Reverend D21 wrote:make sure it has the updated rear pumpkin cover w/ cooling fins on it. The early ones didn't have this and roasted rear ends frequent enough during towing.
This^
I work for Nissan and to be honest you don't even have to tow for it to fry the rear end without the fins, i've seen plenty of Titans without any tow equipment come in with welded rear ends. Also be VERY careful to feel out the transmission, they often have issues with slipping or erratic shifting and the trans coolers have their own special TSB for failure lol. So its a MUST to check the color, and smell of the trans fluid.