Here is a question that comes up from time-to-time when a Tire Rack customer buys a vehicle with the performance or sport package and doesn't realize the effect the sport suspension and lower profile tires will have.
"I have a 2005 Cadillac CTS. The ride is very rough and I think it might have to do with its low profile tires. Can regular tires be installed on the car instead of the low profile tires? If so what tires would you suggest?"
This CTS came equipped with the Luxury Sport Package and a 225/50R17 tire which isn't a really low profile tire, but the ride would not be as good as the Luxury Package and a 225/55R16 tire.
Though low profile tires do play a roll in ride qualit, you can't place the blame on them for everything. The Goodyears (225/50R17 Eagle RS-A) that came on this particular Cadillac are not one of the smoother options. An aggressive alternative would be to downsize to a 16-inch tire and wheel (16x7 wheel and 225/55R16 tire). Another option is to select a better riding 17" tire from the Grand Touring All-Season category.