Originally Posted by Palmo' post='428030' date='May 24 2007, 11:51 PM

To be honest, this is one aspect of the car I am finding very disappointing. I've had my 525d M Sport for approaching 4 weeks now from new - car is fitted with 19" 172M's with non RFT's and without AS. During this time there has been more than a fair share of 'windy' days. On a calm day the car drives flawless with impressive refinement and stability. Introduce even a small amount of wind though and this all changes. I've even had one situation where I was struggling with the car at 65mph - granted this was on a very windy day. I am very used to driving long distances and have covered up to 40k miles in a year before now - so have a lot of motorway experience.

Surely there is a considerable design flaw somewhere for the car to be effected to this level. I have driven on the days affected observing vehicles in front, and as I have been blow from one side of the lane to another, I have seen cars that are 10+ years old 'bangers' that are completely stable. On one such day I even went back out for a drive, after returning home, in one of my other cars to see if the wind was so severe and guess what, no stability issues.

I still love the car but this is really unacceptable in a car of this value and reputation. The car is definitely worst effected by cross winds, and not so much by head-on or tail winds. Could this be down to the fact that the car is relatively large i.e. a large area for the wind to get hold of, but is combined with a relatively low kerb weight? I notice that the cars underbody is completely covered (with the exception of the exhaust / transmission tunnel) giving the underside a completely flat surface - I would have thought this would aid aerodynamics?