Hi guys, I just had a local mechanic replace my brake pads and rotors to brand new in the front and the pads only in the rear. im experiencing extreme shuddering and heavy vibrations under highway speed braking from the truck. My cousin who is workin on his ASE certification says that my brake rotors are warped and that typically the shuddering is caused from the front brakes. I wondered how could this be when I replaced both the front pads AND rotors, and assumed only the rear rotors needed to be turned, but he then said that cheap pads/rotors will also cause this issue. Could the rear rotors ALSO be causing the shuddering here? I would hate to have the front rotors turned when its not necessary to do so. Also, i did buy some of the most inexpensive (still in my opinion of good quality) pads/rotors I could afford. I didnt see anything wrong with them, he said since they were not OEM they may not have been made of the same soft tensile compound required to make the truck brake smoothly. I guess my question is, should I shave the front and rear rotors or just the rear? the pads are new front and back and rotors are new front only.