Timing Belt

I have a 96 Maxima SE w/97k mi. When should I get the timing belt replaced?

NEVER! Your car doesn't have one. The VQ motor has a timing chain which is supposed to last the life of the vehicle. Some problems have been reported with the timing chain tensioner. When that goes, you will hear your timing chain chatter when you start the car in the mornings.

Other then that, no maintenance is required.