I was wondering if that would cut it to stuff 31 under my sammie? I could only find 2 inch sakles noting bigger

i ordered some 3 inch shackles from trail tough products today front and rear for 109 shipped

You will need to cut a bit of fender out to make it fit, but it's doable.  Maybe switch to a flat fender style front, in the rear cut out the wheel arches so they are flat.  Most people looking to run 31" tires go with a SPOA (Spring Over Axle) to make it fit.

We need a lift to tire size guide to add to the FAQ over in the Repair section.  

you could always make your own shackles just use flat bar and if you know how to weld your golden, just have supports welded in the middle and drill your holes.....all finished! that at most i'm guessing would run like 60 bucks combine that with the 2" body lift from Rocky-road and you got like 6" of lift for less then 200 bucks!

A 2" shackle will only give you 1 " of lift I think you will need at least a full 3" of lift for 31" tires.

2" of shakle = 1" of lift....you might be able to fit the 31's but they will rub like crazy and when you wheel it's hit hard. Once you get into 2" plus on shakle it's going to play with the front angles and it'll be hairy to drive.

Save the money and get the SOA, extended brake lines and steering correction...or you can do like me. I took the SOA off and installed some revolvers, 512's, locked and 30" BFG muds. You just have to make sure to stay out of the ruts and it's amazing where it'll go. I'm not into crazy mud but I get by every where else.

We've got a local trail called crack that the local Jeep club labeled as being a 33-35" minimum tire size with lockers and winch. I got throught before lockers and with no winch....unassisted from anyone else but my spotter. We stacked rocks but we got her done. there were a few beauty marks on the zuke.