In general most vehicles recommend changing them at 60k, but the newer pathfinders and a couple other Nissan vehicles recommend them changed at 105k. From many many others that have changed the timing belts themselves this is a conservative mileage and you should be fine changing it by then, belts changed at 130k still had plenty of life from the pictures. If you want to research then look at some of the offroad Nissan sites that have 1000s of members and tons of maintenance history, one thing you won't find is anyone that blew a timing belt < 105k or ever as far as I have been able to find. Check out
www.4x4parts.com,
www.nissan4wheelers.com,
www.nissanforums.com,
www.nissanoffroad.net.