I have a C5 2 litre HDi Exclusive Tourer, and yes it has the same problem, which appears to travel up through the steering column. It has just been in for its first service and the dealer (not the same as purchased through) just smiled when he heard my complaint and saw the 18" wheels, and told me that they were notorious. To be fair they did road test the car and check the bearings but found no faults. Apparently the garage owner always runs top of the range C5s but insists on having the standard wheels and tyres fitted to keep the noise down! Such a pity because it's a great car, despite a couple of other problems, and very good value for money.
