AW4 fluid

cjsxj87

NAXJA Forum User
Location
Connecticut
Yes a beat subject but....
I would like to change my tranny fluid(aw4) and was wondering Ive read ONLY DExron III, but my buddy who works for Jeep swears that ATF+4 is what they use and good for the tranny. So What should I use? DexronIII or ATF+4
 
crap...I was just at autozone and asked the guys and was told by them "dex/merc" 4 quarts. they looked in computer. Hope thats correct.

FWIW haynes list it as Mercon, would dex/merc work as well?
 
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the AW4 was designed to use Dex II. But this is no longer manufactured, has been replaced by Dex III and IV. Auto zone Dex/Merc is Dex III. Chrysler ATF +4 is rated to cover Dex III and lower grades. I don't BUY ATF anything for my XJ because grades lower than +4 are bad for it. Use only Dextron II , III or IV or Dex/Merc in a AW4. Also if vehicle make is listed, use those rated for Toyota before using those for Chrysler, the AW$ is a Toyota Tranny not a Chryco.
 
Its funny, I was at auto zone the other day and I asked them what I needed ( I read Dexlll online, but wanted to see what there computer said) They told me ATF+4.

Went with the Royal Purple........
 
Dex II is what the manual call for. So anything Dex II, III, or IV is OK.

FWI, I read somewhere, might have been a bottle of fluid, that Dex V is not compatable, with Dex II or Dex III.
 
Amsoil Universal ATF
 
The correct fluid is Dex VI (6). The manual calls for Dex III but that is no longer licensed for production so the only "Dex III" you find anymore is the manufacturers idea of a "compatible" fluid. Dex VI is the current licensed version of Dexron (it must conform to the specifications to carry the label). Dex VI is backwards compatible with previous versions and can be used in anything that calls for Dexron II or III.

Mercon was almost the same as Dexron back in the II (2) days but has become increasingly different and is significantly different now. Even Mercon IV is incompatible with Mercon II.

There was no Dex IV (4) or V (5), it went from III (3) to VI (6)
 
Yep, transmission fluids are developed by the auto manufacturers and then licensed for production by the oil companies.

ATF+4 was specifically PROHIBITED by Chrysler for use in the AW4 transmission until a TSB released in June 2007. At that point Chrysler waved their magic wand and ATF+4 was approved for use in the AW4, a transmission designed by Aisin Warner to use Dex--don't you just love magic? This magical event just happened to coincide with the fact that Chrysler is no longer using the AW4, and all extant AW4s were out of warranty by that time--magic, right?
 
Beating a dead horse some more, but...
Reading on Alldatapro.com (shop info service) I've found the TSB for CHrysler saying to use ATF+4. Ok, cool - but what does Toyota say for the A340 (almost identical trans) ?
ATF Type T-II or T-IV. Toyota-specific fluid.

As I see it, there are a few ways to look at this:
1. Both Toyota T-IV and Mopar ATF+4 meet or supersede all important specs of DexIII.
2. Both companies want you to destroy your AW4 / A340 with the wrong fluid, prompting you to buy another (newer) Mopar or Toyota product
3. Mopar wants to kill your AW4, while Toyota is recommending the correct fluid
...etc
Here is the bottom line: It was designed for DII, which DIII superceded. If you can find a quality DIII and keep the transmission full & filtered... you *know* that it is what Aisin intended for the slushbox. Anything else is suspect.
 
Yep, transmission fluids are developed by the auto manufacturers and then licensed for production by the oil companies.

ATF+4 was specifically PROHIBITED by Chrysler for use in the AW4 transmission until a TSB released in June 2007. At that point Chrysler waved their magic wand and ATF+4 was approved for use in the AW4, a transmission designed by Aisin Warner to use Dex--don't you just love magic? This magical event just happened to coincide with the fact that Chrysler is no longer using the AW4, and all extant AW4s were out of warranty by that time--magic, right?

I agree. In 2007, CHRYSLER decided to change their recommendation to ATF+4. Not Asin Warner (the AW4 mfg), but CHRYSLER.

So from the first AW4 off the line until 2007, the recommendation was Dex/Merc.

The AW4 transmission didn't change, and there has been some discussion by insiders about the 2007 Chrysler TSB calling for ATF+4 to have more to do with "logistics" in the parts department and "profit" for Chrysler than anything else.

As there have been more than a few on this and other XJ forums that have experienced excessive slippage with ATF+4, (not all to be fair) which then goes away when the owner switches back to Dex/Merc, that strengthens the case for staying with Dex/Merc.

My vote is to stick with Dex/Merc III compatible. Yes, true licensed Dex/Merc III isn't available but you can find the Dex/Merc III compatible fluid anywhere.

But this saga will continue.................
 
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hi man, after rebuild my trany, mecanics filled with dextron, it was the right one for AW4, but when started the engine, I mean "cold" the trany "kicked" (terrible movement) until the engine reach its normal temperature.

After this experience I read an article that ATF+4 work out with AW4, taking care about this, I changed the fluid and WOW this change yield soft shifting even when the engine is cold.


after 5 months is OK. Remember my trany was rebuild, almost new if you can take it like that, so take your precautions, because I heard about someone who broke down his trany, mine WAS REBUILD I thought that's why it succeded !!!
 
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Amsoil Universal ATF here. Shifts better than it did before.
 
ATF+4 can hold up to higher temps than Dex III. Since heat is the main killer of autos this is a good thing. I think you have a much better chance of ruining your tranny by power flushing it than you do using ATF+4.
 
Ok, cool - but what does Toyota say for the A340 (almost identical trans) ?
.

My 07 Tacoma with the A340 calls for Toyota TYPE T-IV fluid. I think I remember being around 5 or 6 bucks per qt at the dealer. Someone willing to experiment?
 
Hmm, I didn't realize the A340 was still in use. It makes some amount of sense for a manufacturer to kill off its out of warranty transmissions - but not an 07.

I think T-IV would work well in the AW4. In fact, I'm about sure of it.
 
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