I recently turned 60k on my 2000 X. I am happy to say that I have never had a problem with my Xterra. I change the oil every 3k and have a K & N air filter.

Is it time for new plugs and oxygen sensor?

My only gripe is that gas milage sucks but its what's posted 18-20 highway. I get less as the speed limit here in Florida is 70 so everyone cruises at 80 or so...