so just replaced my cv joint and hub due to the hub being bent and cv joint had a hole in it. The day before I replaced them I drove home and downshifted into 2nd gear and the whole car shuttered, now I test drove the car and it is still happening. When I accelerate I hear a pretty loud whir and it kinda feels like my differential. Any thoughts?

 

have you checked your diff fluid? also, do you feel any vibration? have you inspected your u-joints?