I'm feeling alot like a song by U2 these days- I still haven't found what I'm looking for...when it comes to the goldilocks of rear lift springs for my 2003 Xl7. For starters, there's not much to choose from, and what there is is only good for 1.5" lift or less. I am running around 3" of lift in the front and want my rear at least to match that. I'm currently running some scrapyard springs suspected of being from an Aerostar. They give the right height but they are a little on the spongy side, and the outside diameter is a touch big so they are rubbing on the spring pocket on the frame and making some annoying sounds. I have been doing some googling and found that some people run FRONT springs out of any Jeep with the 4.0L inline 6 motor (Cherokee, Grand Cherokee, TJ) with good results. I pulled a set out of a Grand Cherokee WJ (1999-2006) and tried them but they lowered the truck compared to the current springs. The diameter was perfect though. I found a specification chart http://www.sleeoffroad.com/installation/ome_spring_specs.pdf and looked up the OME 2968's for the XL7 - they are listed as a medium duty spring, with no heavier option available. Well, I am looking for that heavier option. I looked up OME springs for the Jeep WJ front, and found the 2936, listed as a heavy load spring.

The ratings for the XL7 spring is 210 LB/in or a OE spring rate of 120Lb, with a free height of just over 14.5".
The ratings for the WJ spring is 220 LB/in or an OE spring rate of 170LB, with a free height of just over 16.5".

So...I know nobody's going to come out and say they can confirm this will work because I know nobody's tried it, but it doesn't seem unreasonable to think that these WJ springs might be the hot ticket for someone looking for an HD XL7 rear spring, does it?

As you suggested, I haven't tried it personally, but, I would hesitate to go with a spring that much stiffer AND with that much more free length.

A higher spring rate with the same length will give you lift, and so will a longer spring with the same rate, some of the lifts I have installed have actually been higher rates with less free length.

Yeah, I noticed that when I put my OME front springs in- they were actually shorter than the stock springs but they gave lift. I was hoping this would be the case with the WJ stock coils since they have to support alot more weight than the rear end of an XL7 but this was not the case.

The only reason I am looking at this option is because I am trying to achieve a balanced ride quality between front and rear. I suppose I could try the OME XL7 coils but I'd need to run a spacer to get it to ride high enough, and I am trying to avoid a spacer if possible. Another option would be to find the same WJ coil but in a lighter load rating perhaps...

EDIT: the WJ light duty coil is the OME 2935. It rates at 180LB/in or an OE spring rate of 140Lb, with the same free height as the HD WJ coil at a little over 16.5".

Comparing the three, I'm still tempted to go for the HD WJ springs because they're only a little bit stiffer than the OME XL7 springs and they give the extra height I'm after. The light duty WJ springs might give the height but I think the ride will be pretty spongy because the Lb/in rating is quite a bit less than the XL7 medium duty springs.

Any more thoughts?

I tried the OME 2936 springs but they are too big in diameter to fit nicely into the factory upper spring perch. It's too bad cause I think other than that they might be perfect. It's tempting to modify or replace the upper spring perch but I don't know if it's worth it for me. Hopefully this info ends up being useful to someone else.

I am running lifted jeep springs in the back of my 93 2 door.  They were supposed to be 165# springs.  I cut the pig tail off, and bent the top and bottom of the springs in so they fit in my spring cups.  They leveled my tracker out and carry more load than stock springs with spacer lift.