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Postal Jeep 79 what axles will work under this ?

SJR

Well-Known Member
Joined
Dec 23, 2006
Messages
392
Location
Bellingham WA
I may get a 79 Postal Jeep its RH drive and 2wd with a automatic, wondering what axles may fit under there to convert it to 4 wheel drive, anyone have experiance with these thanks Scott

looks like this here
Postal%20Jeep%20A1.jpg
 
You could throw a NT D30 from a CJ under the front, keep your D44 rear and have a cheap start to a wheeler. If that's not enough axle for you then scout or waggy width would be the next choice. Depending on what you wanted to spend the options could go on and on...
 
Depending on what side drop tcase but wagoneer dana 44s should be a good start with some yj springs :awesomework:


now speekin of springs
is there some springs that are longer that I could rework the shackle points on the frame and get a little longer wheelbase and a spring with more flex? Im new to the Jeep thing dont really know whats what, I already have a Dana 18 or 20 devorced transfercase and may go with a Subaru engine out of a Legacy 2.2 MPFI boxer , thinkin about runnin 33 x 1250 swampers as I already have a set ,Im in Washington state and like the inclosed box on the postal, also would be good to keep the kids in the back, also it was free from the neighbor Scott
 
cool got any pics, did you keep the postal body?

I've got a flatfender on it. The outboard shackle mounts on the rear worked with a little customizing. The fronts are in different spots, but still under the frame. Most of the front hanger is out front of the bumper atatched to heavy square tubing.

The perches for the front were good. The rear perches needed to be moved a little.

It all lined up good with my dana 20.
 
Rick Pewe or Jimmy Nylund did an article on 'How to' convert one of these a few years back on 4Wheeler magazine. You might check the archives, or send them an email. I'm sure they can tell you what year, issue. Then you can buy the old issues.

If I recall correctly, these postal bodies are HEAVY. They were made much more durable than the civilian jeeps, as a delivery vehicle is pretty tough on a rig.

http://www.fourwheeler.com/featuredvehicles/129_0605_1975_jeep_dj_5d/index.html
 
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heres a pic I found I like

JEEPDOOR2.jpg

That's badass....

I helped a buddy build a postal....It's got 31's ... We used a 25/27 front cause we had it...A NT 30 will bolt in....You'll have to mod the engine crossmember and add a crossmember under the radiator. The stock member won't clear a pumpkin. He pulled a 2.2 liter diesel out of a 4wd Isuzu Pup and we used the engine tranny/t-case from that...The gearing sucks but it does ok for what it is....the postal body is definitely heavy...and top heavy at that. We cut the doors so the windows could still slide down..but they still don't have good enough clearance to open them and leave on for wheeling.
 
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help me out when loookin for axles which ones are narrow which are wide, would like to keep it the narrow CJ width

Except for the 82- 86 CJ, all the CJs (60s thru 1981) are narrow.
The next wider axles are YJs, TJs, GrandCherokees (ZJs), Cherokees (XJs), Toyota pickups, Scouts, old Broncos, old Land Cruisers (FJs) etc. Each of these conversions has their pros/cons.

Before you buy any axles, you should ask yourself: What do I want to use this for, once I'm done? If it's a street jeep, then buy some YJ axles. YJ axles aren't very strong (but plenty strong for street use) and are often discarded during upgrades. Therefore they are often sold on Craigslist cheap. Since they can often be bought as a set, are relatively new, are narrow enough to fit under a jeep, and are also already set up for leaf springs, it can be argued this is a good choice. The downside, is they are 5 on 4.5 wheel lug, don't have a conventional wheel hub/wheel bearing, and a little weak. Then just get a set of FACTORY take-off wheels (also pretty easy to obtain) and mount your tires. Voila. Yer done. These are typically a Dana 30 / 35 combo.

CJ axles are slightly weaker fronts, slightly stronger rears. CJs used a Dana 30 front / AMC 20 rear (and sometimes a Dana 44 rear) The CJ vintage Dana 30 fronts had less casting in the housing, and was more prone to flex, ergo, breaking things. The AMC 20 rear was a strong housing, with axle tubes that were prone to spinning inside the housing, and a two-piece rear axle shaft. Those shafts were prone to failure. The good news is they shafts were 5 on 5.5 and had conventional wheel hubs and bearings.

Toyota (old pickup) axles are also a nice swap.

As with all of these configurations, plenty of aftermarket parts/pieces are available for you to polish these turds (smaller-type axles).

But before you start: WHY are you building this? If you're building it for a wheeler, you might consider stopping, and starting with something else. These bodies are HEAVY, top heavy, bulky (too bulky to fit many of our trail systems) and require major modifications to convert to 4x4. Since you're asking relatively easy questions (like, ummmm, what axles to use?), it can be assumed that you're relatively new to doing major re-configures. If I were you (and I ain't), I'd start with a YJ.

