Thoughts on ATF+4 in GM 4T60-E

[Wampahoofus]

Before the raging firestorm ensues, I know +4 is not the spec fluid for this trans and won't yield any major benefits besides enhanced longevity and more consistent performance. Now, carrying on:

Does anyone have prior experience using Mopar ATF+4 in a GM trans that originally spec'd Dex-III? I have a bunch of it on hand and would like to take advantage of its more-consistent performance and longer service life compared to Dex-III. I would be using it in a 2000 model 4T60-E with 180k miles on it. It has had the fluid and filter changed at least once around 100k, so it shouldn't be on the verge of complete death. I'm unsure if it's been done more than that.

After studying Chrysler's SAE paper 982674 my gut reaction is that it would be fine. Both fluids are nearly identical in terms of cold and hot viscosity, and perform very similarly in service (until the Dex begins to degrade). Backing that feeling up, Chrysler superseded many of their Dexron-II factory-filled units' fluid with the ATF+ series. In the early days of the A-604 they also claimed ATF+ and Dex-III were interchangable (though we all know how that turned out in the Chrysler transmissions).

"If you want a good synthetic fluid, why not use Dex-VI? GM said it's ok for your application." - I would, but I have a ton of +4 lying around.

Thoughts? Feelings? Objections? All much appreciated

 

[FL_Rob]

It's about the friction modifiers .The ATF+4 has less than DEX 3 and way less than dex 6.will it work ?,yes all the way until the the PWM programming tries to slip the the clutch packs more and more until they're gone ..maybe a mix of DEX 3 or 6 and ATF+4 will work but real expensive if it won't.
I would be a little concerned about changing fluid composition on a trans that only had one change at 100k and now is on 180k also this could "make it or break it" as they say, but now i'm interested in the outcome. If you could document the the change out amount, add ratio, shift characteristics etc., maybe you'll help bust some myths.

 

[GaleHawkins]

Why have thoughts on this combo?

 

[KB2008X]

I don't have experience with the particular wrong fluid combination that you're proposing, but I have seen many transmissions screwed up by someone using the wrong fluid. For the life of me I don't see the advantage of draining fluid that is working and refilling with ATF+4 in a older, high mileage GM.

It would work for awhile, but ultimately will fail. How quickly is anyone's guess. If you want to keep the 2000 GM then use the best ATF available for it. In fact why even change the fluid if you're just going to put in the wrong ATF ? How about you sell the Mopar ATF+4 and use the proceeds to buy the right fluid ? Is there an auto repair shop that you do business with that you could work a trade with ? I'd bet you've had the ATF+4 for awhile now, so you probably paid less for it than it's selling for now. Someone will buy it for $1.00 or $2.00 off current retail and be grateful to get it. I think your solution to your quandary is a poor one considering the better options available.

Please reconsider the risk versus benefit equation.

 

[95busa]

Horrible idea.

 

[demarpaint]

Honestly I agree with the others. Put the fluid up for sale on Craig's List or try a few transmission shops and see if they'll take it off your hands. I would not intentionally try the wrong ATF on a hunch. JMO

 

[Hokiefyd]

Although Chrysler did replace earlier versions of Dexron with their own ATF+ series of fluids, the friction modifiers are quite different between them, and the clutch materials were modified in the transmissions commensurate with the fluid change. Many, MANY minivan transmissions failed in the late '90s because people put Dexron fluid in the transmissions, when ATF+2 or +3 should have been used.

I feel you have little to gain by using +4 in your GM transmission.

 

[Zaedock]

Stick with the Dex on this trans.

 

[bmwtechguy]

So the ATF+4 has less friction modifier than the Dex fluids? I thought it had more. Seeing as some of the universal type fluids can work for both, i cannot see how it would so quickly ruin the transmission as some here are saying. I am not saying i recomend it, but i cannot see how it is so bad either. I know that trans slips the torque conveter clutch quite a lot each lockup by design so that the operator does not feel it, and that is one of my dislikes on that tranny. That slip is unnecessary and not sure how the ATF+4 would do there...slip more?

