1996 Honda Civic Automatic Feel Vibration Accelerating Normally 40km

i have honda civic 1996 automatic , the problem is i feel a vibration when going accelerating normally from 40km to 60 km and the vibrations goes away after but if i step on hard on the gas no vibrations happen , in the mean time i hear a noise coming out from the wheals as i spead up ........... So 'ld you please help me , thaaaanx