axles, SPOA, 79 CJ-7

[mrVfr]

I recently bought a 79 cj-7 it already has a AMC 360 v-8 and TH 400 tranny. It also has the full time four wheel drive quadra-loc transfercase (which I hear is a pretty sturdy unit) So without saying the obvious weak link is the stock axles. right now it is on 33x12.5 mud terrains with an unknown small lift (under-axle). I would like to swap axles, do a spoa, and do bigger rims/tires all at once. In the end I would like to fit somwhere between 35-38 inchers. I have heard that the 70's vintage bronco offers axles a mere inch wider than stock Ford 9in rear wth 44 front, however I think the 44 might not be quite beefy enough. Also how good is the 8.8 ford the interest there lies within the idea of rear disc brakes. Any insight will be much apprecieated. I want to do it right and do it once.

[Sully]

One thing you dont want is the quadra-drive 4wd system. Get rid of it. Axles would be a great idea considering you have the narrow track axles(76-81). A ford 9 inch and dana 44 will be plenty strong for 35's. You could run 37's on those axles if you wanted to. If you do an SOA and only want to fit 35's try to find some stock 91-95 Yj leaf springs. The front springs are wider than the wimpy Cj ones and they are newer and should be in better shape. Doing it right the first time is the best thing you could do. Cheaper in the long run. Have fun with you project and let us know how it goes.

[Junkpile]

If you swap axles, you will either need to use a rear axle with an offset diff to match the Quadratrac Tcase, or swap Tcases too. The QT system is okay in the right Jeep and can stand up to 35s with proper service.....but I wouldn't do an axle swap around one.
The early Bronco stuff is quite a bit wider than your current axles. The front diff is also a drivers drop, which requires a drivers drop Tcase. You might as well go fullsize GM or settle on D44s and rob a Scout II or mix and match some SJ axles for an AMC20/D44 widetrack combo. Either could stand up to your planned tires with some simple beefing. All require the same mods be done in the front and the back is easy, so if you did go with the SJ or Scout D44 axles now, you could easily go SOA on some fullsize GM axles later if the need were to arise.

[mrVfr]

thanks for the info. Always learning new things. I hadnt thought about the off-set rear axle. I suppose I'll trade out the t-case too. I have a lot of time to figure it out. Gonna be fall before I have the oppurtunity to actually start tearing into this project. probably still gonna go with some lift springs even with the soa. I realy want to have alot of articulation and streetablity isnt a priority. Luckily the state of New Mexico is pretty easy-going in that sense.

[redrooster]

You have a lot of options depending on money, time and how big you want to go. It will be expensive to swap t-cases, but worth it. If you don't want to swap then you could find some Wagoneer D44's with the rear offset and the correct front. This will get you wider and strong enough to run 36's.
If you want to swap cases then you should try either a GM case like the NP205 (large case with 2.0 ratio) or the Dana 300 (small case with 2.62??? ratio). Then you will be able to get a more common centered rear and passenger side front axle (8.8 rear and a 44 front).
The 205 Case can be adapted by acquiring a used or new GM factory adapter and output shaft for your transmission. The Jeep and GM 400's are the same internally, so shafts and matching adapters can be swapped.
The best swap would be to the Dana 300. It is small, strong and will fit nicely. It also has a good ratio. The adapter kit is around $410 from Novak and includes seals, output shaft and aluminum adapter,
The transmission will have to be disassembled for the output shaft swap with either case. Driveshaft mods will have to be made also (you will need them with an SOA anyway).
I have a 78 CJ7 with the AMC 360 TH400, Novak adapter and an Atlas II case (same pattern and shaft as the Dana 300 uses). PM me if you have any questions.