 

[The_Eric]

Originally Posted By: bmwtechguy
So the ATF+4 has less friction modifier than the Dex fluids? I thought it had more. Seeing as some of the universal type fluids can work for both, i cannot see how it would so quickly ruin the transmission as some here are saying. I am not saying i recomend it, but i cannot see how it is so bad either. I know that trans slips the torque conveter clutch quite a lot each lockup by design so that the operator does not feel it, and that is one of my dislikes on that tranny. That slip is unnecessary and not sure how the ATF+4 would do there...slip more?


I agree. We need more facts and less speculation and feelings.

I was under the impression that +4 had more FM than Dex 3 as well?

The rash failures came from using a regular fluid like D3 in an autobox that required a highly friction modified fluid. OP is talking about using a highly friction modified fluid in an application which was in fact back spec'ed to another highly friction modified one.

Maybe Molecule will chime in and shed some light and facts?

 

[gregk24]

Only Dex in GM's only ATF+4 in Mopar, only ATF Z-1 in Hondas, stick with what is spec'd!

 

[bmwtechguy]

Or whitewolf....

 

[Zaedock]

I do not know the FM level difference between DexIII and ATF+4, but I do know they have different static and dynamic friction coefficients and that they are not compatible.

A quick check on the redline site revealed that they make two different products for Dex/Merc vs ATF+X applications.

Either way, go with the manufacturers specified fluid and not ATF+4 simply because you have some on hand.

My $.02.

 

[il_signore97]

I've got a bit of a sidebar to add to this conversation...

So the OP wants to use ATF+4 in a Dex 3 tranny. Now, I'm not sure if that's a good idea, but I have to look at the vehicles that I have cared for in the past and their history.

1996 Intrepid, 3.3L, 4-speed tranny, spec'd fluid was ATF+4
1997 Oldsmobile Achieva, 3.1L, 4-speed tranny, spec'd fluid was Dex 3
2002 Honda Civic, 1.7L DOHC, 4-speed tranny, spec'd fluid was Z-1
2002 Chev Venture, 3.4L, 4-speed tranny, spec'd fluid was Dex 3
2006 Mazda 6, 2.3L, 5-speed tranny, spec'd fluid was Mazda V

So there was an ATF+4, MV, Z-1, and a couple of Dex 3 trannies under my care, some of which I still own and operate.

All of these transmissions were treated to Amsoil Synthetic ATF (the regular version, not the ATL thin version) as recommended by Amsoil. All of these trannies worked either the same or BETTER after being switched to this premium fluid. Lots of people report the same kind of effect when using Redline D4, also an excellent fluid.

My Intrepid drove until 330,000 km when I sold it. Lots of trailer towing, only 2 drain and fills in its entire life with Amsoil. I did install a tranny cooler for the towing. It ran perfectly when sold - shifted like new. And this was supposed to be one huge problem child of a transmission. Never failed on me.

The Oldsmobile had 2 drain and fills with Amsoil and ran until 220,000 km when it was totalled in an accident. Ran perfectly before that.

The Venture has had several drain and fills throughout it's life with Amsoil ATF, and currently has almost 290,000 km on it. Runs very well, and is still used for towing my trailers.

The Civic had 2 drain and fills, shifted very well after the first change, and was sold with a perfect tranny 2 years ago. The rest of the car was a different story unfortunately

The Mazda 6 has had 2 drain and fills with Amsoil, and this is a known problem transmission (FNR5 from Mazda). It was shifting harshly when we bought it, as it never had a fluid change. The Amsoil cleaned up the shifting nicely, and I hope once I do a pan drop and filter change it will further improve.

So my point is that how can all of these so called incompatible fluid specifications be serviced by a universal fluid such as Amsoil ATF, and also provide me with such great results and I've stated above? I'm genuinely confused as to how a universal fluid like Amsoil or Redline could exist if the OEM fluids were really that vastly different. Is there something about Amsoil or Redline fluids that are just that good, or is there more overlap than we think with OEM fluids?

