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The Uppity 12v Guy
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Discussion Starter #1 (Edited)
There seems to be enough interest for me to document my progress as I jam a G56 into my '95. There are other write-ups around for G56-into-2nd gen swap, but there is no definitive guide one getting one set up in a 4x4 and as far as I know, there isn't one that has the old transmission being an automatic. Most of the auto-to-manual stuff is the same whether the new trans is a G56 or an NV, but we'll be covering all the bases at once here.

The parts I don't have for this project are in the mail, and I will commence with tearing my truck apart tomorrow after work.

Lets start with a parts list. What do you need?


  • You need a G56 transmission and shifter.
  • You need a clutch.
  • You need a 29-spline input for your transfer case, or a transfer case from behind a manual transmission.
  • You need pedals, a shifter boot, and steering column plastics out of another 12v. This is salvage yard stuff.
  • You will need to do some fab work on the crossmember and the transfer case shifter linkage.
  • You will need to have driveshaft lengths altered.
Resources:

Here I will list all the technical resources I used for this swap, and will add any pertinent ones I find along the way or after the fact.

Component information:

  • G56 FSM. This is an excerpt from a 4th gen Ram FSM, and gives very detailed instructions for service and overhaul. You need to sign up to ScribDB, but it's free and instant access.
  • Also, CF member toms73novass has a G56 rebuild thread here. I found it very helpful.
  • Your truck's FSM. I used this primarily for my transfer case, but you should have one anyway. Available in the stickies.
  • Also, CF member 3.9 islander has an NP241DLD rebuild thread here. This was also very helpful.
Other swap threads:

 

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The Uppity 12v Guy
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Discussion Starter #2 (Edited)
Transmission:

Information on the G56 is just a Google search away, so I won't clutter this thread with such available information. What is important here is that there are some very easy to correct differences between the 2wd and 4wd transmissions. The most important is the output shaft seal. The 2wd seal seals against the output yoke, and the 4wd seal seals against the output shaft itself. If your donor is a 2wd, you will need to change this out because without an output yoke, the seal has nothing to seal against. I would recommend replacing both input and output seals anyway... the trans is out of the truck, what better time to do it?

The other difference is on '05 and '06 2wd transmissions, the rear mainshaft bearing snap ring is omitted because, according to TSB 21-006-06, "the output yoke retains the bearing." If your donor is an '05 or '06 and a 2wd transmission, make sure you have a snap ring here. If you don't, get one. All 4wd transmissions have this snap ring, and my '08 2wd transmission already has this snap ring, so I'm going to assume that they made them standard somewhere along the line. Honestly, I'm not sure why the bearing needs a snap ring. It's pressed into place against a step on the mainshaft, and the cup pressed into the case retains it from moving the other direction. :confused013: But the Mercedes goons say we need one, so I guess we need one.

My donor trans was pulled from a supposedly rolled '08. The guy I got it from said over the phone it was in good shape. Turns out he lied. Now, he may have been mistaken but he also conveniently omitted the part where the factory flywheel exploded and sent chunks through the bellhousing. And the part where one hole was patched with JB Weld. He let me discover this for myself after I'd spent an entire day driving 300 miles to check this thing out. I also noticed a very slight "sticky" spot at each revolution of the input shaft. That one could have been easily missed, but there's no way he didn't know about the bellhousing damage. At any rate, the trans turned over in every gear and the price was right, so I brought it home.


Here is is. Bell housing damage is visible in this picture, there's a hole about the size of a nickel in the middle of the bell housing right behind a gusset about halfway up. There was another hole about the same size, down low on the passenger side. This one was filled with JB Weld (which made weld prep REALLY fun). Then there were two places where something hit hard enough to crack it all the way through, but the chunk did not penetrate. Quite a few of the internal gussets were also cracked or chipped.


The gaping maw of the bell housing. One hole is now easily seen, the part on the left where light is shining though. The blob of white at lower left is the JB Weld

After the line of bull this guy fed me, there was no way in hell I wasn't going to thoroughly check this thing out before installing it. Disassembly was a breeze once I got a T60 socket to remove the 5-6 shift fork pins. The transmission has a very straight forward design, almost elegant in it's simplicity.


