I have heard that when people change out the head unit of GM cars that have RDS(radio data systems) they experience problems with functions in the vehicle that are also controlled by this system. My 2002 Xterra SE has RDS and I am wondering if anyone has heard of any problems with changing the headset. If not, is it possible to add a sub to the stock headset(6disc) with a converter.

the problem with the GM headunits on newer vehicles is that GM runs a lot of the vehicles functions through the receiver(door chime,oil change reset, etc.), undoubtedly a ploy to make it harder to add aftermarket products. you even have to have the ecm reprogrammed if you add factory foglights after the fact, otherwise they will not be "recognized". i think that some other auto mfg.s like Honda do it as well(they run the power door locks and alarm through the factory head unit). RDS is a radio protocol. its designation has nothing to do with the problems that GM vehicle owners are encountering and you will not encounter similar problems with your Nissan. i have included a link at the end of this post that should help clear up any questions about the GM receiver situation.

http://aampofamerica.com/bestkits/news_best_gm_doubledin_0601.asp

oh, and it is possible to add a sub to the factory receiver with a line converter. good luck

You'll need an amp, but the stock head unit is fine. Just do a search in this forum and you'll see detailed instructions.