 

[Zaedock]

Originally Posted By: il_signore97
So my point is that how can all of these so called incompatible fluid specifications be serviced by a universal fluid such as Amsoil ATF, and also provide me with such great results and I've stated above?


Because it was purposely designed to meet multiple requirements. Obviously, the chemistry is going to be different than each individuals specification and doesn't mean that they themselves are interchangeable.

BTW, neither the OE or Signature series fluids have Dexron VI listed.

 

[il_signore97]

Originally Posted By: Zaedock

Because it was purposely designed to meet multiple requirements. Obviously, the chemistry is going to be different than each individuals specification and doesn't mean that they themselves are interchangeable.

BTW, neither the OE or Signature series fluids have Dexron VI listed.



I understand what you're saying, and I can appreciate Amsoil ATF being made specifically to cover multiple specifications from the ground up, but you have to wonder that for such a universal fluid to even be possible, the different specs and OE fluids can't be all that far apart from each other...

 

[Zaedock]

I wish I knew the specific differences. Although I've rebuilt several GM auto's when I was into drag racing, I'm an engine guy and specialize in Jeep now. Back when ATF+4 was being back spec'd for DexronIII Jeep applications (transmission, not transfer cases), I know of several friends who had issues with their AW4 auto's after switching. Even I stayed with Walmart Dex III for my kid's Cherokee.

Given their individual chemistry difference, I simply wouldn't risk it, unless the OP wants to be a test mule and try it out.

 

[Wilhelm_D]

Originally Posted By: Wampahoofus
After studying Chrysler's SAE paper 982674 my gut reaction is that it would be fine. Both fluids are nearly identical in terms of cold and hot viscosity, and perform very similarly in service (until the Dex begins to degrade). Backing that feeling up, Chrysler superseded many of their Dexron-II factory-filled units' fluid with the ATF+ series. In the early days of the A-604 they also claimed ATF+ and Dex-III were interchangable (though we all know how that turned out in the Chrysler transmissions).

Your logic strikes me as solid.

Chrysler stated when it came out that you could use ATF+3 with *all* older Chrysler transmissions, including the 727 and 904 series. ATF+3 and ATF+4 share the same anti-shudder and frictional characteristics.

The change from ATF+3 to ATF+4 was to a longer-lived Lubrizol viscosity index improver and an upgrade to the base stock and additives.

I also note that GM recommends Dexron VI, another highly friction modified ATF, for your application.

You should know in short order if the substitution works satisfactorily and can dump it if the results aren't what you wanted.

 

[keith]

Originally Posted By: il_signore97
I understand what you're saying, and I can appreciate Amsoil ATF being made specifically to cover multiple specifications from the ground up, but you have to wonder that for such a universal fluid to even be possible, the different specs and OE fluids can't be all that far apart from each other...


Universal ATF manufacturers have satisfied themselves that the fluid won't immediately blow up your transmission. Maybe it won't shift as well, shift better, wear quicker, wear slower, but whatever, they are happy to take your money and have calculated that it will more than cover any warranty claims. The universal will most likely have more or less friction modifiers than the original fluid, more for some and less for some. Seems to work ok for most people.

I have only two data points. Switched ATF+3 for Amsoil Universal in a Dodge Caravan. Transmission slipped badly. Drained it and put in ATF+4. Worked great for the next 150K miles until we sold the van. Switched SP-III for Amsoil Universal in a Hyundai Elantra. Transmission slipped more than before. Drained it and put in ATF+4. Works great, now at about 100K miles on the ATF+4.

Will ATF+4 work in place of Dex3? Who can answer that? I don't believe there is a definitive answer.

 

[440Magnum]

You're always safest sticking with spec...

However it seems that the requirements gap between Dex and ATF+4 is not as wide as it once was. I know a person who's conducting a personal test using Dex VI in an old Mopar 41TE (the most picky of the picky). No problems at 10K miles, no TCC shudder, etc. But that's not a recommendation to swap

And I certainly wouldn't use +4 in anything spec'd for DexVI. DexVI is just a far better (newer) fluid with much lower oxidation, volatility, additive degradation rate, etc.