Here is is, 'sploded. Once again you can see one of the holes. Countershaft is standing up, mainshaft is on the towels.


The sticky spot on the input shaft turned out to be 6th gear missing a few teeth. Good thing I found it because it would have let go entirely the first time I got on it hard in 6th.

Once I had the case apart, the bellhousing damage was easily welded up. I am no stranger to welding cast aluminum, and like always I chose to TIG it. In repairing this damage, I found that the case casting seems to be of very high quality. Porosity was very minimal and the alloy used responded surprisingly well to the welding. Keeping the heat down in the whole casting was the only challenge, but all that took was time. Pictures:


Upper crack & hole, outside.


Lower crack & hole, outside.


Lower crack, hole, and repaired gussets, inside.


Detail of lower, crack & hole, inside.


Upper crack & hole, inside.

I will also if course be changing the output seal to the 4wd one and will also change the input seal, just because. I will weld a fitting for my transmission temperature gauge onto one of the PTO covers. Everything else looks really good in there, and aside from a through cleaning, the only other "modification" I plan on is reinforcing the welds on the reverse shift fork. They have been known to fail, and after inspecting the welding job they did, I'm not all that surprised. Stress risers everywhere. :banghead: I can correct that tomorrow.

Clutch:

With the factory 47RH/NV4500 adapter, a standard G56 clutch will work with no problems. You will most likely want to do a single-mass flywheel conversion, and I recommend contacting your favorite clutch vendor (Peter at South Bend helped me out a lot). Let them know what you're doing, and what you need from the clutch, and they should get you squared away. There have been reported fitment issues between the starter and ring gear with a certain other adapter, I will have to look that up and edit the information back in later.

Transfer Case Input:

If you're coming from an auto, you need to swap out your transfer case input shaft or get a transfer case that came from behind a manual. The good news is all the Dodge manuals use the same spline count: 29. The bad is that if you are switching the input, there are still 2 shafts to choose from. One uses a wide bearing, the other uses a narrow bearing. The good news is Quad 4x4 has very detailed tech notes on which one you need. Get the assembly number off your case tag and compare it against the tech notes for the two (QU10889 and QU10699) shafts to figure out which one you need. I also picked up a complete seal/gasket kit for my NP241 as you have to take the case pretty far apart to swap inputs, and mine was seeping anyways. I'll also inspect/replace any parts I find that need it. I'm not expecting much in the way of that, but you never know.

As far as transmission and transfer case parts, I had excellent service from Andy at Standard Transmission in Ft. Worth, TX. He spent a total of probably 45 minutes on the phone with me and was super patient and helpful while we made sure I was getting the right parts.

As far as pics, my phone camera recently got smashed so they'll either be crap photos, or I'll have to find a different camera. I'll get some pics tomorrow.
 

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This is why i will be buying a rebuilt transmission regardless if i use the NV4500, Nv5600 or G56.

Most people is saw used the Nv4500 adapter with a NV 5600 clutch.

Also will any Manual transmission TCase work from a 2nd gen Dodge, I would like to up grade to a DHD T case too bad I have an NP205 in the garage already
Problem is it's a 32 spline off a Chevy with the Muncie 4 speed with granny gear

Also the 2nd gen console fits pretty good. There really isn't a good way to bolt it down but its not going anywhere once its in. Theres a small gab between it and the dash, pretty unoticeable
 

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The Uppity 12v Guy
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Discussion Starter #5
I would love to see some pics of that console, Alan. And yes, any transfer case out of a manual Dodge has the right input. I edited the post to clarify that.
 

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The Uppity 12v Guy
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Discussion Starter #7 (Edited)
Edited previous post with pictures, and have some others from today's progress...

The reverse shift fork has been reported to fail. Drivers experience a loss of reverse, and it's because the plate on the back of the fork that actually impinges on the synchro has broken off.


Here is a close-up of one of the welds. This was all done by robotic TIG, and I assert that the programming was only one notch above lousy on this particular part. The other shift forks looked really good however. The left side of this weld shows a good example of where a crack would eventually start. The unwelded area of the joint focuses stress at the start of the weld. Enough stress and vibration and this unwelded area would act as a wedge, eventually splitting the weld.


