They are both ax 15 trannies. Jeep went to the nv4500 in 2001? Both are np231 T-Cases. I know the main shafts are a little different. The YJ shaft has 2 pressed bearings that 97+ jeeps do not have, but this should not make a difference, The portion of the main shaft that goes into the transmission are the same. If I was you, I would try to locate a solid np231 out of a YJ only cause you know it will fit! But unless someone tells you otherwise, I am only thinking it can be done easily.