Hey guys, so.... On my '97 Chevy C1500 am on the highway at about 75, been noticing a vibration coming from the rear. Tilted the drivers mirror down and in to see the rear wheel, and noticied it is not running true. Pulled over and checked the lug nuts etc, which were okay. Anyway, it seemed as if the rear wheel is buckled. Got it home okay and had a good look at the rear end. Axle bearings ok, no noise at all from the axle, but i notice the flange on the drivers side axle shaft is not running true. I can also see what looks like a crack where the flange joins the shaft (see pic below) Does this look like a crack to anyone? or just where the brake drum has been in contact with the flange? Am obviously worried about it coming off at some point. How are these flanges attached to the shaft? i cant see anything on the rear of the flange that looks amiss, the axle shaft itself apears to be running true into the axle tube bearing, just the flange. Here are a couple of vids of it running so you can see how bad it is, drivers side (the worst): and And for comparison, the passenger side: Basically what i wish to know is, how worried to i need to be about this?