Originally Posted by Fojo

i have been having the same issue. i get loud bangs over manholes on my right rear, but otherwise the car rides just fine. im not convinced my rear strut is bad just yet. im thinking subframe bushings. or i will at least rule them out by changing the first... as for steering wheel shake at 55-65 and rattle over bumps.. i have dealt with that for about 2 years i haved one **** ton of research and taken it to lexus multiple times and every time they said everything is good. so i took it into my own hands.. last weekend i replaced the steering rack bushings with the daizen poly bushings from amazon. BAM the rattle is completely gone, and the shake is 90 percent gone. after inspecting my LCAs, they are shot too. turns out the steering rack bushings were ovalled out, assuming from the LCA bushings being bad and allowing the shake and after awhile, it compounded. i bought the LCA bushing subassemblies for the IS and will be changing those on monday, then i will write a detailed post on my journey. so first, check those steering rack bushings, and those LCAs. i will be looking into subframe bushings in the near future. good luck!