1995 Honda Accord humming/grinding noise at 60mph

Hi,
I have replaced the front left bearing with local mechanic since its little shaking. When picked up the car at low speed every thing was good but as I reach the noise ( wheee, wheee.) From the front somthing griding or rubbing -every I touch 60+ I hear the noice. Took back to mechanic - he says the transmission noice and nothing to do with the bearing that he changed. I wach him change the bearing - he did the work professionally ( I understand the Auto mechanics little). Any suggestion will be great help
Thanks
Brandy