You can do this with the Embedded Event Manager. These applet policies should work with just about any modern IOS. This will watch GigabitEthernet0/0 to see if its utilization goes over 85% and stays there for five minutes. If it does, an EEM trap will be sent.
event manager environment q "
!
event manager applet watch-interface
event tag e1 interface name GigabitEthernet0/0 parameter txload entry-op ge entry-val 204 entry-type value exit-op le exit-val 204 exit-type value poll-interval 10
event tag e2 interface name GigabitEthernet0/0 parameter rxload entry-op ge entry-val 204 entry-type value exit-op le exit-val 204 exit-type value poll-interval 10
trigger
correlate event e1 or event e2
action 01 cli command "enable"
action 02 cli command "config t"
action 03 cli command "event manager applet notify-interface"
action 04 cli command "event timer countdown time 300"
action 05 cli command "action 1.0 snmp-trap strdata $q Interface GigabitEthernet0/0 has been above 85% utilization for five minutes$q"
action 06 cli command "end"
!
event manager applet reset-int-watch
event tag e1 interface name GigabitEthernet0/0 parameter txload entry-op le entry-val 204 entry-type value exit-op ge exit-val 204 exit-type value poll-interval 10
event tag e2 interface name GigabitEthernet0/0 parameter rxload entry-op le entry-val 204 entry-type value exit-op ge exit-val 204 exit-type value poll-interval 10
trigger
correlate event e1 or event e2
action 1.0 cli command "enable"
action 2.0 cli command "config t"
action 3.0 cli command "no event manager applet notify-interface"
action 4.0 cli command "end"
