Soa vs sua

mehbohdi

New member
Searched forum this morning could not find any real info for or against Spring over vs Spring under lifts. I'm new to forum but not new to 4wd's. Looking for best articulation w/ 33-35" tires and best road manners (not freeway). Is it just a matter of preference or is there a difference, in overall performance? Thanks for input.
 

From what I understand a SOA (spring over axle) has some extra costs associated with it, and normally nets between 4-6 inches of lift. I believe that with a SOA you'll end up having to address the driveshaft lenght, and may have to go with a high steering setup.
 
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In the long run it is cheaper to stay with a spring under. It is a lot less headache. There are a few things to consider. Rear axle wrap, you need to make some type of torque arm that will address this issue. The other is steering. As TerryMason stated you my need to go high steer and deal with driveshaft issues as well. In my opinion I personally would stay with spring under and use the wider Jeep YJ springs this will net you with a better set-up and a lot less headache.
 
Since you said you're looking for the best articulation, SOA wins that hands down. It's well known that arched springs don't flex, but a SOA with relatively flat springs will flex like mad. I run 1.5" Rubicon Express SOA springs and had stock springs with an add-a-leaf before that. Both flex great. Mine is set up with about 2" compression and the rest is droop.

I have no traction bar setup and I get no problematic axlewrap behind by 4banger. A larger motor may be a different story.

Mine is very stable on the road, and I run no swaybars or track bars.
 

As bounty hunter has stated, a SOA wins hands down for flexing, period! I had a 79 cj5 with SOA and I loved the look, but I have to admit that all the down sides that have been posted above are and will be issues. I had a v8, so maybe axle wrap with a smaller engine wont be such an issue as bounty has stated.
 
Bounty is correct. Just keep in mind that SOA tends to be more work than SUA lifts... And you will need to make some things yourself in omst cases. Not saying it is not worth it, just making you aware...
 
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