Hey all,
so I’m getting ready to start the leap
into a crawler. So ideally, the plan is to go with an LS3 swap and keep the np231 and bolt that all up to a TH350. Ive heard that the 231 bolts up with an adapter but if it’s not the greatest idea I’d love to hear what you guys all have in mind. Another thing I plan on doing is axles and somewhere along the lines of 40’s+ in tire size. Does anybody have any idea on what kind of axles are ideal for this kinda swap? I’d rather not do a D44 but I’m not afraid to run one I’ve just heard that it’s a pointless “upgrade” from the stock 30 on the front. But as of right now I’m sitting on a 4.5 short arm and 33x11.50s, I know I’m gonna have to y link it and maybe go just a tad taller? These are all ideas and any input is great, thank you guys and if you all need more details just lemme know. PS. I plan on beating it like a buggy so sturdy equipment is ideal but not at an outrageous bill. Thank you guys, I appreciate it!

 

turbo 400 is a stronger tranny, the 241 from a tj ruby is a stronger transfer case w/ 4.1 low range, dana 60's will be needed for tires that big. whats a outrageous bill to you ? this wont be cheap.

 

You can get a set of Super duty axles for pretty cheap, used 4x4 fleet trucks go for $1000-1500 you can use the axles and the NV271 transfer case.

 

A pair of superduty axles is probably the easiest swap since you can get a weld on truss for the front from places like Artec and others. Though you'll probably want to upgrade to a long arm lift and go up to 6 inches of lift or more. Almost any rear axle is easy because it's just spring perches and shock mounts. For 40's or bigger you'll really want hydraulic ram assist steering if not full hydro steering.

The 231 isn't a bad case but the 2.72:1 low range is a little limiting for a crawler. A lower low range gives you the option to finesse over obstacles rather than having to rely on the skinny pedal all the time. The TJ 241OR from a Rubicon with the 4.0:1 low range is a good upgrade if you can find one for a reasonable price. The 271 is a burly case but there aren't as many adapters out there and it still only has the 2.72:1 low range. When it's all said and done, it may be just as easy to order an Atlas II with the low range you like (I'm a fan of 4.3:1) and set up to just bolt to whatever transmission you go with. I found that a Rubicon 241OR with an adapter was going to be about as expensive as an Atlas but the Atlas is a lot stronger than the 241 and gives you some additional options like twin stick.

 

Thank you all for your help, like I’m expecting a few grand but I mean it’s a pos that I just wanna reliably have fun in haha. But I’ve heard of the atlas and atlas II and the tunable ratios that come along with it and I’ve considered that as well! And I’ve heard lots about the f250 axles and I think that’s the route I’m going to go with when it comes to axles. Definitely gonna stick with an ls for the swap, I know it’s common but I like idea of how easy they are to find, easy to work on and for the most part are very buildable.

 

There's something to be said for doing what everyone else does. A lot of people have posted up how to solve problems and, in some cases, there are bolt-on or weld-on parts you can use instead of having to fab it up yourself.