Dodge transfer case - ATF+4 or ?

[Short_Bus]

Hello folks,

I have a question about the transfer case in my '05 Dodge Durango. The case is an NV244 which is full time awd but it as has a selectable hi/lo range like a traditional 4x4. The AWD isn't a clutch type system, it works more like a rear end and divides power via a gearset.

The manual calls for regular ATF+4 like the transmission. I changed it last weekend but used Mobil 1 multi vehicle ATF instead. I figured Dodge just called for the ATF +4 just to simplify things since it was already using it in the transmission. I don't think the transfer case is particularly sensitive to type of fluid the way a transmission may be. My understanding is that the fluid is just providing a lubrication bath as opposed to the a hydraulic pressure it is subject to in the transmission.

Of course, now I am second guessing myself. Comments anyone?

 

[Panzerman]

What did your Transfer case fluid look like? I drained and changed mine at 26,000 and it was nasty. It was so dark it was almost black. I used Valvoline Full syn. Atf+4. I changed the Transmission filters and fluid too, but it was still bright red. I was surprised at how dark the Transfer case fluid was and the manual said I could have left it in till 60,000. I heard the ATF+4 has more lubricancy than the rest of the transmission fluids, other than that Iam not sure.

 

[zrxkawboy]

Originally Posted By: Short_Bus

The manual calls for regular ATF+4 like the transmission. I changed it last weekend but used Mobil 1 multi vehicle ATF instead. I figured Dodge just called for the ATF +4 just to simplify things since it was already using it in the transmission. I don't think the transfer case is particularly sensitive to type of fluid the way a transmission may be. My understanding is that the fluid is just providing a lubrication bath as opposed to the a hydraulic pressure it is subject to in the transmission.

Of course, now I am second guessing myself. Comments anyone?


I agree w/you 100%. Our Libby's case got a parasynthetic Dex/Merc, and it's just fine. Now the trans, on the other hand, only sees ATF+4.

 

[tomcat27]

You are correct in your assumption. The "special" part of ATF+4 is the friction coefficient which is important in the Tranny because the clutches are controlled electronically and for a smooth shift. no such components in the xfer case. Besides, New Process makes xfer cases for multiple mfrs. the older NP gearboxes called for Dex 3.

 

[Zaedock]

Originally Posted By: Short_Bus
I changed it last weekend but used Mobil 1 multi vehicle ATF instead.


I'm running the same fluid in my Wrangler's NP231HD (1/2 ton Dodge). It seems to work well and I have peace of mind if I flat tow when it's cold out.

 

[virtual]

atf+4 is fine, I would just suggest to extend your differential breather, I have seen lots of tcasse failing for such a small issue ,make sure they are there and long enough to don’t get any water in them. Since it’s a truck most of people wont slow down for a simple puddle of water.

 

[gomes512]

If your sure there aren't any clutches then pour in whatever. In the summer I run a syn 10w-30. In the winter I pour in whatever trans fluid I have leftover. Can't say I've ever seen any flakes or debris come out.

 

[deeter16317]

Originally Posted By: Panzerman
What did your Transfer case fluid look like? I drained and changed mine at 26,000 and it was nasty.



Mine drained purple...and was NOT ATF!! (and that was the OE fill). I want to say it was what the GM boys refer to as "grape juice"?

 

[deeter16317]

If you look at some of the original "specifications" for the NP2XX line of tcases, they originally spec'd Dexon II (two, not three) and those internals have not really changed since then. They use what the manufacturer has on hand...in the case of Chrysler, they use the ATF+3 and ATF+4.

I ran (until 2k miles ago) Royal Purple SynchroMax in my NP271 (Dodge 2500/3500 tcase)...used it for over 120k without any issues. Will probably switch back during the next run.

Most likely any synthetic ATF fluid will work, the main thing is that it gets changed frequently (no filter on a tcase).

 

[Short_Bus]

Thanks for the input all. I am feeling ok about it now. From what I have read, the NV244 has a planetary gear set up for distributing the power front and rear in awd mode - so no clutches.

It has 46k miles and I presume it was never changed (I got it at 30k). I would describe it as red with a hint of brown. I didn't think it looked too bad. I understand ATF+4 will naturally turn a little brown with use and the color shouldn't be used as an indicator of its condition.

