How can I reduce some of the road noise in my 2009 HHR?
I get a lot of tire road noise on the free way
2 ways, next time go with a different tire, less aggressive/softer tread. or buy the rolls of dampening material, you install behind each panel, remove the panels, roll the fabric out, and cut it. that works good too. run your hands along the tires in either direction, if half or so is rough they can be "alligatored", which will cause noise,
if the pavement looks grooved, i'm doubting u can do anything. certain areas are grooved for grip/traction.
i have just the plian hhr. i been looking at new ones and the ones carpeted in back are so much quieter than mine. and yes tires makes a big difference
try throwing a blanket down in the back- it will absorb some of the noise instead of just the hard plastic back there.