Did some maintenance on my 550i and now it drives worse

[Mervon]

My 08 550i M sport just hit 121k. My car was feeling loose and unstable when hitting uneven surfaces so I knew some bushings needed to be replaced. Front control arm bushings were shot so those were taken care of, plus I replaced my rear tires with UHP Federals. The front feels tight now but at freeway speeds the car is so touchy. A slight adjustment on the steering wheel and the car jumps to the side. It's so bad that taking an onramp at speed will make the traction control light flicker. Could the different treads from the new Federals on the rear really cause a driving experience like this as I still have Michelins up front? The tread patterns is very different between the two but I feel like I have drove many cars with different tires without ever noticing. Any other ideas what this could be?

[M5Rick]

Best stick to original Michelins,any others just don't bond with BMW characteristics.
If the bushings were not originals then again,stiffer ones will give it a spooky race car feel.

[6ixSpd]

Sounds like you desperately need an alignment. Anytime you change suspension components, it's a necessity.