I want to run 37" tires with a lift, so first what size lift? Then, is it at all possible to run them with stock axles? I use my jeep for some moderately bad roads and some pastureland driving. Can someone explain what I'll need in laymans terms? I've read and read other Q&As but I can't make sense of them

 

Read the stickies at the top of thread

 

As noted, start with the threads stuck right to the top of this modified area. You will find info on lift height vs tire size, the various lift and steering components, gearing suggestions, etc.

Can you run 37's on un-modified axles? Of course. Will you bend or break? No clue, roll the dice. Plenty of threads discussing this, with people on both sides of the argument. Do a little research into the various options, (C gussets, truss, inner sleeves, outer sleeves, skids, hd mounts, alloy shafts, hd ball joints, etc), price them (with the labor for install if you don't weld or don't want to do it yourself, since many of the prices you will see posted are parts only!!), then factor in a realistic vision of your use and needs. Bottom line is that no one can tell you if you will or won't have an issue, so no one can tell you what 'you' need, or don't need.

One of the many, many threads that will help totally confuse you...
Poll D30 w/ 37"^ tires - View Poll Results