[All Accords] You got Automatic transmission? *you'll WANT to read this*
*UPDATES SEE BELOW*
HONDAMATIC
http://hondanews.com/media_storage/GIF/07CrvLine_14.gif
This is more of an info thread about the H5 series Auto tranny we have in our Euro's (and accords, and CR-V's etc etc). And issues arise from it, figured I'd clear a few things up.
About Honda "Automatic" Transmission (Hondamatic)
Now, Honda auto transmission is unique. Honda auto tranny do not use planetary gears like everyone else. Instead, our trannys are just like a manual with individual gears on parallel axes like a manual transmission operated by stator torque rather than hydraulics. So in essence, it's a hybrid of a automated manual transmission and a normal automatic transmission.
Advantages:
Is that it's more efficient for low torque engines as it sucks less power/torque when used on a 4 cylinder car, and it's physical size is smaller than a traditional automatic.
Disadvantages
... well....Honda auto transmissions are known to operate at a higher temp than other traditional auto's. This is because:
1. It's physical size means less surface/internal area to spread the heat around (think heatsink in your computer), this is not a major factor however...
2. The Main problem is it's design (without plantary gears), clutches cannot be larger in radius than the distance between shafts. As result torque must be handled by a smaller diameter clutch compared to traditional auto transmissions
- IN plain english this means higher operating pressure, greater component stress, as result: more heat, more wear/tear.
So what?
For us 4cyl owners its not THAT bad, the poor buggers are those in V6's (same tranny, HIGHER torque), there were cases of engine overheating from the auto tranny overheating in the Accords in the US. And there had been a class action against Honda about the transmission. In theory, our Euro's should be safe.
- Having said that, the K24 we have in our Euro's are about as torquey as the Honda 4cyl's go. So we'll probably want to be on the careful side.
What do I do?
Frequent ATF change is probably a necessity not a luxury. and in terms of ATF, considering the more stressful and higher temp nature of the honda auto transmission, I'd question the suitability of Honda OEM ATF-Z1, having said that, even Honda had replaced the Z1 with ATF-DW1 earlier this year(2011), DW1 is a new ATF fluid which is said to be more temperature/stress tolerant. DW1 is now the only ATF available from the Honda dealer (2013)
Note: in some countries transmission fluid and filter are replaced much more often than Australia, for example, in China, 4 cylinder accords have a tranny fluid change every 40k km and tranny filter every 80k km.
Alternatives OEM ATF?
There is nothing "special" with OEM Honda ATF, it's not unicorn sperm. Synthetic fluid *should* have a higher flash point (flash point is the temp which the fluid is vaporized)....
ATF-Z1 Alternatives (pre-2010)
ATF DW1 Alternatives (Updated Jan 2016...)
Synthetic ATF-DW1 capable ATF (by the looks of it, DW1 is thinner). Take note: DW-1 seems to be called a different name in Japan - ATF-Z1 *ULTRA*
TTransmission filter? What transmission filter?? (added Sept 2012)
http://hondasto.ru/d/324385/d/image.jpg
The dealership will likely to tell you there is no transmission filter. LIE!
There is a transmission filter. Part number 25430-PLR-003 (SAME FOR CL9 & CU2)
It is serviceable, it sits between the fuse box and the transmission
Pic of the location of the filter (CL9):
http://i203.photobucket.com/albums/a.../Misc/I4AT.jpg
Pic of the location of the filter (CU2 - *ITEM NUMBER 5*):
http://www.oemacuraparts.com/auto-pa...pipe-l4-2-scat
Pic of the filter part:
http://f.rimg.com.tw/s1/f/8b/a5/21112200931237_92_m.jpg
Shift solenoid service!!
Yes there is a way to refresh your transmission by replacing the shift solenoid:
http://www.tsxclub.com/forums/1st-ge.../topics/114698
Further Readings
(Honda auto) Design Limitations Causes Slipping Transmission Clutches
Techanical discussion on Honda Auto tranny
New recall on auto tranny, 1.5 million cars affected (USA)
Honda Transmission problems Seems to Persist (New York Times)
"HotFlashing" ATF change method
An unimpressed Australia Honda customerhttp://www.brisdance.com/Honda/AutoPage.html
Discussing on tranny filter on the Acura RDX http://rdx.acurazine.com/forums/showthread.php?t=803129
Discussion on filters on the Accords (I4 & V6)http://www.driveaccord.net/forums/sh...ad.php?t=14699
transmission codes
RSX, TSX, Accord: (MRMA, MCTA, MCLA, BCLA)
CR-V: (MCVA, MRVA, MZKA, MKYA, GPPA, GPKA)
Update 1 - May 2012
(thank you HONTUNE form hondadynamiks in Adelaide)
ATF-DW1 has now officially entered the country! Honda Australia had advised dealers that all CU2's and Legends must run this fluid.
Update 2 - Sept 2012
added a section re:filter.
Update 3 - May 2013
ATF Filter Alert.
For those who are looking at installing a magnefine filter, please note the patent had lapsed on the filter so there are now Chinese copies around.
I have one such copy on my car now, so far so good but it had been reported that some of those Chinese copies leak.
So if you have a "Raybestos" filter, please check your filter to see if it is leaking and your auto tranny fluid level.
Update 4: June 2013
Updated ATF section, seems the local oil makers (Nulon & Penrite) also make synthetic ATF for Honda Z1, added them for good measure. *support local business*
Update 5: June 2013
Heres a tip on how to drain more than 3 ltr out of your tranny in one go
http://www.ozhonda.com/forum/showthr...=1#post3765617
Update 6: August 2013
DIY guide on how to replace ATF fluid and filter
http://www.ozhonda.com/forum/showthr...77#post3794177
Update 7: Nov 2013
Another good link
http://autorepairservice.wordpress.c...at-low-speeds/
Update 8: Jan 2014
There are now ATF DW1 alternatives on the market, for those CU2/Legend owners... or any honda built post 2011. Seems that Honda dealers have recently jacked up the price of DW1.... it now cost more than the Amsoil equivalent.
Update 9: NOV 2014
Jdm speak: you'll be hard pressed to find atf-dw1 in the Japanese domestic market. It seems that the dw1 is called something else there: atf-z1 Ultra, ultra is just Honda speak for synthetic fluid.
Update 10: Feb 2015, Transmission solenoid. Switch replacement
http://www.tsxclub.com/forums/1st-ge.../topics/114698
Update 11: March 2015, CU2 transmission filter location and part number
CU2 transmission filter sits at a different location than CL9, same part number for filter
Update 12: Jan 2016, New ATF for DW1
Penrite has a new product out, new ATF thats DW1 friendly, it's the ATF LV (low viscosity)
Update 13: June 2017, New ATF for DW1 and Z1 added
this is an interesting development, AISIN, the Japanese transmission manufacturer who makes transmission for Toyota and a large number of European cars, who happens to make automatic transmissions that's a similar design to Honda's have came up with a ATF product. http://aisinaftermarket.jp/en/products/atf/index.html
