I'm talking driving up to Elbe hills, driving down to moab, driving to the rubicon trail system, wheeling there, and then having confidence in your rig to drive home.
Nice line-up.
Knowledge of your rig that comes with years of running it - I'm talking about understanding the soul of your rig.
Correct. I feel like seat time is often overlooked. It's the best way to get to know your rig, and start to understand what it truly is capable of.
Here's my .02 on what makes a reliable/capable rig, and what I built the Nail Salon around:
Motor: With a 4.0L, mileage doesn't really matter. I drove my last Jeep to Moab and back with 290K on the clock. Just make sure you stay on top of maintenance. If it's not at 100%, why take it out on the trail and risk having issues? Also, make sure your cooling system is adequate. There's nothing worse than having overheating issues on the trail. Slow speed crawling, and bombing up hill climbs will heat things up quick.
T-Case: The 231's are pretty forgiving overall. Personally, I'd go with a full SYE and not a Hack-n-tap. Knowing I have a 32 spline output on the t-case with a yoke and strong driveline is a peace of mind.
Axles: Again, it's about peace of mind when on the trail. If you're sticking with "stock" axles I think 33's are perfect. Anything bigger is just going to put more stress on parts, and risk breaking more junk. Re-gear for larger tires, and to make driving to and from the trail more comfortable (4.56, 4.88). This also helps with the cooling system. I'd recommend a full case locker too, just because the stock carriers can become the weak link. Knock on wood I haven't had any issues with stock 297X shafts. I like to tack weld the caps in just to help keep the caps in under high torque. Use only Spicer u-joints, any other parts store brand is junk. You can add a truss, sleeves, and other bling parts if you wish, but really it comes down to a good set of gears, lockers, and no worn out junk parts (ball joints, u-joints, bearings).
Steering: There's a ton of aftermarket products available, and they are all going to do a fine job on the trail. The difference oftentimes has to do with their street manners. The 1-Ton Inverted-T is a tough setup, but it has a tendency to create a dead-spot and "roll" on the road. I'm a fan of keeping the stock geometry for the street. Either replace the wimpy stock tie-rod with a heavy duty since the stock drag link is pretty tough, or go Currie and be done with it. The Currie system is just beef, and drives like stock on the street. If you're steering is feeling "loose" it's likely going to be a worn TRE. The mud around here likes to make it's way into parts and wear them out.
Suspension: This is one category where you get what you pay for in my opinion. Don't cut corners trying to save a few bucks. The first is a good quality track bar, setup for double shear. I've seen way too many junk track bars taco on the trail. No stock control arms. A lot of people try to get by with just aftermarket lowers leaving the uppers only to find out they will buckle on the trail. Aftermarket short arms are super cheap. Don't lift the rig sky high either. Stability and low center of gravity are good things. Springs are springs, but you do get what you pay for in my opinion (Rough Country vs Deaver).
No lift blocks!
Armor: More armor the better. Skid plates are essential for protecting the drivetrain, and gas tank. You won't be able to drive home with a t-case split in two. It's another peace of mind knowing that the horrific noise of steel on rock is actually a good thing. I'll also include a solid steering box system with this. Something that ties into the bumper, and maybe a box brace for added strength. I've seen a few boxes rip off the frame on the trail, or at least add to cracking (mine included).
You can create a solid rig for cheap, it's not a money thing. The key is just staying on top of maintenance, and getting some seat time with your rig. I really don't understand the whole trailer queen thing. Why trailer your rig to the trail expecting to break something? I hate wrenching on my junk, and I sure as hell don't want to do it on the trail.