i have a 2000 neon and i hear a humming/rumble sound coming from the rear of the car. it does this until about 60km/hr then it is quite. any thoughts in what it might be?

Could be rear hub bearings though unlikely. Loose or missing rear bumbper brackets, or your exsaust system is touching metal.
Best of luck Wayne

it was the right read hub..125 for parts 2 minutes to replace.