Here's another. When welding, but especially TIG welding without filler (as this was) you don't want any part of the joint unwelded if you can help it.


Also, there were simply NO welds on the inside of the plate... :banghead:


...so I took the initative.


I also wrapped the welds completely around the joint area, so there is nowhere for a crack to start.

After I got home, I went to work on the truck. I started with the pedals. It didn't take long for this project to turn into a pain in the junk.

It could have been extremely straightforward, but some nimrod ran the lines for boost/fuel pressure gauges, the wires for the pyro, and the wires for the electric fans through the clutch master cylinder plug and bracket. :banghead:

That turned the 10-minute job of installing pedals into about a one hour job. And right before I was ready to push all the wires back through the firewall, I had to go and slice a finger open on my dominant hand. Brilliant.

However, it's a pretty simple job. Remove the e-clip from the drivers side of the pedal pivot pin. Push the pivot pin out the passenger side. Drop the brake pedal out. Slide the new brake and clutch pedals in one at a time, sliding the pin back to the driver's side. Put the e-clip back on. Hook the rod up to the brake pedal and put the clip on. Now readjust your brake light switch. When you install the clutch hydraulics, punch the rubber plug out of the firewall and hook up the rod. My clutch hydros are out of an '09, but the master locks into the pedal bracket like it was meant to go there.


However, now that everything's re-routed, it looks good having the right number of pedals there...

More tomorrow.
 

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I had a chance to get a G56 2wd for. $600 probably could've gotten it for $500. It had a stripped 6th gear.
Went with a used Nv4500 instead. Luckily for me the seller was honest. Nothing wrong.
 

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The Uppity 12v Guy
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Discussion Starter #10 (Edited)
Okay, today was spent plugging away at unhooking things. Nothing was pic-worthy... just driveshafts, cooler lines, TV cable, and skid plate.

The skid plate might pose a problem because of the crossmember mods. I'm not sure how upset I am about this though, the factory skid plate has always irritated me a bit because of how far it sticks down and how little impact protection it provides. At this point, I'm not sure it's even going back on. The transfer case doesn't stick down that far and I don't get into that gnarly of situations off-roading. If I decide to put one back on, I'll probably just make a new one out of 1/4" plate.

I also got a closer look at my transfer case shifter, and that part has the capacity to be a pain in the @ss. Reason being is I incorrectly remembered the shifter mounting to the cab, when in real life it's entirely mounted to the transmission. The "fab work" I thought I would have to do was just to accommodate for the longer length of the new transmission and possibly working the rod around it's girth.

After some research, it appears I need the shifter linkage out of a 98-02 Ram. That style mounts to the cab, and I found a thread where a guy used it and it apparently worked for him. I'm going to call my local wrecking yard Monday and see if they can hook me up. If not, I found another thread where a guy made a bracket on the side of the G56 that worked for him. Also, I learned the shift knobs for the transfer case and the factory G56 shifter are the same. Just different shift pattern inserts. Or, (I learned a cool word for them) "shift pattern escutcheons."

I also noticed the neutral safety switch while I was down there and realized I was going to have to do something with that. There are two wires coming out of my master cylinder for the clutch safety switch. I have always detested the "clutch in to start" crap, however, my wife's Subaru will kick cruise control off if you tap the clutch. I kinda like that feature. It appears the switch on the '09 clutch master works with minimal pedal input, but I haven't seen it in action so I don't know. Will the factory neutral safety switch on the 47RH deactivate cruise if continuity is made/broken?
 

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The Uppity 12v Guy
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8,133 Posts
Discussion Starter #11
I got some more work done today. I was only able to work on it for a few hours but I got most of the peripheral automatic components removed, and got the transfer case out. I was able to remove the oil-air cooler without removing my bumper. It was a chore but it beats the hell out of removing *my* bumper, especially with the way my truck is jammed into my garage.

I got some pictures of the bellhousing weld job and have edited them into post #2.

I also remembered one salvage yard was open today, so I scored a late 2nd gen transfer case shifter. Unfortunately, I think it's going to be easier to build a bracket off the side of the transmission's rear case and use the early shifter like that other guy did. The late shifter mounts far enough over to the side of the tunnel that mounting it will be very hard, because the carpet will NOT budge nearly enough to get sheet metal screws in where they need to go. It also mounts sufficiently flush with the floor that I think there might be a clearance issue with the boot. It might be different once I get the transmission out of the way and I can really mock it up, but that's what it's looking like now. I'll get some pictures tomorrow when I know more.

