You were told by a mechanic that a 1999 Toyota RAV4's timing belt needs to be replaced after 72 months you thought it was 90000 miles What gives?
Timing belts should be replaced about every 40,000 miles or so
more often under extreme conditions, they can and WILL fail with no
more then 20,000 miles on them. With many newer motors they are
zero clearance which means if the belt goes while motor is running
it will bend valves , that will be adding 500 to 1500 dollars to a
TIMING belt job