I am having a similar issue after installing 2.5" rear lift blocks and a set of Bilstein 5100 set to 1.85". Feels like bad shake while braking, felt through pedal and stearing wheel. Starts at around 70kmh very slightly worsening as I get closer to 30Kmh. I believe my problem is pinion angles do to the wrong style block?? (all installs were done by a shop and it did receive an alignment. Also has been back and everything checked over)