JK Dana 44 in a CJ7

[Ultrunner]

I have an AMC20 I’m my 85 CJ7 and realized the cost and effort to rebuild and upgrade might be more than just finding a better axel all together. I found a rear Dana 44 out of a JK for a great price.

Just pooling the experience base here for advice on doing this swap. Is it worth it? Not sure how much effort other that new spring perches and possibly new master cylinder. Thanks in advance.

 

[gert]

The later Jeeps have a different bolt pattern I think the JKs are a 5 on 5 the CJ has a 5 on 5.5, you will also need to find out what the width of that JK axle is I’m pretty sure it’s wider than a stock CJ, your driveshaft will have to be modified and you will have to adapt the parking brake to your set up plus what you mentioned about the master cylinder and curing off the 4 link brackets and shock mounts. Do you know what the gear ratio is?

The AMC20 gets a bad rap from its 2 piece axle shafts and thin axle tubes which are solvable
And it would be a pretty good axle after that just takes money

Sent from my iPhone using Tapatalk

 

[Ultrunner]

The later Jeeps have a different bolt pattern I think the JKs are a 5 on 5 the CJ has a 5 on 5.5, you will also need to find out what the width of that JK axle is I’m pretty sure it’s wider than a stock CJ, your driveshaft will have to be modified and you will have to adapt the parking brake to your set up plus what you mentioned about the master cylinder and curing off the 4 link brackets and shock mounts. Do you know what the gear ratio is?

The AMC20 gets a bad rap from its 2 piece axle shafts and thin axle tubes which are solvable
And it would be a pretty good axle after that just takes money

Sent from my iPhone using Tapatalk

Thanks Gert, yeah I did notice that the bolt pattern was different. Not sure the labor and cost to adjust that, plus I'd have to modify my front axle to match the gear ratio (seller reported 3.73).
I haven't been able to find tubes for the AMC20 , I know that the one-piece kit is about $300. Adding disc brakes in about another $500-$600. Almost a grand, but maybe the modifications required to the Dana will amount to about the same.

 

[gert]

Thanks Gert, yeah I did notice that the bolt pattern was different. Not sure the labor and cost to adjust that, plus I'd have to modify my front axle to match the gear ratio (seller reported 3.73).
I haven't been able to find tubes for the AMC20 , I know that the one-piece kit is about $300. Adding disc brakes in about another $500-$600. Almost a grand, but maybe the modifications required to the Dana will amount to about the same.

Yep sounds about right, you can truss the back of the AMC20 easier than you can change the tubes tho

Totally up to what you want to do

A Ford 9 or 8.8 is also a really popular swap


Sent from my iPhone using Tapatalk

 

[jp360cj]

The JK rear is actually a pretty good axle. It has a larger ring gear than the older D44s (8.8 or 8.9 vs 8.5") and disc brakes. Not sure of the housing/shaft specs. They are "full width", ~65", which is ~12" wider than a WT CJ rear. And as mentioned, the 5 on 5" lug pattern.

Being so wide, you'll either spend a boat load to have it shortened, or have to swap out the front axle. Off the top of my head, a GM Dana 44 front would be a decent match with adapters on the rear. You could probably get a FSJ WT Dana 44 to work too. Or you could look into having the shafts/rotors redrilled to 5 or 6 lug 5.5" pattern.

 

[Ultrunner]

I've gotten a lot of great feedback; enough, I think, to make my decision. I am most likely going to stick with the AMC20 and do the upgrades. Single piece shaft, truss reinforcement, disc brakes.

In the long run it'll cost about the same, but the work will be pretty straight forward and less of a hassle. Not to mention the front axle won't need to be modified.

Thanks all.

 

[coldair]

What do you plan on doing with your jeep. You might not even have to truss it if your not wheeling hard.

 

[Ultrunner]

What do you plan on doing with your jeep. You might not even have to truss it if your not wheeling hard.

Good point, and no, I am not planning on any hard wheeling. So maybe just the single piece axle upgrade will be enough reinforcement.