Toyota Repair: Front end grinding and shaking, brake lathe, tacama

Question
Toyota Tacama 1998, 4x4, extended cab
4 cylinder with 89,000 miles.

The front end on my toyota is shaking and grinding.  It shakes when I brake and especially when I am going down a hill and braking.  The grinding sound from the tires happens when the car is moving forward, it did not happen with the older brakes pads I had on.  But I did replace the brakes pads about two months ago and at first I did not hear as much grinding as I do now.

I also got new tires about two months ago as well.  

Answer
The brake rotors are probably warped and need to be replaced, were the brake rotors resurfaced on a brake lathe when the pads were replaced? The rotors may be below the minimum thickness and I recommend having the rotors measured to see if they are within the specs and also have them checked for runout.