2008 Odyssey Transmission "Flush"

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[Linked Image] I have 1 case of Honda DW-1 fluid, which is enough to do 3 drain and fills each drain and fill should remove about 3.5 quarts of the total 8.3 system capacity. The transmission was rebuilt in 2016 and has about 45,000mi on the current fluid, you think I should do 4 drain and fills using 2 quart of Eneos eco ATF that I have lying around and 1.5 quarts of DW-1 for the first drain and fill then dw-1 for the remaining 3 DnFs or just do 3 with only the Honda fluid, assuming the fluids all perfectly mix each time, however if I did 3 DnF with only Honda fluid I'd leave about 1.6 quarts of the old Fluid in the transmission. If I do the 4 I'd leave around 9/10 of a quart of the old in there and there would be about 2/3 of a quart of the first fill left in there and about 43% of that would be Honda and 57% would be the enos so that only leaves about 4/10 of a quart of the non-Honda fluid in there which shouldn't dilute the Honda additive too much. Is it worth the extra DnF with the non-Honda fluid to get and extra 2/3 of a quart of the old fluid out.
 
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I think you're way over analyzing this. If this was my car, I would drain and fill with a Honda or compatible fluid every 2nd or 3rd oil change and call it good.
 

blufeb95

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Originally Posted by ripcord
I think you're way over analyzing this. If this was my car, I would drain and fill with a Honda or compatible fluid every 2nd or 3rd oil change and call it good.
That's a great for regular maintenance,but these trannies on the 05-10 Odysseys are known to be made of glass, I'm pretty sure you're supposed to change the fluid out at 30,000mi and it's now at 45,000mi. This is actually my mother's vehicle, if I'd have thought about it when she had the transmission replaced in 2016, I'd have drained the fluid once a year to make sure that the fluid stayed fresh.
 

CT8

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What was the cause of the failure? Was the failure oil caused? I prefer cleaner oil but oil won't help poor design or low quality of parts.
 
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Stick with the dw1 and don't mix. While mixing won't cause any harm, the transmission will operate best with the specified dw1 fluid. In my 2002 Honda Accord I tried all different types of transmission fluid. When I finally tried the dw1 I couldn't believe how much better it shifted. So now I bite the bullet and that's all I use.
 
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Going to guess clutches fried due to factory shift calibration for silky smooth and early engagement for comfort and mileage (reason for 30k service interval specification to keep pump pressure at optimum).
 
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Originally Posted by ripcord
I think you're way over analyzing this. If this was my car, I would drain and fill with a Honda or compatible fluid every 2nd or 3rd oil change and call it good.
^this Eneos Eco is Honda compatible and the Honda will be fine whether you use DW1 or Eneos Eco for full or partial fill.
 

JC1

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Originally Posted by ripcord
I think you're way over analyzing this.
+1. Change the fluid now (drain and refill) and then change the fluid once a year going forward unless you drive a ton of miles in a year (then change it around 25-30K miles max). Are you towing with the Odyssey?
 
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No rational reason to fear a "flush". I have yet to see any shop with any type of forced flushing. All use a completely passive unit which is nothing but two reservoirs. Your trans does the work and nothing is flushed or forced in any way, fluids only flow in the same pattern as normal operation. I have had amazing results with this procedure. BTW, my expert trans rebuilder says he does a lot of those Hondas...
 
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I'd do 3 drain and fills with the DW-1. If I were really OCD, which my wife and kids say I am, I might consider 4 DnF. But, after doing 3 I would probably quit. Then do it every 25k after this time. Only use Honda Fluid that was specifically designed for your AT. I respectfully disagree with doing any AT flushes. It may work out fine 90% of the time but I don't want to be in the 10% mess up category. After 1st DnF = 42% new fluid After 2nd DnF = 67% new fluid After 3rd DnF = 81% new fluid After 4th DnF = 89% new fluid After 5th DnF = 94% new fluid After 6th DnF = 96% new fluid After 7th DnF = 98% new fluid
 
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I have an 05, A couple years ago I did 3 drain and fills with Valvoline Maxlife (red jug) because I wasn't sure of the transmission maintenance history. And now I do one every 2 years or 20-30K. Also, never do a true "flush". Just drain and fills.
 
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It's actually funny the OP put the word flush in quotes. Do a pan drop and a filter change, refill and call it.......................................................a flush. Do a drain & fill using a drain plug equipped pan and call it.........................................a flush. Disconnect a cooling line and do a pump-out and call it...............................................a flush. Attach a forceful machine to your rig and powerfully hose it internally and call it.........a flush. Use the passive machine SteveSRT8 mentioned and call it.........................................a flush. Throw chemicals into a neglected transmission, clog it up and call it...........................a flush. And this doesn't touch the questions regarding: 1) Transmissions which are already damaged or dead not responding to...............................................................a flush 2) Dishonest jackals who knowingly use the incorrect fluid (aka the cheapest stuff they can buy) during...............a flush That's why I say, "Keep it clean in the first place".
 
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I did similar to jay, using MaxLife ATF when I got my 06 Ody at 134k. Fluid looked like it had never been changed prior, and shifting was terrible. I did 4 1-gal D&Fs with ML, and shifting improved tremendously. After that, I performed a single 1-gal D&F every other OCI, which worked out to around 15k miles. Now, 75k miles after my initial ML introduction, the trans shifts just as good as the 4 D&F episode, and has never been out of the vehicle. I'm not a fan of mixing ATFs, so I would just use your DW-1 and buy more if you want to complete more flushes. FWIW, Honda manual calls for 4 total D&Fs with a short break in between to run the trans thru the gears and circulate all the fluid to consider the transmission fluid "changed".
 
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Originally Posted by SubieRubyRoo
I did similar to jay, using MaxLife ATF when I got my 06 Ody at 134k. Fluid looked like it had never been changed prior, and shifting was terrible. I did 4 1-gal D&Fs with ML, and shifting improved tremendously. After that, I performed a single 1-gal D&F every other OCI, which worked out to around 15k miles. Now, 75k miles after my initial ML introduction, the trans shifts just as good as the 4 D&F episode, and has never been out of the vehicle. I'm not a fan of mixing ATFs, so I would just use your DW-1 and buy more if you want to complete more flushes. FWIW, Honda manual calls for 4 total D&Fs with a short break in between to run the trans thru the gears and circulate all the fluid to consider the transmission fluid "changed".
Interesting info. Thanks!
 
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Originally Posted by Kira
It's actually funny the OP put the word flush in quotes.
Honda calls multiple drain and fills a "flush". Yes, it's contrary to the old-fashioned method of what a "flush" is but in Honda's case, they want their own definition.
 
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Originally Posted by blufeb95
I have 1 case of Honda DW-1 fluid, which is enough to do 3 drain and fills each drain and fill...
Use the Honda fluid. Nothing else.
Quote
...assuming the fluids all perfectly mix each time, however if I did 3 DnF with only Honda fluid I'd leave about 1.6 quarts of the old Fluid in the transmission. If I do the 4 I'd leave around 9/10 of a quart of the old in there....
On paper or mathematically, this is the case. In reality, it's not. As others have said, you're overthinking this. Keep it simple. Do a single drain and fill every "x" miles (I'm not aware of Honda saying every 30k miles, although many dealers do and that's not the same thing), using DW-1, and it will be fine. If it does fail, it won't matter if you had changed the fluid weekly.
 
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