Help With 1973 J4000 Springs

[40-Torpedo]

Hello All -
First time posting. Recently bought a very worn but unique 1973 J4000 Truck. This is my first Jeep in over 20 years. One of the many items that need attention with the truck are the leaf springs. The front leaf springs are nearly flat (no arch at all) and the rear are not much better. (She has seen a hard life) My question for today is who makes replacement springs? It seems that in the list of parts suppliers the 73' J4000 is about a unicorn when it comes to anything. For example: In looking over General Springs site it only lists springs for 1977 to 1992 J series trucks. None of the earlier models.
Thanks in advance!

[Phils67]

I just installed 52" GM springs in the rear of my short bed fairly easily and inexpensively. Being you have a J4000 you'll want a longer spring if you did that. Good luck finding bushings for post mount style. I recommend converting and never looking back. Write up is under build threads if you want to check it out. Four Ford Ranger shackle brackets worked out well for mounting. You'll have to swap shackles to GM also. If you want to remain stock you could always take measurements and buy bronze bearing stock and make your own bushings. Personally I'd say convert. Gm stuff will be available until doomsday

[Stuka]

Hell Creek Suspension makes kits for this truck. One of the tricky things is there were a few variations in the post mount size. So if you order from Hell Creek, they will need a few measurements so they know what size bushings to include.

You can go with custom springs from several makers, but you then have to track down the oddball bushing sizes yourself.

A third (and more complex) option is to update it to 76+ springs. This is arguably the best solution for ride and spring availability. But, its significantly more work which one of our members here just did. But, at the same time he updated the axles, and went with GM springs. But the work is similar: viewtopic.php?f=12&t=18528

[Phils67]

You can also use later model j-truck rear springs with those ranger brackets. They keep the springs off the frame to where they are about perfect in line with the rear axles perches. Might need a 9/16 washer or two on J-truck springs to take up the bushing gap in the brackets,not a huge deal though

[40-Torpedo]

Stuka and Phils67 - thank you for the info. If I get this right you are suggesting to use Ford ranger post mounts on the front and back and then use GM shackles on on both front and back and convert to a GM rear spring and a 76' & up front spring? Im not afraid of fab work.

[Phils67]

Front end you use later model J-truck and move the springs under the frame rail. I used the FSSR kit from rocklaurence at the front forward, CJ7 spring brackets on the front rearward with stock J-truck shsckles.

Rear end Ford ranger shackle brackets at both ends of the spring, opening facing downward on both, use GM springs and GM shackles in the rear. The ranger brackets are an off the shelf part by dorman you can get at any auto parts store.

[40-Torpedo]

Front end you use later model J-truck and move the springs under the frame rail. I used the FSSR kit from rocklaurence at the front forward, CJ7 spring brackets on the front rearward with stock J-truck shsckles.

Rear end Ford ranger shackle brackets at both ends of the spring, opening facing downward on both, use GM springs and GM shackles in the rear. The ranger brackets are an off the shelf part by dorman you can get at any auto parts store.

Perfect - thank you!!!

[Phils67]

This is still in its trial and error stage but so far looks to be promising. Truck is back on all 4 wheels, took a trip around the block today for the first time. Has a banging clunk in the rear so dont go jumping on this just yet lol I have to figure out where it's coming from this weekend, hopefully not the suspension. Part number for the ranger brackets is 722-010 if you end up trying to get them.

[Phils67]

Found my clunk... helps if you take the old leaf springs out of the bed before driving it hahaha