CMcD26

Truck has 102,000 Miles, phaser issue, exhaust leak, and have not replaced spark plugs yet (haven't had time to adress these problems yet) I need some help figuring this one out, ever since the temperature has dropped.. my truck hums very loudly when I accelerate at speeds of 55+ or while going up a hill. I can feel loss of power as well as a vibration on my feet from under the floor boards. I have a K&N cold air intake with a Ram Air hood, could this be too much in the colder weather?