I'm assuming you are currently running turfs..
You should have no problems pulling an aerator with turfs.
I wouldn't think it would pull that hard.
I have a 48" Bannerman and i was surprised at how hard it pulled. Like you, i figured it would be like towing a finish mower or something but those spoons really do add some resistance. Mind you, i have alot of clay and my tractor is only 21hp but I was surprised none the less....