transmission oil, part deux -- automatiques

[andrethx]

rather than threadjack dave's thread on oil for (manual) transmissions, i decided to start a new thread to discuss automatic transmission fluid. rabin and i have been discussing this off-forum, and i decided to open the discussion up so that we could all benefit.

back when our cars were new, GM's dexron ii spec was current, and that's what peugeot and ZF (the OEM for the automatic transmissions in the 505s) specified for the 4hp22 transmission. time has moved on, and dexron ii is no longer available in the US, as far as i can tell. GM's dexron spec has been revised multiple times since then, and since the newer dexron specs are (by and large) backwards compatible, generally the advice one gets here is to simply run high-quality dexron iii or dexron iv atf.

however, i have read in a number of places that the issue is not quite so simple, that our transmissions actually work better when running true dexron ii (which is available outside of north america):

http://www.505turbo....t__20#entry5655

http://www.aussiefro...ead.php?t=32005

http://www.aussiefro...ead.php?t=93470

http://www.aussiefro...ead.php?t=25121

plus numerous threads on peugeot-l, those of you who are members can search for "dexron ii"

the first AF link contains a link to zf's official list of approved atf formulations for its various transmissions. it should be noted, however, that this list is not continually updated -- that is, ZF has not updated its recommendations for the 4hp22 for many years.

in light of all of this, i ordered dex ii fluid from the UK:





after i run this for a couple of months or so, i plan to change the atf again (using the same stuff). of course, i'll report back on how it goes. but those of you with automatic transmissions -- what are you running? how do you like it?

andré

[Bean]

My plan for the TD wagon is to run a synthetic ATF that specifies that it meets Dexron II specs. AMSOIL universal ATF and Redline ATF both specify Dex II so I'm hoping it should be OK. My V70R has a very delicate transmission and the ATF is quite special and it needs to meet 3309 specs which hardly any do. Mobil has a specific 3309 ATF - so I used that oil to help flush the ATF out, but I used AMSOIL universal ATF in it as well as it specifies that it meets 3309 specs as well. 80K kms so far and the transmission shifts awesome still. (Knocks on wood!)

I've also got two spare unknown 4HP22's and 1 known good 4HP22 in the garage so I'm well prepared should anything happen. I really would like to eventually try my hand at rebuilding one of the spares of unknown condition, but it's way down the list. All three are out of Turbo gas cars though - so I'll have to swap some parts over regardless should the TD tranny fail.

Rabin

[Bean]

From Facebook - Alan Hood

So this has been fantastically debated in the Citroen forum on AussieFrogs. The key arguments centered around the words and phrases "compatible, meets requirements, recommended, etc". There are definite differences between Dexron II and III. The ZF 3HP and 4HP were designed for II and many Citroen CX owners reported issues when switching to III. Both ZF and Citroen said Dexron III was compatible, which is pretty much all they could say because GM owns the Dexron brand and had already transitioned to III. Advocating that owners hoard the older formulations of Dexron was not really an option at that time. Compatibility does not equal ideal, or designed for, it just means that bare minimums can be met or that specifications have been exceeded. But is that a good thing? Modern ZF transmissions (and others) have evolved in technology, materials, operational conditions, etc. The Dexron fluid today is geared towards modern transmissions. I'd bet that today not an hour of testing was done on transmissions that were designed and created in the late 70's & 80's. All they are doing is insuring that the API specs back then are met or exceeded. That's all you can do if you wish to stamp Dexron in big fonts on your product. However there are other options. I'm not sure how they are even able to use the Dexron II name when referring to compatibility, but Morris Lubricants offers a product called IID that is the fluid you should be using. It is sold here and I have found it at specialists that cater to Jaguars. (Morris also makes LHM) 

http://www.morrislubricantsonline.co.uk/liquimatic-dii-atf-transmission-fluid.html

[andrethx]

it looks like the morris lubricants web store is down at the moment. i got my castrol dex ii from amazon UK, they still have it but with shipping it isn't cheap. unfortunately amazon UK doesn't sell the morris lubricants product (though they sell other ML stuff).

[Rob57]

The original fill for Dextron II was Mobil ATF 220. The cars were shipped over dry and OEM TOTAL Lubricants weren't available here.  Dextron III-H is listed as an acceptable replacement, but ABSOLUTELY nothing higher in terms of specifications or serious damage will result!  ELF Petrofina/TOTAL (a single merged corp now) calls Dextron II, D2 on their product labels and they still offer it around the world.