Full Size Jeep Network

Yes this has been covered many times, but I have not found what I am looking for.

Have a 72 J4700 with plans on running 5.7 eagle head hemi, NV4500, and NP205. The wife and I want to keep this thing as stock looking as possible with the exception to the modern drive train.

I want to swap out the front axle to a dodge 44 and move the front springs under the frame. I have found 5, 6, and 7 leaf packs that are OEM to 76+. If I move these under the frame, how much lift can I expect? The front sits pretty low due to the worn out post mount stock springs, guessing 3". I am just worried that it will lift it way high but maybe I am over thinking things. Plans for the rear springs are to have them rebuild and keep them.

Any advise on what rate springs to use would be much appreciated. Plans for the the truck are a daily driver with towing capabilities.

5 Leaf Pack - https://www.sdtrucksprings.com/index.ph ... 3b390535c8

6 Leaf Pack - https://www.sdtrucksprings.com/index.ph ... 3b390535c8

7 Leaf Pack - https://www.sdtrucksprings.com/index.ph ... 3b390535c8

If you mount the springs on top of the axle, it will give you 6-7" of lift depending on pack thickness and spring perch height.

This is because all FSJ's made 74+ had the front springs mounted under the axle. Wagoneers were spring under front for every year. Only '73 and older J-Trucks had post mount front springs.

The links you posted are giving me a 403 error, however, you can buy stock height 74+ front springs from several places that are specific to FSJs. For your rear springs, you can also buy new springs that fit your post mount from Hell Creek. I would advise against trying to rebuild your stock 50 year old springs.

At least some of those springs are available on Amazon with Prime delivery. Search for the part number. There they are sold under the Dorman brand. https://www.amazon.com/Dorman-97-372-Sp ... B09HYZJN77

Thanks Stuka, this is what I was looking for.

The 6 - 7" lift will be too much, I guess it's back to the drawing board. Probably just grind out the lower portion of the cast iron and burn in a perch to make it SUA.

From what I have gathered, the open knuckle 44 has a wider turning radius than the closed knuckle and the post mount springs would be in the way.

tgreese wrote: ↑Thu Mar 09, 2023 7:13 am At least some of those springs are available on Amazon with Prime delivery. Search for the part number. There they are sold under the Dorman brand. https://www.amazon.com/Dorman-97-372-Sp ... B09HYZJN77

Any advice on what springs to start with? 5, 6, or 7 leaf.

Geez, dunno. You could guess at how much the springs will collapse, and measure where you want to mount them. The parts book probably shows the springs used for each of the GVWRs. There is both a parts book and a TSM for '82 on the Tom Collins site. '82 should be representative of these years. All these trucks have roughly (ha, that's an unintentional pun) the same ride height, with the only change being the bump stiffness with increasing GVWR. The unladen weight is about the same for all.

Phil did this conversion on his Pre-'74 Gladiator. He did a great job. Look here viewtopic.php?p=208452&hilit=FSSR#p208452

lpukas2 wrote: ↑Thu Mar 09, 2023 8:50 am Thanks Stuka, this is what I was looking for.

The 6 - 7" lift will be too much, I guess it's back to the drawing board. Probably just grind out the lower portion of the cast iron and burn in a perch to make it SUA.

From what I have gathered, the open knuckle 44 has a wider turning radius than the closed knuckle and the post mount springs would be in the way.

You could look around for a 74-79 J-Truck or WT Cherokee front axle. They are already cast for spring under, and are the correct width. If you are wanting 5 lug or 8 lug, you can swap the outers.

And yes, your tires would rub the post mount springs if you wanted the extra turning radius. Though you could always adjust the steering stops to prevent it.

rocklaurence wrote: ↑Fri Mar 10, 2023 10:34 am Phil did this conversion on his Pre-'74 Gladiator. He did a great job. Look here viewtopic.php?p=208452&hilit=FSSR#p208452

Been like 3 years or so now and still riding, hauling, towing and handling great. Ride quality is far superior. No regrets whatsoever! With 235/85R16 the fender openings are about 36" when going SUA with the FSSR. I'd say about 3-4" over stock tops but don't have a stock ones measurements for reference

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You could look around for a 74-79 J-Truck or WT Cherokee front axle. They are already cast for spring under, and are the correct width. If you are wanting 5 lug or 8 lug, you can swap the outers.

And yes, your tires would rub the post mount springs if you wanted the extra turning radius. Though you could always adjust the steering stops to prevent it.
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Keeping an eye out for a Jeep axle but the 63"+ ones are hard to find. Planning on just grabbing a Chevy 44, SUA the axle and swap the outers out for the Dodge ones, the Dodge axle will not work SUA. Or if I find a well-priced 44/14 bolt combo, grab that.