NV 273D Transfer case rebuild...

[GI Joe]

Going to be tearing my Xfer case out for a total rebuild this weekend.
I believe my chain got stretched when my trans imploded and ate 6th gear a few weeks ago..(not having much luck with this first month of owning this truck...:roll eyes:

I've watched a few vids and it seems straight forward... I have all the new bits here, and just wanting to make sure there isn't any super insider info I need first...

Hopefully my service manual CD shows up quick tomorrow, so I can get torque specs for the case halves..

Any words of wisdom/advice from lessons learned??

Thanks y'all!

 

[GI Joe]

Wow, nothing?? No advice? Not even an off topic remark like most threads have?

Sheesh, y'all are a tough crowd! Lol

Got it all rebuilt, new bearings, guides, seals, chain, and oil pump! Gave it the full Monty..

Two fresh qts of Amsoil ATF on the shelf, ready to go in!

Waiting on one final snap ring to come in to the stealership tomorrow, then I can glue the tail cone on and re-install..
The snap rings in there are Heavy duty, and my Napa snap ring pliers fell a little short of the job. For posteritys sake, I'll be sure to note what pliers I end up getting to handle this job well. Aside from a 10mm and 13mm socket to get the case bolts out, the snap ring pliers are all that's needed inside.

Overall, a 3/10 on difficulty scale... I'd do it again, no worries!

 

[cerberusiam]

Leave the ATF on the shelf for use in power steering or auto trans, it is crap in a t-case. Use either SyncroMesh or a mixture of SyncroMesh and the Delvac 50 wt the G56 needs. It just has to be thin enough for the pump to pick up in your coldest temps.

 

[GI Joe]

Can you expand on "it is crap In a t-case"?

I'm all for taking care of my truck, especially with this one all fresh, but need more info before I'm sold...

Isn't synchromesh a bit thicker than ATF? Wouldn't this overtask the new pump in the T-case?

Always seen/heard of using ATF, never anything else.. You've peaked my interest!

 

[cerberusiam]

ATF+4 has a lof good properties, just not the best for gears and bearings in a t-case. It is too thin and gets thinner when it is hot so it doesn't stay on surfaces as well. If the lube doesn't maintian a good coating you get wear becasue it is metal on metal. The bulk of the use in an auto trans is cooling and viscosity for maintaining pressures, not what is needed in a gear scenario. Dodge cheaped out on all the case in the drvie train and just specced ATF+4 becasue on paper it looks good, in practical application and hard use it doesn't perofrm as well. The only reason the pump is there in the tcase is because the lighter lubes will not stick well enough so they need a pressure feed to lube properly.

Quite a few have found the SyncroMesh and\or a mix with 50 wt transmission oil to be a good substitue for rigs that tow a lot. You can't run the heavier fluids but the 30-50 wt seem to work quite well if you don't live where the temps get real cold. Would be a little dicey -20 to -40 but as long as the lows are generally above 10 degrees you likely would not have any issues. In that case you could run straight syncromesh which is something like a 30 wt oil.

 

[GI Joe]

Sounds logical to me! I'm sold! Lol

Thank you for the tip!

Would you happen to have the torque specs for the tail cone and t-case halves? (My manual hasn't shown up yet... )

 

[GI Joe]

Alright, I got this project done... Also replaced fluid in both diffs while I was at it..

Case halve torque was 20-25lb ft... Nice n easy! Manual showed up the day after I reinstalled the tCase, and learned I reversed one piece and it was stuck in 4wd.... �� Complete tear down and rotate that one ring, and put it All back together again...�� Did the second round in just under 4hrs from shutting the truck off after learning of the stuck in 4wd condition...
Not a bad job at all. I got my rebuild parts from Drivetrain.com, in NV... Quick shipment, and an Awesome phone tech support line. I probably annoyed that fella with my calls, but I was trying all I could to not have to do a round 2 tear down.... He knew exactly what I'd done, and wished me luck on the second go'round!

All in all, a relatively easy project. The noises are gone, and I feel much better knowing the 187k mile bearings are replaced with fresh.. A few of the old ones were Very growly, and had some play in them... Definently time for fresh!
So, don't be scared to handle this when it comes up! A ratchet set, some BIG snap ring pliers(not the things from the parts stores), plenty of towels and I used brake cleaner to blast out the case.... That's it... 2qts of fresh fluid, Syncromesh was suggested above and that is what I went with... And document the orientation of all the bits you take out!! ��

 

[Ozymandias]

Leave the ATF on the shelf for use in power steering or auto trans, it is crap in a t-case. Use either SyncroMesh or a mixture of SyncroMesh and the Delvac 50 wt the G56 needs. It just has to be thin enough for the pump to pick up in your coldest temps.

