off road the 4.56 works well and I have no complaints, even on the steep climbs. I do wish the jeep had a little more power on the freeway when going up the hills at 60-70 though. Sometimes I turn the OD off when running up the hills and that does put the jeep in the sweet spot.

my motor may not be that fresh compared to yours so you might have better results. when i checked my compression the readings were on the low side. also one time when i drove a stock XJ it seemed to have more pick up than my jeep. one other thing i wanted to mention, like others posted if you go to lower gearing than 4.56 the pinion gets very small and your taking a bigger risk on that part failing vs some other part. on that note, while building your jeep consider where you want your week parts to be so that you can easily (hopefully) change them out while on the trail should things go south.

when i was looking into building up or replacing my axles i decied to keep the D30/35 because a guy in my club had stock ones on his TJ for years without issues. he was going to all the same places I planned to go so I figured if I beefed up the ones I have and don't bounce the jeep or drive aggressively I should be more than fine. Hopefully this perspective helps.

 

Thanks for all the info guys. Here are a couple pictures where I'm at with my axles. What was suppose to be a 15 hour lift kit has turned into an experience to say the least. The front axle housing was so corroded it was easier to cut everything off and buy the Iron Rock truss. The rear housing spring buckets and brackets were in much better shape so I built a truss of my own making and added some doublers to the arm brackets to beef it all up. So many things wrong, corroded or rusted through. My sister bought this ZJ new in Ohio, after a few years exported it to Scotland and about 10 years ago it found its way to SC were I stored it for her to use when she came to the States. Last time she was here she gave it to me. I'm finally on the build side instead of the inspection tear apart and fix side so I'm getting optimistic. Hopefully I'll get to see some of y'all on the trail by Spring