Before I dropped the transfer case, I got measurements of where the t-case output sat vertically in relation to the bottom of the frame rails and laterally (I guess, forward vs backward) relative to a brace on the bottom of the cab. I'm expecting the output to be about 2" further toward the rear, and will hack'n'fab the crossmember to achieve the same vertical height.

Tomorrow I have the entire day, so I'm expecting to get some major work done.
 

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Nice progress, ill see if i can slim jim that console in tomorrow, Somebody removed my Engine mounted transmission cooler, Dealer called it the torque converter cooler? :confused013:

Since it need that part for my truck and its an 800 dollar part not including all the lines i would need, and im not willing to risk spending the money on a used one. Ill go this route.

This guy used a G56 flywheel, Nv4500 adapter, same nv4500 starter and a NV5600 clutch
Dodge Cummins NV4500 to G56 - DONE! - Page 2 - Expedition Portal

Im missing why he didn't use a G56 clutch
 

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The Uppity 12v Guy
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8,133 Posts
Discussion Starter #15
Nice progress, ill see if i can slim jim that console in tomorrow, Somebody removed my Engine mounted transmission cooler, Dealer called it the torque converter cooler? :confused013:

Since it need that part for my truck and its an 800 dollar part not including all the lines i would need, and im not willing to risk spending the money on a used one. Ill go this route.

This guy used a G56 flywheel, Nv4500 adapter, same nv4500 starter and a NV5600 clutch
Dodge Cummins NV4500 to G56 - DONE! - Page 2 - Expedition Portal

Im missing why he didn't use a G56 clutch
That wasn't clear to me either. :confused013: Since the NV5600 and SMF G56 clutches apparently interchange, I'm wondering what the functional difference is between them. Perhaps the only difference is what you choose to call it?
 

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The Uppity 12v Guy
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Discussion Starter #16
I have a solid flywheel laying around somewhere (if I can find it)for one of these close to new shape If in need of one.
Thanks for the offer, I've already got my flywheel and clutch situation squared away. Alan might be interested though, he could save some coin when he gets rolling on this.
 

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The Uppity 12v Guy
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Discussion Starter #17
Alright. Mid-day break and the old transmission's out. I was hoping to have my goodie box from Standard Transmission before the weekend so I could get rolling on reassembly, but not receiving it yet has been a blessing in disguise.

The G56 still sits disassembled on my welding table. I will take advantage of that by putting the case halves back together with a few bolts, and mocking up as much as I possibly can with the empty case. The case is extremely light. If it weren't for balance, you could just about palm it into place behind the engine.

I'm hoping to get a good amount of work done on the crossmember and transfer case shifter, as well as make sure my clutch geometry is savvy (I'm using a franken-clutch that I got cheap, hope it all fits!) before assembling everything for real.
 

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The Uppity 12v Guy
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Discussion Starter #18 (Edited)
Today was very educational.

It started by removing the transmission.


With all sorts of room under there, I got a mockup of the late 2nd-gen transfer case shifter:



Basically, there's no way in hell it would work unless you were swapping to a 98+ console. In which case, it might save a lot of work for this swap, because the geometry of a bracket on the side of the transmission is going to suck. More on that later.

I learned I should replace my rear main seal. Any tips worth sharing?

Next, I threw my flywheel on. It was heavy:


I verified my starter engagement was correct.


Then I threw the rest of my clutch on. This was hands down the most physically grueling mechanical thing I've done in a while. This is a dual disk clutch, and while one disc was held in place-ish by the intermediate plate, I had to hold the other disc and the pressure plate with one hand, and try to align it enough that I could thread a bolt with the other. It was literally painful, but the only other option was to have those heavy things fall on my crossed legs which would have well and thoroughly sucked. Moral? Don't try to be stronger than the equipment. Get help.



Next, it was time for my pretend tranny to go in. I used a paper towel rubber-banded around the shift tower opening to keep junk out.


