So you need a 4x4 4.0l 5R55E no conversion is possible for that............well you can but would cost a bit more than a full rebuild, lol
Yes, lower miles is always good on a use automatic, but watch out for VERY LOW miles, it means vehicle sat for long periods, either broke down or not needed, the seals and gaskets dry out, so when you start to use it regularly you get leaks and with an automatic that means problems
2011 Under 100k would be OK
2011 Under 40k would make me wonder