Try to drive it on the highway for about 30 minutes before you buy it. When you slow down, try to make sharp turns on the pavement. If it is buckling and turning rough, you have a bad viscious coupler (see the articles about swapping a t-cases). Plan on $1500 to fix the NV249, or maybe a little less to swap to a 242 and have the 2wd option.
2003 Dodge CTD Quad Cab 4x4, 320k miles and counting
98 ZJ Limited, 5.2L, NP242, Jet Stage II (worthless), K&N, 245/75-16 BFG KO's
89 XJ, stock
79 CJ7 - Options included ripped soft top, leaky 4.2L (5qts/week), ripped seats, 33" tires, bondo & gray primer