Barry, nice web site.
Drawing on your expert experience do you have any suspicions on what would cause the roar of the Hankooks to disappear completely when they are replaced by snow tires that should be a little noisy but aren't.
A simple observer like me is convinced that the problem is the tires. I will see that they are rotated when they are put back on the car this spring but what do I do if the roar returns? Replace them at my expense?
Thanks for your time
There are parts of this that do not make sense.
As a general rule, OE tires - the tires that come on new vehicles from the factory - are generally designed to be quiet - ish. I can not imagine GM allowing a basically noisy tire through their process. On the other hand, I gather that this vehicle was designed in Korea, so maybe the GM engineers didn't have the power (or didn't know about it) to overrule the Korean design team.
Another thing that doesn't make sense is that the winter tires are quieter.
So is it possible that the noise only appears bad on one particular road? That has been known to happen.
If that is the case - and even if the noise is there pretty much all the time - then, yes, you are going to have to replace the tires. I would start with the dealer where you bought the car. If they won't help you financially, then call Hankook's 800 number and talk to them.