Feeling unstable on high speed

[augist]

Hey all,

just got my first bimmer and I absolutely love it. However I started noticing instability on speeds between 70 - 120kmh. On straight roads car feels floaty and is swaying left and right. It's not very bad, but I still have to continuously correct it. Friend says it's just a bmw thing, because steering is very sensitive to the road. But honestly that's the exact opposite of what I expected from bmw... What are your opinions? Maybe soft winter tyres, bad alignment or truly just a bmw thing?

[relative4]

Could be struts or thrust rod bushings. What does it do when braking? With the front wheels off the ground, look for oil leaking from the strut seals and see if you can move the thrust rods by hand.

[gusm325]

The old Bimmers required that the "bushes" where pre-loaded prior to torquing the bolts or they felt "very funny" someone could say unstable.
I don't know about these new ones, (even though if you jack up the car for any work, when you place it back down the wheels on the ground they still look all out of whack as the older models did).
If you have had any suspension work done lately it could be as easy as re-torquing suspension bushes while the car is on the ground or better said on it's own weight...
Perhaps you have tire issues... Winter tires...

Maybe the E90 gurus can shed light on this.

[Critter7r]

The OP's problem can be caused by no less than a dozen issues.

Without seeing the car, I think the following info would be the bare minimum needed to being to diagnose this over the internet ...

How many miles?
Tire size? Brand? Tread depth? Pressure?
Any suspension work done previously?
Accident history?