i had similar issue,
thrust arm bushing, bent wheel, unbalancing tires could be the reasons.
I had bent wheels, worn out thrust arm bushing.
they both covered by dealership tho. Funny thing is my indy mechanic found out worn out thrust bushing when dealership told me they couldn't relocate worn out bushing, but I told them drive the car and they finally agreed to change the bushing.
RPI | H&R | 2008 e86 M coupe
KW | VOLK TE37SL | RECARO | PE - 2008 e92 335xi