Tranny fluid

[37 guy]

Have a fresh rebuild on my 727 automatic tranny. What fluid would u recommend?

 

[tedsweet]

atf 4

 

[slacktide_bitog]

Welcome to BITOG

If it calls for ATF+4, the best thing to use is Redline C+

 

[Chris142]

It calls for dexron 3

 

[blufeb95]

Some folks like to use Type F for firmer shifts, Dex/Merc is closer to what was originally called for, ATF+4 is acceptable because Chrysler dealers don't carry Dex/Merc anymore and Chrysler tested ATF+4 and said it works well enough. I'd be inclined to use cheap DEX/MERC or Aliison TES-295 approved fluid if you want a higher quality synthetic.

 

[joegreen]

The good news is you can use virtually anything and be fine. I would probably use whatever the cheapest general atf you can get. Maybe supertech dex or something similar.

 

[GMBoy]

In addition to all the suggestions above - what did the trans rebuilder put it in an recommend?

 

[Lubener]

Chrysler veered to ATF+4 and GM veered to Dex 6, so I would go with ATF+4. You likely won't be able to find earlier fluids. DEX/MERC is probably the only other acceptable fluid you might still find. Don't use a low viscosity fluid like DEX 6.

 

[Donald]

ask what is required to maintain the warranty I hope you got.

 

[Donald]

I use only Amsoil ATF and gear oil. For motor oil I buy that at Walmart.

 

[hrv]

Have a fresh rebuild on my 727 automatic tranny. What fluid would u recommend?

the best tranny Chrysler ever built....Great for drag racing..

 

[zrxkawboy]

I would use your fav name brand Dex/Merc.

 

[kschachn]

Chrysler veered to ATF+4 and GM veered to Dex 6, so I would go with ATF+4. You likely won't be able to find earlier fluids. DEX/MERC is probably the only other acceptable fluid you might still find. Don't use a low viscosity fluid like DEX 6.

But on the other hand part of the DEXRON-VI licensing requirement is improved shear stability over what was required for DEXRON-III. So even though the -VI fluid starts off slightly thinner, it retains viscosity better than -III and will end up more stable than a -III fluid. DEXRON-VI fluids are superior to the old (and no longer licensable DEXRON-III) in every aspect, not just viscosity retention. DEXRON-VI is not a "low viscosity" ATF.

 

[zrxkawboy]

DEXRON-VI is not a "low viscosity" ATF.

I agree with everything you said, except for this. Starting viscosity determines whether an ATF is low viscosity, in my opinion . For example, Dex VI is essentially the same as Mercon LV, and we know what the LV stands for.

 

[Lubener]

But on the other hand part of the DEXRON-VI licensing requirement is improved shear stability over what was required for DEXRON-III. So even though the -VI fluid starts off slightly thinner, it retains viscosity better than -III and will end up more stable than a -III fluid. DEXRON-VI fluids are superior to the old (and no longer licensable DEXRON-III) in every aspect, not just viscosity retention. DEXRON-VI is not a "low viscosity" ATF.

ATF+4 is pretty stout too and is a closer match. If he plans on regular transmission maintenance, shearing won't be much of a factor since even old DEX 2 would have no problem making it to 30k miles.

To the OP, I would ask your question on ALLPAR's forum. There is the greatest collection of Mopar know how there and you will get your best answer there.

Allpar Forums

A forum community dedicated to Dodge, Jeep, Ram, Chrysler, AMC owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more!

www.allpar.com

 

[zrxkawboy]

^^^I agree that ATF+4 is a stout fluid, and close to Dex3 in viscosity. I’ve never tried it in an old Torqueflite though…not sure how those units would work with a HFM ATF.