Keeping low COG with SOA?

[jakesmog]

I was intrigued by a thread about an XJ that runs 2-3” of lift with long arms and 37s in the name of low COG and it interested me, but obviously our trucks are not already SOA like XJs. 

That being said, I was hoping to acquire some wisdom on the best approach for keeping good ground clearance and low COG on the MJ. I’ve seen threads where people go SOA and use Dakota leaves or other bastardized packs, but I’m asking if anyone has any experience with this or could explain the options to me. I’m not the most experienced wheeler so I don’t really know how much SUA will really get caught on things.

 

It’s come to the point to ask because I’m about ready to swap to 4wd, and I need to pick a rear axle. A D44 seems ideal but too expensive, a 8.8 would be nice except being thicker and making it harder to stay low with SOA, so maybe the 8.25 is what I should look for? What else should I be considering?
 

I prefer performance over convenience. I’m cutting a lot of work out for myself but I’m also just brainstorming the build right now.

[Pete M]

the liberty 8.8 is very common in yards and a bit wider than stock so as to better accommodate the MJ's wide butt.   

 

if you want to run 37s on a 3" lift, why not just get a 3" lift?  an SOA is never going to be 3" unless the leafs are a negative arch. 

[jakesmog]

I was actually planning on running 35 or 33s on as minimal lift as possible. I wanted to explore the options of doing SOA to help with ground clearance on minimal lift, I was even thinking something like 2”. I’ve just read that SUA is not fun on rocks.

[89 MJ]

@ghetdjc320 is building a fairly low COG truck. Might want to check out his build thread

[ghetdjc320]

I went with these perches from Barnes SUA for higher clearance. Realistically, the wheels are pretty close to the springs so as long as you pick good lines while wheeling, you shouldn’t have much of an issue with anything getting hung up even in stock configuration. Notch flares open up the wheel wells a lot if you are still wanting some type of flare. Otherwise, a nice trim can give good clearance. DPG off-road has a great video on trimming for clearance while still keeping things looking clean. Widebody kits are another option if you like the pre-runner look. Last couple pages of my build thread have some pictures of what notch flares and metric 33’s look like mocked up. And the liberty 8.25 is a good swap candidate. You’ll have to clean up several brackets but the 3” tubes, disk brakes and screw type preload adjusters are all nice benefits. 
 

 

https://barnes4wd.com/products/sua-swap-combo

 

[jakesmog]

Thanks, those perches look like they will accomplish what I want and I wouldn’t have to completely redesign the entire frame just to go SOA. Now I have to resist the urge of thinking I can make those myself

[Pete M]

shock mounts will be needed.  and if you are avoiding anything hanging low, that might limit the amount of droop you can achieve. 

[Drahcir495]

If I'm reading this correctly, it will raise the axle up .25"? I am asking because I "need" to raise the axle in the scrambler a bit in the rear to level it out. I don't like how it sits with the arse end up like that. I've been trying to figure out how to do this?

[ghetdjc320]

2 hours ago, Drahcir495 said:

If I'm reading this correctly, it will raise the axle up .25"? I am asking because I "need" to raise the axle in the scrambler a bit in the rear to level it out. I don't like how it sits with the arse end up like that. I've been trying to figure out how to do this?

What are you referring to? 

[Drahcir495]

The Barnes 4wd kit. If it actually lifts the axle up towards the fender I could use that to level out the CJ.

[ghetdjc320]

I’m guessing that’s just a generic statement. You’ll need to verify how far your perches are from the axle tube vs the Barnes setup. 

[schardein]

SUA will do just fine in the rocks, I've been doing it for decades in my CJ.  

You may be able to do a U-bolt flip using junkyard parts, which is what I did on the Dana 44s in my CJ.  I used parts from 88-97 Chevy trucks (non-Z71).  I used the bottom plate, with a second bottom plate cut down to just the center section and welded to the full plate to double the thickness, to better protect the nut for the leaf spring center pin.  Then used the top plate and u-bolts, trimming the u-bolts to the appropriate length.

As Pete mentioned, you will need a lower shock mount. You can adjust how far the shock mount hangs down to make a compromise between suspension travel and ground clearance.  A shock mount welded to the axle that provides a double shear on the shock mount bolt will hold up much better in extended use in the rocks than the welded on stud of the factory design.

 

 

[Big_Mark]

The reason you might want to go SOA is instant 4-5" lift. Or as has been pointed out, it gets the U bolts pointing up so the threads and bolts don't get hung on stuff (and bent, damaged) when wheeling.

Problems with SOA include driveline geometry/length, leaf pack warping "S" shaped without anti wrap bar in place, basically it ends up being a lot of work to get right.

For your use case it seems to me SUA is the way to go unless you are building a "Hammer down" machine and are trying to stuff Dana 60's under it with 42" tires.