ATF+4 substitute...syn Dex3/Merc

[ac_tc]

Ok, i know im opening a can of worms here but...
A quart of +4 is 13$ and i can get syn Dex/merc for 3$/quart.
So:
-Has anyone used syn Dex/merc in a 46re transmission?
(The 46re is an sibling of the 727/ 518 and 46rh, basically
an electronically shiftpoint controlled overdrive 727.
Used behind the magnum and cummins engines.)
Since the elctronics doesent control shift quality it should be ok to use dex unlike the "more modern" mopar transmissions.
-Any thoughts?

 

[Astro14]

There are a lot of factors in fluid specs besides the control systems (electronic, etc...) of that trans application.

If the fluid doesn't meet the spec that the trans calls for - don't use it! I've seen several examples of trans failures in Aisin-Warner transmissions when the wrong spec fluid was used. Sure Dex/Merc and universal are close to the T-IV/JWS-3309 that was called for in the those applications, but they caused the trans to operate poorly and then fail...

Bottom line: what fluid does your trans call for?

 

[meep]

Originally Posted By: ac_tc
Ok, i know im opening a can of worms here but...
A quart of +4 is 13$ and i can get syn Dex/merc for 3$/quart.
So:
-Has anyone used syn Dex/merc in a 46re transmission?
(The 46re is an sibling of the 727/ 518 and 46rh, basically
an electronically shiftpoint controlled overdrive 727.
Used behind the magnum and cummins engines.)
Since the elctronics doesent control shift quality it should be ok to use dex unlike the "more modern" mopar transmissions.
-Any thoughts?


USE ATF+4.

This IS an electronically controlled AT. That is where the exact cause for early failure ties to. ATF+4 is "more slippery." the dex/merc will grab too soon, the computer will sense it and start pulsing the clutches in and out to maintain control of shift quality. = premature wear.

this is the #1 reason for shortened life in so many caravans... engineers designed it for a struct fluid type, but the AT filler cap and dipstick even said DexIII was an acceptable substitute.

Don't go cheap. even supertech atf+4 is very reasonable and FAR FAR better in this app than the wrong fluid.

 

[caravanmike]

13$ for atf+4? you are looking in the wrong place. my local walmart has it for 3.77$

 

[demarpaint]

Originally Posted By: caravanmike
13$ for atf+4? you are looking in the wrong place. my local walmart has it for 3.77$


The OP is from Sweden, that could have a lot to do with it.

OP use ATF+4

 

[rslifkin]

In the 46RE in your Durango, ATF+4 is definitely the best choice. However, those transmissions won't die if you feed it a good quality Dex. While they're electronically controlled, they don't do anything fancy as far as shifting, and most of the shifting is electronically controlled hydraulics anyway. Plenty of them live just fine on other fluids, although I'd be wary of mixing (changing to something different with just a pan drop). The biggest thing is to keep the fluid clean and cool.

The Caravan transmission was a different case, as it uses full electronic control, partial TC lockup, and can vary shift firmness electronically. However, the 46RE can't electronically adjust shift firmness, so if you feed it grippier fluid, it'll just shift a bit harder.

 

[unDummy]

https://bobistheoilguy.com/forums/posts/1586772/

 

[ac_tc]

Well, the question is still if anyone has used or
uses dex3/merc in one of these transmissions and how it behaves.

 

[rslifkin]

I haven't personally, but I have seen it mentioned elsewhere on the internet. IIRC, people said it shifted a hair firmer. I'd google it (don't remember what forum I saw it on) and see what comes up.

 

[Audi Junkie]

ATFs are a LOT more interchangable than people think.