anyone running the yj spring conversion under axle? i'm thinking of staying under so i don't(hopefully) have the steering problems associated with over the axle. i should still get 3"-4" of lift and better ride and be able run a 31/10.5 tire. is there anything that would convince me to go over now as compared to later. i say later because my kids (14,10) will be driving this sammy on the trails too unless i find something else for them.
are there any problems, quirks to this setup i should know about? HELP.

You will at least need a drop pitman arm or bump steer will occur. With the YJ flex you may need longer brake lines. Longer shocks and bump stops moved down.

I have considered this myself but one thing leads to another.  3-4" of lift, bigger tires, bigger tires need gears, might as well lock it front and rear with the gear swap. Locked front, power steering.  If you go with transfer case gears then you better beef up the case mounts so you don't twist it out of the frame or bend the arms. Then be careful you don't bust the case. Now you can go rock crawling and need sliders, diff armor and skid plates.


What I've been told is realistically you get about 2.5" lift with stock YJs. Then you can get away with lowering the bump stops and longer shocks and a drop pitman arm.

I run SPUA with YJs in the back and rear springs up front (RUF).  I like it.  Low center of gravity (COG). Nice, evenly balanced flex.  Not bad for the approach and departure angles.....worth it for the lower COG, IMO. Can't really comment on the ride and bumpsteer, since it is trail only.
I am running cut fenders and clear 31s with no problems.
I am not running a dropped pitman arm.
I am running lowered bumpstops (1" in the rear, 2" in the front) to keep the springs from negative arching.
You need to keep the axle in the stock location, when running SPUA to keep the steering links from binding/hitting on each other.
I used the spring relocation plates that are spec'd for the YJs or RUF (depending on where you find them).
Rear springs are a little longer than stock front springs, but not as long as YJs.
I am running longer front shackles (2", IIRC).......1) to correct the shackle angle.  2) to adjust the caster slightly (that was a nice side benefit....it was mainly for #1).  Longer front shackles gave me about 1-1.5" of lift.
To make the rear spring pack for front use, I removed the overload leaf from the rear pack, took 2 leafs out of the front pack and put in the rear pack....it made a 5 leaf pack, which is needed for my heavy front bumper and winch.  I gained about 1-1.5" of lift by doing this.
I am also using longer front shocks (with new upper shock mounts) and longer front brakelines.

I've seen Skyhi's rig in action and it works VERY well.

my plan is to install the springs and missing links then flex it out to see what is in a bind. whatever is binding or close to binding i will replace with longer items. just don't really want to go larger than 4" lift and 31/10.5 tire with the kids driving it, too. not yet anyway.

Thanks Smuz.......I would have to agree

I don't run MLs either.....not that I really have anything against them.....I just don't have them.