On a related note, I didn't notice any kind of gaskets on the plugs or the case. I just cleaned them off and stuck them back in. Is there anything there to stop it from leaking or do the threads seal it adequately? So far after about a week, I don't see any leaks.

 

[deeter16317]

The threads adequately seal it...they are tapered.

If anything, I add a dab of never-seize to the plugs as they tend to lock in place due to the steel plug in an aluminum case. Make sure you always pull the fill plug FIRST before atempting to remove the drain...that way if the fill is seized, you don't drain the fluid and have no way to fill it back up.

The transfercase is one thing I change fluid in quite often...typically every oil change or every other oil change (15k to 30k). There is no filter and only a small volume of fluid...not that there is a whole lot going on as long as the majority of time is in 2wd.

 

[D-Roc]

Originally Posted By: tomcat27
You are correct in your assumption. The "special" part of ATF+4 is the friction coefficient which is important in the Tranny because the clutches are controlled electronically and for a smooth shift. no such components in the xfer case. Besides, New Process makes xfer cases for multiple mfrs. the older NP gearboxes called for Dex 3.


Sort of off topic, but this brings up a a question I have with regards to ATF+4. Understood, it's importance with friction coefficient in an automatic transmission, but what about a manual (like the current Dodge models which use ATF+4 as a lube?
I've just often wondered why an oem recommends ATF in a manual...do atf's have the required ingredients to satisy most manual transmission requirements? Or is it just like the TCase thing, where it just needs a good quality fluid?

 

[ledslinger]

D-roc- I have wondered the same about ATF in applications without clutches, where it only requires a portion of the lubes designed features. Many applications only require the lubrication, cooling, and anti-foaming features of ATF, with friction coeffiecient aspects possibly being immaterial.

To me this implies that manual transmissions that spec ATF, may have great flexibilty in possible lubricants. There is little compatibility with mechanical components (except synchonizers)to consider, with the main factors being antiwear, and shift quality.

A manufacturer may choose a particular ATF for a manual tranny because it is the one used in their automatic transmissions. Another type of ATF may be better.

 

[deeter16317]

Originally Posted By: ledslinger
D-roc- I have wondered the same about ATF in applications without clutches, where it only requires a portion of the lubes designed features.



Some manual transmissions have synchronizers that are clutch-like material. I believe some of those may need the friction-thing.

With that being said, I can't imagine a synchromesh fluid or manual transmission fluid working in those applications.

 

[ledslinger]

Deeter- I referenced sychronizers in the second pargraph.

 

[deeter16317]

I was just elaborating on the fact some synchronizers are not brass.

 

[ledslinger]

I wonder if the friction coefficient of various ATF's in manual trannys make a difference with brass synchros.

 

[deeter16317]

Not sure...

I believe the NV5600 (the older Dodge 6-speed) uses brass synchronizers, but it specifies synchromesh.

The NV4500 (the older Dodge 5-speed) uses "carbon fiber" synchronizers and uses GL-4 80w90 (but a synthetic 75w90 works well too).

I'm not sure what the G56 (newer dodge 6-speed) has for clutches (it specifies ATF).

 

[VNTS]

I use Amsoil MTF in my NV242 cases.

On the Jeep boards there is a guy rebuilds most of the Jeep Transfer (Transfer Cases Unlimited)cases and recommends synthetic 5w-30 oil for his warranty since the oil will not shear like the ATF. I have used the MTF for a couple years, prior to that I used the Amsoil ATF. I drain em every couple years since it is so easy.

 

[deeter16317]

Originally Posted By: VNTS
I use Amsoil MTF in my NV242 cases.

On the Jeep boards there is a guy rebuilds most of the Jeep Transfer (Transfer Cases Unlimited)cases and recommends synthetic 5w-30 oil for his warranty since the oil will not shear like the ATF. I have used the MTF for a couple years, prior to that I used the Amsoil ATF. I drain em every couple years since it is so easy.



Motor oils are typically not as shear stable as a gear oil/fluid. I assume your talking about 5w30-weight MTF?

Using the MTF is similar to the use of SynchroMax...they are both manual transmission fluids.