In Jeep-Days I used 5W-50 Mobil ONE fully synthetic Engine Oil because it was easy to get.

Would this be also a good Oil for the 273? Especially in cold areas?

 

[cerberusiam]

In Jeep-Days I used 5W-50 Mobil ONE fully synthetic Engine Oil because it was easy to get.

Good question. Theoretically it should work fine, but, no way to know for sure until it is tried and run for several 100k to see the results.

 

[Ozymandias]

Good question. Theoretically it should work fine, but, no way to know for sure until it is tried and run for several 100k to see the results.

I think I'll go this way, 50 Gear Oil is hard to get here, even impossible.

The 249,242,231 NVs worked fine with this oil, and what is different between them, only the size?

 

[455kcummins]

Hey Gi joe. Great job on getting it going. I'm working through the same thing. Can you explain the part you had in reverse or post a pic. I'm have the same issues. .. no 2wd. Thank you.

 

[GI Joe]

Hey Gi joe. Great job on getting it going. I'm working through the same thing. Can you explain the part you had in reverse or post a pic. I'm have the same issues. .. no 2wd. Thank you.

Hopefully these pics will help future events!
Here is the orientation at the initial point of opening the case. There is a short side and long side to this gear. This is the selector in question, that engages the chain sprocket to engage the front drive shaft(selects 4wd)..
#ad


Here is a view of post rebuild, with the selector in the WRONG orientation. Hard to tell with these two shots, the long and short side of the gear..
#ad

 

[DFerverda]

Hey, great job. Thanks for finishing up the post and the pic's. Did you add the whole kit, chain, gears and all or just the bearing and seal kit? What was your old transfer doing, just growling or did it quit altogether?
Thanks Dirk

 

[seafish]

Cerbusiam, New Venture specs and continues to recommend ATF+4 in the NV273 series transfer cases.

I will be running either Delvac 50 or Amsoil MTG in my G56 when I so a fluid change coming up at 100k.

For reasons of simplicity, I was hoping to ALSO run the same lube oil in the tc, but from what I can tell that is NOT recommended..do you have any further insight our experience into using fluids OTHER then the factory recommended ATF+4 in the NV273 ??

 

[GI Joe]

Hey, great job. Thanks for finishing up the post and the pic's. Did you add the whole kit, chain, gears and all or just the bearing and seal kit? What was your old transfer doing, just growling or did it quit altogether?
Thanks Dirk

Old one was growling quite a bit, but still worked just fine. This is my road rig, so any extra noises after a few hundred miles really wears on my bad hearing... I suspected my Chain was stretched, after my trans implosion incident on the interstate... But it was just slightly "longer" than the new one.. Probably not needing replacement, but I did the whole kit 'n' caboodle.... Seals, bearings, nylon guides, chain... The full kit! No reason to cheap out once you're in there!

 

[cerberusiam]

New Venture specs and continues to recommend ATF+4 in the NV273 series transfer cases.

The only reason they did that was to share fluid with the G56 and eat their own dog food. Use the same fluid as the G56. If you are where it is warm most of the time you probably get away with using the straight 50 wt fluid. If it gets cold where you are, I mean down into single digits and below for weeks on end, cut it 50-50 with Syncromesh.

 

[seafish]

The only reason they did that was to share fluid with the G56 and eat their own dog food. Use the same fluid as the G56. If you are where it is warm most of the time you probably get away with using the straight 50 wt fluid. If it gets cold where you are, I mean down into single digits and below for weeks on end, cut it 50-50 with Syncromesh.

LOL…of course that is EXACTLY the reason I want to run the Delvac 50 or Amsoil MTG in BOTH the G56 and NV TC…to minimize the stocking of different fluids.

How many trucks do you know of are running the Delvac 50 or other lube in the NV TC??

 

[cerberusiam]

The guy in NM has a fleet he transports with, I think he said he was switching all his to at least a 50-50 mix of Delvac and SyncroMesh. He has reported no problems yet.

I have been running Syncromesh in mine for the last 150k with no issues. I am switching to 50 wt when I change here shortly.

 

[brods]

The only reason they did that was to share fluid with the G56 and eat their own dog food. Use the same fluid as the G56. If you are where it is warm most of the time you probably get away with using the straight 50 wt fluid. If it gets cold where you are, I mean down into single digits and below for weeks on end, cut it 50-50 with Syncromesh.

The only reason?? New Venture / New Process has been spec'ing ATF in tcases for at least the last 30+ years. It is not something Dodge did when the G56 came out. You know better than to say something like that.

 

[cerberusiam]

I think you severely underestimate the corporate bean counter strategy. It has been known for 30+ years Dodges spec for ATF was totally inadequate for certain usage scenarios, and, since New Venture was primarily a Dodge product line it is no wonder how that spec got invented.