid (DPSF)
replaces ATF-Z1 as the recommended rear differential
fluid. Acura All-Wheel Drive Fluid is designed
specifically for the tough conditions in the AWD
assembly.

Acura All-Wheel Drive Fluid (DPSF) is a caramel color,
not pink like the previously used A/T fluid. The rear
differential case is also stamped with the letters DPSF,
not ATF.

LeftCorner

iTrader: (1)

Yes, it is. Our dealership no longer uses ATF in any of the SH-AWD equipped vehicles. The bottles of AWD fluid also state that it is now to be used in place of ATF.

2007-RL-Tech

I have noticed on my 07 RL that when I reach the 14k mile mark (it has now happened twice) I get a slight shudder from the rear. Both times it came back that the diff fluid needed to be changed a bit early. My service tech said that other folks don't notice it but it happens in all SHAWD vehicles.

The moral of the story is that Acura should bump up the service interval for the diff fluids because any shudder is likely to be bad for the longevity of the transmission and differential.

LeftCorner

iTrader: (1)

Anh85

Thanks for the info, I guess I need to get that fluid the next time i do a tranny flush.

TonyCD

...because I just read up on a bunch of the old threads and at BobIsTheOilGuy, which is usually another great resource on this stuff.

Since it took a bit of effort to piece together a consensus from all this information, I thought it might be helpful to others if I summarized it here:

•Honda's new tranny fluid is suspect to me. It sounds like the change was made because of production constraints and environmental considerations, not for the well-being of our transmissions. I base this conclusion on several bits of evidence, including:

1) The old Z1 fluid was considered suitable for both our transmission and our rear diff; the new DW1 is approved only for the tranny.

2) Honda is telling people that if their transmission is shifting roughly with DW1, the remedy is to drain out a quart of the DW1 and replace it with a quart of the old Z1 (!).

•Honda is now recommending that our rear diffs use a new fluid called Acura DPSF. It sounds like this is identical to the existing and less expensive Honda DP2 fluid that's used in lower-tech Honda AWD vehicles like the CR-V. So, when your Acura isn't under warranty anymore, you can save accordingly.

•For the transmission, the new DW1 is a semi-synthetic blend -- basically a Dexron 3 ATF with the addition of a "friction modifier" that smooths out the shifts (without improving transmission durability). Most Dexron 3 fluids don't have the friction modifier, but there's one that does: Valvoline MaxLife Dexron/Mercon ATF, which offers the added advantage of being a full synthetic and therefore probably more robust than the Honda fluid. (Note that Valvoline markets more than one ATF under the MaxLife name; you need the Dex/Merc one specifically). Valvoline's website specifically says it's approved for Hondas and won't void warranties. Mobil 1, on the other hand, specifically now says its ATF is NOT certified for Hondas. Amsoil universal full-synthetic ATF also is well recommended, but less widely available.

What I did: 3 gallons of Valvoline, to accommodate three successive drain-and-fills at an independent shop. This approach cost me over $150 between the labor and the fluid, but it's the best combination of safe no-flush practices and best-quality fluid that I can think of except maybe for the Amsoil. For the rear diff, I used Acura's fluid because the car is still under its CPO warranty, but I expect I'll go to the Honda fluid afterward.

As an aside, a lot of people smarter than me seem to think that both the transmission and the rear diff would benefit from more frequent fluid changes than I realized. Although it may be an overreaction to the earlier failures of Hondas and Acuras that had a different, smaller transmission than our RL's, some suggest that the transmission fluid be changed as often as every other oil change.

oo7spy

I could see justifying a tranny change that often if you were not doing 3x3 flushes. The manual states 30k for a very worst case scenario, so a single drain and fill every 10k should be acceptable.

TonyCD

Good point, 007. Of course, either way gives you three partial drains every 30,000 miles, so the single-drain at every 10k is really just doing the same thing on the installment plan.

TonyCD

Agree, this is BS. It's never happened to me in over 100,000 miles, Consumer Reports reliability surveys have not singled out SH-AWD as a trouble spot, and I talked to an Acura lifer mechanic who told me personally these components very rarely give trouble.