I plan to swap the rear end on my YJ with a ford 8.8. To do the swap I will obviously need to relocate the spring perches and shock mounts. It makes no sense to me to go through the trouble of welding new perches on and putting the springs back under the axle as it came from the factory. So, for added ground clearance I would like to put the springs on top of the axle (SOA).
Here's my question.... I have already done a 4" rough country lift with new leaf springs. If I do the SOA with my 4+ springs I'm going to have about 3 more inches of lift in the back and overall more then I need for my 33s most likely. Should I get new springs for the back? (to lower it) Should I get components for the front to raise it a few more inches? (what will I need) Should I do the SOA on the front? Should I shut my cake hole and put the springs and perches back undle the new 8.8 rear end?
You guys are the experts. So, I would greatly appreciate some advice.
More info if you need it:
I ride wooded trails, play in the mud and on smaller rocks. I am not looking to build a rock crawler. The new axles will have 4:10 gears. I run 33x12.5x15 Pro Comp Xtreme Muds (so far I love them) and I have a 4.0ltr. I plan a SYE an CV axle no matter what dirrection I go with the springs.
Your right about the spring on top of the axle with the 8.8 conversion You'll have to fabricate new spring seating points right on top of the 8.8 axle tube. I've even added a couple of tabs around the springs to make sure they wont POP out with long articulation.
You'll have an adventure trying to get the E-Brake functioning properly after the 8.8 conversion. There isn't an E-brake solution without some fabrication. After that, you've got a "custom" braking solution that you'd better understand.
Aactually, the SOA on an 8.8 will net you a little more than 4" of lift, and that would be on top of the 4" springs you have...thats a very tall lift, and a lot more than really needed for 33" tires.....(I've actually ran 37" tires under that kind of lift in the past).
So you definitely need to consider either flatter springs (No lift springs, Wagoneer springs, or Rubicon Express 1.5" SOA springs, for example).
Considering you metioned you do not rockcrawl, IMHO, I would stick with a spring under setup if under your circumstances, with your 4" springs, its ok for 33" tires....gives you a more stable, lower center of gravity, and you have to mess with less custom fabbing for shock mounts, brake lines, e-brake, etc....
2009 JK X 2 door
Stock for now.
i wnet from SUA with worn out springs with 2 inches clearence on the rear.....with plus one on shackles...to SOA with new springs and have 12 inches clearence.....still have plus one shackles.. I dont do rocks, i do hunting leases with some decent mudholes. planning on removing +1 shackles, and will have MAjor clearence with probly 35s . i do plan on full size axles with a cummins 3.9 diesel later too. to help offset flipping issues.
I'd get the 1.5" soa springs. They're made for it. Spring eyes are flipped. I'd go purchase the right perches. You go with the 4" springs sprung over and you'll be asking for multiple problems. I've done tried it. Perches aren't that expensive. You can get the springs for about $160 a piece.