Discussion in 'A Body: Duster, Valiant, Dart, etc' started by voiceofstl, Feb 9, 2016.
What kind of fluid should be used now for 727 and 904 from the 60's and 70's?
ATF+4 is the recommended replacement for ALL Torqueflite transmissions, per Chrysler.
If i remember correctly dex3 was recommended along time before mother started inventing her own.
I would be cautious to use the modern lo-viscosity fluids like dex6.
Anyway, they run fine on dex, type f or almost whatever.
While the synthetic oil and additives content of modern ATFs may have advantages and beneficial characteristics for any automatic transmission, it was not what they originally came with. The MS-7176 fluid is considered obsolete.
Any transmission from the 60s-70s has probably been through a rebuild or 2 since new. The clutch lining material may be factory or aftermarket. Different lining materials may prefer different fluids.
My neighbor had his 41TE rebuilt by an independent shop that used Royal Purple. They told him that adding any other fluid than the Royal Purple would void his warranty with them. It made it difficult for me to suggest to him that ATF+4 (MS-9602) is the preferred fluid.
I don't think that any particular ATF would actually harm the transmission life and ATF+4 would be a good choice.
ATF+2 and ATF+3 has superseded to ATF+4. More info here:
Chrysler transmission fluids: 7176, ATF+3, ATF+4
ATF+3 or ATF+4 both work fine.
You can still get universal fluids that claim to be Torqueflite compatible.
I only use Type F on all my non electronic automatics as it firms up the shift.
I don't think you intended to say this IC, but that statement could be read as you can use any transmission fluid you choose and it won't actually harm the transmission life.
Using the recommended ATF or an equivalent of equal or better quality and the right properties, won't harm the transmission life.
From best I can tell, the only ATF's more durable and higher quality than ATF+4 are the exotics, like Royal Purple, Redline, AMSOIL and maybe Mobil1 Synthetic ATF.
So, if you have a late model transmission that specifically states to use only ATF+4, we all know what happens when you use DexronII, Mercon or TypeF. But anecdotally, I've read accounts of folks using Royal Purple, Redline, AMSOIL and Mobil1 Synthetic ATF and reporting the trans worked fine and did NOT shorten the trans life.
In this case a TorquFlight 727 and 904, that DexronII was originally recommended for and Chrysler/FCA now recommends to retrofit to ATF+4 if changing the fluid, you're going to a more durable, higher quality fluid, the only argument is if you're wasting money with overkill on better than needed ATF. Or you can use the even better exotics I spoke about.
I'm guessing you agree.
There was an article about using Dexron6 in the 727/904's that originally recommended DexronII. It was discussed on the forum. I think most agreed with the article, that a 727/904 that originally DexronII was recommended, you could switch to ATF+4 or Dexron6, both would be a better fluid. A few disagreed and worried the Dex6 has some different properties and lower viscosity than the orginal recommended fluid and suspect it might NOT protect as well. But then again, ATF+4 has many different properties than the original DexronII.
Great info, Rick. 'Over-kill' or not, it is always wiser to use newer spec. fluids in older vehicles than the other way around. Same thing with engine oil. Look how the grades have changed since the sixties and those ancient (ML - MM - MS - SC - SD- SE- etc.) grades are no longer available for those of us with vehicles of that era. Today it's as simple as using the best available 'fossil-oils' and sometime, in right situation, synthetics. Any oils that state "Diesel" can obviously be used in gas or propane engines - for better protection and longer life. Your engine will love you for it - - - tranny, too.
Actually that is NOT always true. The latest engine oil spec SM? Reduced the amount of zinc oxide in the oil, to increase the life of O2 sensors and Catalytic Converters in modern vehicles. The zinc oxide is a high pressure/impact additive to protect during metal to metal contact, it is needed for the interface between Cam and flat faced lifters. Since all modern cars have roller cams/lifters for the last 15 years, SAE decided the Zinc in the oil was no longer needed, and only hurt the O2 sensors and Catalytic Converters and thus removed it from the spec for the latest oil.
And to be honest, many have said that if the cam/tappets are well broken in, the zinc oxide is NOT necessary, few have had problems using the newer oil spec. BUT, if you've rebuilt a classic motor, and need to break in a new flat tappet cam, people have found the new cams whiping out using the new oil spec.
I had a '95 Jeep Cherokee with the flat tappet cam, I always got the Mobil1 Oil for "Older Vehicles" cause when I checked the SAE certification, it listed spec SL (probably because of the flat tappet cam thing) and I used that in my flat tappet cam engine.
The older torqueflites used dexron ATF, and they lasted a long time even when people rarely changed the fluid. Because ATF+4 uses different chemicals, I would shy away from using the +4 type in an older tranny. Unless it has been rebuilt with a fresh kit, recently. My concern is that the new chemicals might affect the bonding agents on the bands and clutch plates of a 40 year old tranny.
Different oils have different purposes. One size does not fit all. I use Mobile1 20w50 V-Twin motorcycle in my old flathead Briggs lawn mower engine because it is rated SH. [better for sliding friction and better for high heat]. The older 340 engines had some pretty high valve spring pressures, and an oil with better sliding properties is necessary.
Dexron 2 was the original recommended oil.
Most guys with modified TFlite cars use Type "F". or very expense Racer brands.
Type F firms up the shifts, like the race fluids.
That is because type F has no friction modifiers. Dextron has some friction modifiers, and ATF+4 has highly concentrated amounts of friction modifiers.
If the olderbspec ATF is unavailable (and it isnt) use the latest spec, +4.
Stipdick on the Dakota says use +3. It's no longer made.
When I first bought my Dakota a few years back I took it on a trip. Kept smelling ATF. Got to Nashville and the check engine light lit and it ran like crap. Checked th3 ATF and it was foaming, so I went to Ma MoPar. They changed the O2 sensor and I had them change the ATF and filter. They used +4.
And NEVER use the universal fluids or off brands.
The "exotics" are fine as long as they meet +4 specs.
My m/c has flat lifters and it's fine as long as I use the proper viscosity (20-50) all is well. Newer bikes ate being spec'd 10-60 due to running them epa lean (read hot).