Hope to provide a little more info here,According to my 94's owner manual, the timing belt doesn't need to be replace until 105k miles, so i guess only the 93 need the first TB at 60k miles.If you want to do maintenance or repair youself, check
http://www.infinitipartsusa.com for OEM parts first, cause they seem to have good price for our J compare to other dealership.FYI, a timing belt kits for the J cost ~$320a J30 OEM Shock Kit, 2 front OEM strut cartridges and 2 rear OEM shocks cost ~$490Transmission service kit, pan gasket and filter cost around $40Tranny cooler from summit racing cost ~$60