Well, couldn't fit the Duratracs on mine with the CCM 2.5/1". Not sure why, but I would have had to do some major trimming to allow for wheel travel. It wasn't just rubbing behind the small black piece on the bottom of the bumper, it was rubbing a good 3" above that. Any travel up and down would have made it worse. Not sure if there is a difference between the 08 & 09 that made the difference. I did notice the small black piece on mine looks different than your 08's.
Ended up putting on a set of 285 BFG's. Will post some pics later.
Could it be because, he has a Z71, which has different shocking and different wheel flares? Just throwing it out there.