Putting it in was SO much easier than putting in a complete transmission. At this point I learned I needed a different clutch fork (zero free play :doh:). I pulled it off real quick and removed the fork, then put it back on. I found that the bellhousing bolts could be slightly longer with the G56 as the mounting ears are 1/8" thicker. I'm going to pick up some 1.75" flange bolts to replace all my old ones.


Next up was the transfer case. With my floor jack supporting the front of the engine, and the trans jack under the transmission, I was left with no other option but to "belly" it into position. This actually worked pretty well, it's a light transfer case and I was able to shove it up towards my knees to help jockey it into position. I found a ratcheting box-end wrench very helpful in tightening the nuts on the transfer case studs due to the way the mounting flange is gusseted on the G56.


I then tried to get the output shaft positioned at the same 4.625" above the bottom of the frame rails that it was with the 47RH, but the shift tower boss hit the cab before I got there. I decided to cut the floor out before proceeding. I used a 3" air powered cut-off tool. Worked great, even cutting through the carpet.


Next I figured I would mount the tower and shifter to verify that the shifter wouldn't hit the trans temp gauge on my lower dash. It was also a convenient time to spend a few minutes in the driver's seat and absorb what it would be like to FINALLY have a manual again. There were no clearance issues, by the way.


After raising the transfer case to the same height that the output was at with the 47RH, it was time to get some measurements. I determined that my rear driveshaft needs to be longer by 2.563", and the front shortened by the same. I was expecting to need to shorten the rear driveshaft, but I didn't realize just how long the 47RH is until I had it out and on the floor.

I next went to figure out what my crossmember was going to need. I took the old transmission mount and took the two halves apart. The part with the rubber block bolted right to the mount provision on the G56, and the bolts from the transmission mount were even the right thread! I attached it to the new transmission and went to put the crossmember back in. I quickly found that the transfer case was in the way for reinstalling it. I supported the transmission and reverse-bellied the transfer case back out of the truck. Once I got the crossmember back in place, I realized the modifications were going to be fairly easy.


The mount block just hangs off the back of the crossmember.


All I need to do is build a little platform, the surface of which needs to be .875" tall from the very bottom of the crossmember (note, this dimension should be .375" tall, see post #67). The platform needs to extend rearward 1.125" from the rear-most edge of the crossmember. It needs to be the same width as the rubber block (didn't measure that yet, just scribed marks on the member).


The respective centers of the holes for the studs need to be 1.938" from the rear edge of the slots, and are in line with each slot (as this mount originally went in those slots). The studs are an M10 thread so 7/16" will work well for the holes.


For the exhaust mount, I'm just going to cut the exhaust mount off the other part of the old transmission mount, slip it on the peg, then weld a small piece of strap to it which will be welded to a piece of angle, which will then get a nut welded to it so I can run a bolt up from underneath through the hole visible in the crossmember. It always irritated me that that exhaust support was tied into the transmission mount. Now they'll be separate and I can chill out about it.

I will need to hammer the floor up a tiny bit for clearance. The little cylindrical thing at center right is a boss for a shift fork detent, and it's touching the cab here. It's just barely rubbing, one solid whack should give it some room and not be visible from inside. Other than this, I don't need to hit anything else anywhere for clearance.


Here are a couple pictures of where the transfer case shifter needs to go. Basically, the lever's going to have some jankey bends in it to go through the center of the slot because the actual assembly needs to be over a ways to the left. If this were a 98-02 truck, or you were modifying your truck to use that shifter and console, you probably wouldn't need to modify anything. Maybe just bend the shift rod a little to clear the transmission, but it would be very easy to get it hooked up.


Sorry about the glare. That's my shattered camera lens messing up my ch'i.


That's as far as I got tonight. I'm waiting on transmission and transfer case parts, I need to get and install a RMS, I need to get a different shift fork, and I need to make some stainless plugs for when I delete my oil-water cooler. Plus all that other fab I talked about. :rof
 

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The Uppity 12v Guy
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Discussion Starter #19
Got my goodie box from Standard Transmission today, and it looks like a local CF member is going to throw me a bone on a clutch fork.

I don't think I'm going to be getting anything done tonight, but things are slow at work so maybe I can coerce my boss into letting me rebuild my transfer case during the lull.
 
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