Transfer case rear housings

[coheed]

@eaglescout526 Here's some pics I took today and some I grabbed off the internet. I was wrong, only the speedo gear housing is the same from the 231 to the 242.

 

Np228

 

Np242

 

Np207

 

Here it's obvious that the tail housing couldn't be swapped as that bulge on the right side of the housing is open for fluid to pass through presumably. 

 

 

Np231

 

So, as we know the speedo gear housing is the same in pretty much all the transfer cases aside from the 207, but the threads are the same on the 228/231/242 and the 207 housing. So, obviously any cable that'll attach to one will attach to the other.

 

 

22 hours ago, eaglescout526 said:

….of course…thanks AMC. 
 

Now I want to hunt a 231 case end and see if that will bolt to the 207 and would help eliminate problems with lifts while using a 207

If the only problem is the speedo gear TH350 gear are readily available and are the same size as the 207 ones. You can even get full kits with a variety of gears, the corresponding gear that goes on the output shaft, and a new housing TH350 Master Speedometer Gear Kit 7 8 9 10 Drive 17 18 19 20 21 22 Driven | eBay

[89 MJ]

Here's a neat website talking about some of the different transfer cases, along with the applications for them:

http://www.n0kfb.org/homepage/amc/tech/transfer_case/swap/index.htm 

 

The website is about swapping the transfer case in an Eagle, but it does a really good job with explaining the different transfer cases. I wish it made note of spline count because NP119, 129,219, 229, 228, and 128s are all 23 spline to the best of my knowledge. Here's the part I found fairly relevant to this conversation. The rear half of the case can be swapped or the tail housings can be swapped with drilling and tapping new holes. 

Quote

The other modification is to the transfer case rear output shaft housing. Or actually, to the rear of the case. If you lay your old and new transfer case out side by side, and look at the location of the speedometer hole, you will see that the Eagle output shaft housing is rotated about 30 degrees counter clockwise with respect to the Jeep case. This is necessary so that the Eagle speedometer cable will clear the floor. You cannot use the Jeep transfer case housing as is, as t he cable will break (ask me how I know). You cannot just change the output shaft housing, it is identical, the difference is in the rear case half.

You have three options

• Split your old case in half, split your new case in half and swap the rear case halfs. Its not as painful as it sounds, but there you need to be careful. If you choose this route, first remove the tailshaft housing and speedometer drive. Then remove the bolts that hold the case half together. When you split the case, hold down on the output shaft, if it comes out with the case half, you are going to have some roller bearings fall out. Not lethal, but easiest if you hold the shaft in. Carefully review the old and new case halfs to see that they are identical. On the 129 to 229 swap we did, we drilled out one hole oversize from the 129 case to match the 229. It may not have been necessary. One word of caution here!! Be very careful when your working inside the case. There are hundreds of bearings waiting to fall out and incapacitate your new transfer case. Ask me how I know!

• Drill and the Jeep transfer case back half to relocate the output shaft housing. This is best accomplished if your remove the case half as above. On the 219 case I prepared, the bosses for the other set of holes is there, you need to drill and tap. On the 229 case I did, the holes were already there, but were not tapped. I would strongly recommend that if you choose this option, you remove the case half, so you can align yourself properly before drilling. One wrong move and there is a hole in your new case.

• The third option is to re-drill the output shaft housing to relocate the housing. This option sucks, cause you can only reuse 5 holes, instead of 6. I did this on my first swap cause the case was already installed before I realized the problem of the speedometer gear interference with the floor.

 

Some folks have suggested that you can avoid this problem all together with a 90 degree speedometer cable adapter, but I have no firsthand knowledge as to whether this works.

Of these options, the first is the easiest for the do-it yourselfer, but it does require that you take apart and disable your old 119, 129, or 128 case. I’d rather keep mine whole as a spare.

So, if you have adapted your new case with the proper yokes and relocated the tailshaft housing all that’s left to do is re-install.

Reinstallation is simply the reverse of removal. No really it is, it helps again to have a friend who can help you get the case lined up. Some of the early 119 and 219 cases use 10w30 motor oil for lube, some others use automatic transmission fluid (dexron III).

Again, as mentioned previously, the 207 and 231 will require additional mod’s to either the driveshaft or the output shaft to mate up with the Eagle stock hardware.

 

 

[eaglescout526]

Hey. We went in expecting results and by damn we still got some results! And I had a feeling that speedo cable end was the same. Be rather odd to have a unique end for the 207 but everything else is standard. Really out of AMCs wheelhouse to do that on the waning years. 

[coheed]

20 minutes ago, eaglescout526 said:

Hey. We went in expecting results and by damn we still got some results! And I had a feeling that speedo cable end was the same. Be rather odd to have a unique end for the 207 but everything else is standard. Really out of AMCs wheelhouse to do that on the waning years. 

Are there other problems that come with the 207 I don't know about? I mean my speedo has been inaccurate since I bumped to bigger tires, but it's better with the 3.55 to 4.10 swap, other than that I've had no issues and my truck is lifted and the aforementioned. Though there may be issues with the 207 in the XJs I don't know about.

[eaglescout526]

As far as I know, the 207 is just an older version of the 231. Guess a quick Google could say if there’s any other issues with the 207. But with me, I haven’t seen or felt any issues. 

[eaglescout526]

Not much bad about it honestly. Just was replaced by the 231. 
 

Though I did find that GM used a version of the 207. 207C. C meaning Chevy probably. 

[89 MJ]

7 minutes ago, eaglescout526 said:

C meaning Chevy probably

Can confirm. GM also used an NP241, which was the NP241C. But they also used an NP261HD and NP261XHD in 2500 and larger trucks because GM in the early 2000s was weird I guess. Dodges were D and Fords were F.