I just had my whole driver side power mirror replace due to a accident. Now during driving, i find the image on the mirror is shaky. I check the mirror is not loose from the actuator and all the screw are secure. Does anyone knows what wrong

 

More then likely if the mirror is not oem then you will have to just deal with the shaking...I've seen plenty of aftermarket side mirrors do this..try moving the mirror up and down and left to right with your hand and see if that helps..other then that there's not much you can do!!