Question to OP... Is your car's steering very touchy? Do you have Active Steering? Have you driven another comparable 5 series with same Active/No active steering to see how it drives? Is your steering wheel cocked a couple degrees off center? I'm starting to think perhaps it's your SZL (Steering angle sensor) but need more symptoms.

 

so its been awhile and i replaced and balanced all four tires. shaking got a little better but its still there.