More than 50% of the time, when slowing down from 40-50 mph, there is a shaking or shimmying. It feels as if its in the steering, but the alignment is good (can let hands free of wheel and it stays true) and just put new tires on it.but you can feel the shaking, but only while braking. I had the front brakes replaced at 44,000 by the dealer.What could this be?