However I'm not you, so when I build my rigs, I bought a YJ, and a TJ wrangler. The YJ, I converted the axles to Scout Dana 44s front and rear. They are much stronger than the Dana 30/35 combo, come in 5 on 5.5, have bigger bearings, wheel hubs, and had plenty of aftermarket parts available (I chose chromoly shafts, CTM u-joints, Detroit Lockers). These shafts served me reliably until I upgraded to Dana 60s.

Good luck with you build, whatever you choose.
Tony
 
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Also, one thing to remember, whatever shafts you choose, will also dictate what transfer case to use. The front axle can be either a Passanger drop differential, or a Driver's drop differential. Both are OK, but the transfer case must have the correct output to match the front diff.

Since you also have to do a transfer case conversion (or an entire engine/tranny/t-case) you MUST make sure you've got the correct Tcase before you buy your axles
 
Except for the 86 CJ, all the CJs (60s thru 1985) are narrow.
The next wider axles are YJs, TJs, GrandCherokees (ZJs), Cherokees (XJs), Toyota pickups, Scouts, old Broncos, old Land Cruisers (FJs) etc. Each of these conversions has their pros/cons.

Before you buy any axles, you should ask yourself: What do I want to use this for, once I'm done? If it's a street jeep, then buy some YJ axles. YJ axles aren't very strong (but plenty strong for street use) and are often discarded during upgrades. Therefore they are often sold on Craigslist cheap. Since they can often be bought as a set, are relatively new, are narrow enough to fit under a jeep, and are also already set up for leaf springs, it can be argued this is a good choice. The downside, is they are 5 on 4.5 wheel lug, don't have a conventional wheel hub/wheel bearing, and a little weak. Then just get a set of FACTORY take-off wheels (also pretty easy to obtain) and mount your tires. Voila. Yer done. These are typically a Dana 30 / 35 combo.

CJ axles are slightly weaker fronts, slightly stronger rears. CJs used a Dana 30 front / AMC 20 rear (and sometimes a Dana 44 rear) The CJ vintage Dana 30 fronts had less casting in the housing, and was more prone to flex, ergo, breaking things. The AMC 20 rear was a strong housing, with axle tubes that were prone to spinning inside the housing, and a two-piece rear axle shaft. Those shafts were prone to failure. The good news is they shafts were 5 on 5.5 and had conventional wheel hubs and bearings.

Toyota (old pickup) axles are also a nice swap.

As with all of these configurations, plenty of aftermarket parts/pieces are available for you to polish these turds (smaller-type axles).

But before you start: WHY are you building this? If you're building it for a wheeler, you might consider stopping, and starting with something else. These bodies are HEAVY, top heavy, bulky (too bulky to fit many of our trail systems) and require major modifications to convert to 4x4. Since you're asking relatively easy questions (like, ummmm, what axles to use?), it can be assumed that you're relatively new to doing major re-configures. If I were you (and I ain't), I'd start with a YJ.

However I'm not you, so when I build my rigs, I bought a YJ, and a TJ wrangler. The YJ, I converted the axles to Scout Dana 44s front and rear. They are much stronger than the Dana 30/35 combo, come in 5 on 5.5, have bigger bearings, wheel hubs, and had plenty of aftermarket parts available (I chose chromoly shafts, CTM u-joints, Detroit Lockers). These shafts served me reliably until I upgraded to Dana 60s.

Good luck with you build, whatever you choose.
Tony

Also, one thing to remember, whatever shafts you choose, will also dictate what transfer case to use. The front axle can be either a Passanger drop differential, or a Driver's drop differential. Both are OK, but the transfer case must have the correct output to match the front diff.

Since you also have to do a transfer case conversion (or an entire engine/tranny/t-case) you MUST make sure you've got the correct Tcase before you buy your axles

Awesome lots o good info I havent really decided what direction Im going with this, but with the help of you guys I will at least be able to make a educated decision and prevent hardache down the trail thanks Scott
 
For what you'll be able to do with this rig, pick up a CJ dana 30 and bolt it in..72-about 82/83..My guess is that it will have 3.73's in the rear which is a common ratio. It also has a 44 with one piece axleshafts..Worth keeping IMO. It will never be a hardcore wheeler unless you swap bodies down the road...Which is a good possibility seeing as a CJ tub from 53-75 will practically bolt onto the frame and give you a better foundation than an actual CJ frame. You can keep the same fenders/hood grill combo from the postal. You used to be able to get a lift spring for the rear from Gitz (Sp?) Spring in Auburn, but I don't know if they are still making those.. In the front we used a set of prototype flattie rear springs that someone had passed onto me that didn't quite fit anything but they worked well on the postal...Alot of guys have done a spring over with CJ7 rear springs in the front but that will involve a little addition to the front of the frasme to make work because of length. Most do a shackle reversal at the same time. The possibilities are endless depending on how far you want to take it as a postal and you have tons of JEEP options if you want to ditch the postal body down the road...
 
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