I've noticed some erratic vibration in my 940 sedan steering at higher speeds (70mph plus); I've recently had my snow tires fitted and pressure checked so do not think problem has come from tires. With hands off the wheel (on a clear road of course), the steering wheel vibrates and when driving, it feels as if the front wheels are almost wobbling out of line. At slower speeds on normal road conditions, there are no apparent problems (no pulling to one side and car drives as normal).

Should I be looking at wheels/bearings or steering/suspension first?

Thanks..