theislandnut Posted December 12, 2015 Share Posted December 12, 2015 I need completly new rear springs for my MJ. I was wondering if you have found some thing that swaps over and is a little softer while maintaining some payload abilities. I am thinking mid 90's Ranger or Bronco II. There 3/8" shorter on the pin location and overall length, the same width and can be found depending on year with 3, 4 or 5 leafs, the MJ has 4. The MJ leafs have a 1280lb spring rate. The ranger leafs have a 1250lb spring rate and early ones are 1100lb, the ranger spring would also give a small lift when mounted SUA. The bronco leafs 1020lb spring rate and would also give a small lift when mounted SOA. What do you guys think and what other swaps have you found that work both on and off road. Link to comment Share on other sites More sharing options...
Pete M Posted December 12, 2015 Share Posted December 12, 2015 MJ springs are pretty darn soft already. what shocks do you have? Link to comment Share on other sites More sharing options...
theislandnut Posted December 12, 2015 Author Share Posted December 12, 2015 Just the OEM shocks. I will likely be going SOA, so new axle side shock mounts will have to be fabbed at the least, then I`ll flex it out and see how much longer a travel shock I can run. Since I have to make the lower shock mount I`ll also incorporate the airbags mount into it. I`ve got a Firestone I believe the 2350, air bag load leveling system for the rear that when needed will carry the load and still flex on the trail. It`s the long travel cylindrical bags not the chubby ones with very little travel. Since I`ve got OBA I can adjust on the fly. Link to comment Share on other sites More sharing options...
Jackrabbit41 Posted December 13, 2015 Share Posted December 13, 2015 I need completly new rear springs for my MJ. I was wondering if you have found some thing that swaps over and is a little softer while maintaining some payload abilities. I am thinking mid 90's Ranger or Bronco II. There 3/8" shorter on the pin location and overall length, the same width and can be found depending on year with 3, 4 or 5 leafs, the MJ has 4. The MJ leafs have a 1280lb spring rate. The ranger leafs have a 1250lb spring rate and early ones are 1100lb, the ranger spring would also give a small lift when mounted SUA. The bronco leafs 1020lb spring rate and would also give a small lift when mounted SOA. What do you guys think and what other swaps have you found that work both on and off road. I just bought new stock beef springs from general spring. 4 day shipping! Link to comment Share on other sites More sharing options...
daking Posted December 13, 2015 Share Posted December 13, 2015 I also ordered General springs. I went with the 3+1 setup 10" arch. So its soft, and flexible. I'd say almost as flex as the old springs. Image Not Found I need to adjust the shocks. The shock is limiting the down travel. Image Not Found Image Not Found Link to comment Share on other sites More sharing options...
theislandnut Posted December 14, 2015 Author Share Posted December 14, 2015 That is one nice MJ. With such a large arch to your spring do you find the tire contacts the wheel well when flexed. Do you have any idea what the stock arch height is on an MJ leaf pack. I got a lot of the spring comparison info from General Springs site and only saw two stock MJ springs listed. Do they also sell a all in one lift spring, or did you add a leaf to the stock pack. The problem I am finding is I need entirely new sping packs and only want 2" of lift and I don't want to do it with spacers, add a leafs or shackles. I would also like to SOA the rear while I am at it so that pretty well eliminates the stock spring pack sticking with only 2" lift. I think that by using a ford 1020lb bronco II springs mounted SOA. I can easily find a stock set for cheap to experiment with. Link to comment Share on other sites More sharing options...
Pete M Posted December 14, 2015 Share Posted December 14, 2015 soa lifts 5-6". your leafs would pretty much be a negative arch to bring that back to 2". why do you need to go spring over? 2wd packs (with a second main leaf) and I had a bit over 5" of lift. Link to comment Share on other sites More sharing options...
theislandnut Posted December 14, 2015 Author Share Posted December 14, 2015 Yes SOA with the stock pack is 5 or 6 inches of lift. I only want 2" at the max. As for why SOA, it flexes more and has less to get hung up on. By running a relitively flat spring pack mounted SOA in a MJ I will end up where I want to be. Less arch also means less tire movement in the wheel opening and it is forwards movement when run in the rear. Link to comment Share on other sites More sharing options...
Crash Posted December 14, 2015 Share Posted December 14, 2015 831_xj over at naxja just made up a set of U-bolt eliminator plates for his F8.8 that he swapped into his now SOA MJ. This, helps counter the added height. Looks like they sit just on top of the tube. Has gussets from then edges of the plate to the axle tube. Link to comment Share on other sites More sharing options...
daking Posted December 14, 2015 Share Posted December 14, 2015 That is one nice MJ. With such a large arch to your spring do you find the tire contacts the wheel well when flexed. Do you have any idea what the stock arch height is on an MJ leaf pack. I got a lot of the spring comparison info from General Springs site and only saw two stock MJ springs listed. Do they also sell a all in one lift spring, or did you add a leaf to the stock pack. The problem I am finding is I need entirely new sping packs and only want 2" of lift and I don't want to do it with spacers, add a leafs or shackles. I would also like to SOA the rear while I am at it so that pretty well eliminates the stock spring pack sticking with only 2" lift. I think that by using a ford 1020lb bronco II springs mounted SOA. I can easily find a stock set for cheap to experiment with. Thanks. When I called General Springs, They told me there are 3 "Factory" type springs plus the metric ton. The 3 factory types are the 3 +1 design. The differences was the free arch. 10" was the most, the other 2 designs had less arch. I'm thinking the original springs I had wore most likely the middle range ones. The truck started out as a 4X2. The new General Springs raised the rear just over ~2", returning the factory "rake" . I did the SOA conversion and the jeep sat level for awhile. Then I added the tire in the bed, moved the battery to the rear, and added a heavy rear bumper. After that, the rear was about 2" lower. I was deciding on a solution, I really did not want to put in new springs. I was concerned about flex, or lack of it. I was tempted to put ~2" lift blocks instead. I called General Springs and they have lots of info. I was going to order 3+1 springs with military wrap, but they wore going to take a month. Ended up ordering the last set of Comanche springs they had. Over all they are good. I'm happy I've made basted packs for other trucks in the past, and that has worked too. I think your idea sounds good. You should call General Springs, They have lots of info on Comanche springs. They can make what you need too. Link to comment Share on other sites More sharing options...
theislandnut Posted December 14, 2015 Author Share Posted December 14, 2015 That is why I want do do the SOA conversion with a readily available stock pack not a bastard pack or one that is the last one available , that can can also be found in many different lifts if I deside I want more later. Link to comment Share on other sites More sharing options...
theislandnut Posted December 14, 2015 Author Share Posted December 14, 2015 831_xj over at naxja just made up a set of U-bolt eliminator plates for his F8.8 that he swapped into his now SOA MJ. This, helps counter the added height. Looks like they sit just on top of the tube. Has gussets from then edges of the plate to the axle tube. You only have the the round part of the u/bolts below the axle on a SOA. On a SUA you can clean it up with u/bolt eliminator plate but you still have the plate below the pack and the bolts. Ford ran flat u/bolts on some of the dana 60s they put up front and offset plates so you also don'th have the thickness of the bolt. If I end up staying SUA for some reason I have a set of the offset Fords, they add only 1/2" to the pack and with the offset to them they slide on and off $#!& easily. The also have the lower shock mount built in, you would see a clearance gain of over an inch and have a much cleaned up underside. Link to comment Share on other sites More sharing options...
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