Ok, thanks for the reply tireguy. I ended up calling tirerack and talked with one of their people. They claim there shouldn't be a problem mounting 16's on my G6 even though it came with 17's. My question is, is there a difference in the rotor or caliper size between a car that comes with 16's rather than 17's? Or any other problem other than the possible 3 MPH difference that Conrads tire center claims i'll see by going with 16's? My main concern is i don't want to drop $900 between tires and rims only to put them on and have a clearance issue or bolt pattern issue or any other problem. Thanks again!
08' G6 Sedan, 2.4L Auto 174,800 miles