spring under axle swap...WTF?!!

I have a bass-ackwards kind of question for everybody here.
(i'm still a newb,and kind of technology impaired...but i did search)
i want to know if anyone has tried going spring under to fight axlewrap
i have had 2 stock cherokees and twice destroyed spring packs
now i want roughly 3.5 to 4 inches of lift and bigger tires but i dont want the same problems i have a real atraction to the skinny pedal and power shifts and wheel mostly mud. i guess what i want to know is does anyone have any idea what springs i would use or would i be better off building some bastard superstock spring set-up?

To help prevent it, do a search on 'traction bar'.

Here is a good thread on the subject... http://www.naxja.org/forum/showthread.php?t=87177

There are othe way to go about making a traction bar though.

It's a bad idea...


Spring wrap is caused by many things - almost all of them can be corrected. If you were to compare a truck that rode at the same height and had the spring hangers in the same location but one was SOA and the other SUA - the SUA would have less wrap BUT only because the leaves would have much greater static arch and thus be effectively much stiffer. FWIW, my SUA MJ wrapped like a mother until I added an extra main leaf to the packs and went SOA. No problems since.



If you want 4" of lift keep it SOA and use some dakota or S-10 leaves to give the pack a little more arch and a bit high spring rate. No lift blocks.


If it still wraps, build a centre anti-wrap bar. They're pretty simple.

If you went spring under and want 4" of lift, you would have to have some major arch in the springs, something similar to a 9"+ lift spring. You would have to weld new spring perches on and maybe relocate the shock mounts.
Why not just get an antiwrap bar or traction bar. If you dont want to design one there a few companies that make them. In the long run, it would be cheaper to get the bar and you would maintain the better ride and better flex of the SOA.

EDIT: Man I took way too long to type my answer.

ya i didn't thik of just how deep the arc would be
but flat springs wrap horribly. i just read timmays traction bar article (thank you for the link) and he had s10 springs for 4 inches of lift and still had wrap enough to require the bar so springs alone wont cure it

Get a set of Big Offroad springs. They have the extra half leaf that really helps. The first time on the street with my stroker broke my Rusty's springs. I have wheeled and abused my BOR's with no effect.

Wow. While I suppose the spring-under setup does, to some degree, present less axle wrap (due to a shorter lever arm for torque), I can't believe it will save you from damage if you're that possessed with the skinny pedal. I can't believe you're destroying springs before snapping axle shafts!

For mud, I would think under-vehicle clearance would be a serious concern...hence spring over. Won't going spring-under destroy some of your clearance issues? Also, to get the same lift with spring under, you're gonna have to do something to get get more spring flex (longer shackles, etc.), otherwise the springs will bind (won't have room to flatten from all the arch necessary to gain the lift from the spring under).

Just my 2 cents...

I destroyed the springs in my old rig an 87 4litre with the peugot 5 speed
with alot of powershifts the axle wrapped far enough to bind up the rear shaft