So I'm trying to make my DD a little more capable as my other rig is a trailer rig only. I have a 92 i6 HO, auto, np242, c8.25 rear 3.55 gearing. I'm about to put on a RE 4.5" lift and know I will need a SYE. I have a parts jeep with a good np231. I'm debating on if I should do a hack & tap on my 242 or swap it with the 231, I don't live in an area where I need full time 4x4, I lived in Montana before and loved having it, but I don't have a need for it now. Is the aftermarket support for the np231 worth the swap? And is it as simple as just swapping the tc?

Also I've realized I need lockers. Support for the 8.25 for lockers is lacking it seems... Should I lock the front d30 or the rear 8.25 first? I would get select-able lockers or air lockers. I also have an 8.8 with welded 3.73 gears I could swap in (and regear the front), how bad is driving in town with a welded rear end?

I plan on running 33's with the 4.5" lift, will stock 3.55 gearing be bad with 33's? I'm currently on 31's with a 2" lift...

As it sits now...

Swap the in the 231. Very easy. Stay away from welded if it goes on street. Yukon just released a 27 &29 spline spartan for the 8.25. Im doing Spartans front and rear. Easy to dd but cheap too.

33's are gonna suck on 3.55's but you can do it. I wouldn't recommend it, especially on a dd. I'm at 4.5"-5" and didn't want to re gear so Im running 31's and its actually really nice. You can flex like crazy with no rubbing and the gas mileage/power is still pretty good. Once I get my new tires on ill throw up some pics. My fenders are trimmed like yours but I don't have the nice flares

Oh and get a 29 spline Spartan and swap your shafts over to 29 spine. A 29 spline 8.25 is a solid rear axle

The 231 has tons more aftermarket support and if it's from a 91 and newer model it'll bolt into your 92. 90 and older have 21 spline inputs as do 4 banger models and 91 and newer autos have 23 spline.

deff make the switch to the NP231. IT is a stronger option than the 242. If you are only going to lock 1 axle go with the front first. You will get a lot of pull from a locked front. Ive always been warry about locking a 8.25 because it is a c-clip axle. With the added torgue fro the locker you are more likely to snap a axle shaft. And with c-clip axles there is nothing holding your wheel in place if you break a shaft.

If I were you, I'd take that 8.8 and lock it with a lunchbox locker (they're cheap and decent on the street) to get the welded spider gears out of it. Then gear it and your d30 to 4.56 and run 33s. Leave the front open or put a selectable locker in it. it'll last longer on the trails if you beat on it any. Put in the 231 and possibly a sye if you need it.

I run that exact same set up except my d30 is locked with an aussie. It'll go a good amount of places and is decent on the street. It's a pretty reliable set-up and allows room for running 35s in the future.

^^^What he said. If you must have selectable lockers, E lockers are the cheapest followed by the auburn ected then the ox an the air locker. Air lockers are insanely overpriced themselves but you also have to get an air supply for them which is pricey in itself. I would put a lunchbox locker in the rear and save the selectable for the front. There is a night and day difference in having just a locker in the rear over stock. You can go places in 2 wheel drive you couldn't even go in 4 wheel drive before