If you can feel the crosswind while driving, it is not slight. Been driving SUVs for 14 years now. It's normal on a tall car to feel a jolt sometimes - think about all the times you don't feel it - how would you know the difference that it's stable one time and not another?

As far as making it sway side to side... is it making you adjust once back to your lane or are you really fighting the wheel left and right to get back straight?

__________________
'08 X5 3.0si - Alpine White / Saddle Brown interior
Specs: Sport Pkg, Premium Pkg, Tech Pkg, Comfort Access, Aero Kit, Style 433 staggered 20s on Conti DWS
Mods: Carbon 35 tint, LED angel eyes, GP Thunder 7500k fogs, H&R 20mm/25mm spacers, clear reflectors, gunsmoke-tinted taillights
Coded: Digital speedo, windows/sunroof/tailgate close via keyfob

X5 pics at Flickr