Water in radiator not getting hot

1999 durango 5.9l

Water in radiator not getting hot
Hose on top of thermostat is hot
Replaced thermostat and water does pump into radiator when it opens
Line going into heater core hot/warm hose coming out cold to warm at best, heater only blows luke warm.
Temp gauge In car reads anywhere from 180 to 195 never gets any hotter

Any ideas

clogged heater core??

thats what im thinking just havent had a chance to backflush it yet, would that keep radiator for getting warm 2

im thinking it will, be careful on a backflush it may end up costing you more than a core....