vibration when brakes applied from hwy speed

2001 Tundra 4X4 Automatic. When slowing down after hwy speeds feels like wheel hop or vibration when brakes applied but brake pedal and steering wheel are smooth with no pulsations or vibration. Only does it after hwy driving. Been doing this for 8,000 miles and has new tires so that is out. Doesn't get any worse???

Problem seems to be solved Toyota dealer turned front rotors then test drove then put an on car turning lathe on and turned them again and the second time it seems to have gotten it all out. Very strange as it did not have the pulsation you normally get with a warped rotor. They couldn't explain it either. So far So good !