Id go with the XJ personally, I recently just got rid of mine. And despite the reviews of the Dana 35 several people wheel them without an issue, its when you start throwing 35s, lockers and do some tough trails that you will run into some issues. There are pros and cons to both, with a family Id do the XJ, I love TJs as well so it wouldnt be a bad option at all, especially considering maintenance is done from the sounds of it. Does the TJ have new gears?! That would be the other thing going to larger tires you'd have to regear that like the XJ