I have 2009 Dodge Grand Caravan with a 126000 km and with a 3.3 L engine. My question is as I drive and speed up, there is a humming sound coming from the front and there is something like holding from driving fast even I step the gas pedal all the way down on the floor. The tires has been rotated because I thought it was the one making the sound but I can still here the humming sound. The sound is much stronger when the windows are closed. What must be the problem? Thanks a lot hoping for your most appreciated reply.