Didn't you install a rear adjustable track bar? How bad is the rear pinon angle? You having any issues running the OEM axles? Two of the codes makes sense to me if your axle was binding up real bad. C1015 is wheel speed sensor correct? U0415 has something to do with the ABS correct? If that's the case and that tires was way off on reading because it was binding up it would throw codes. Not sure but that's my best guess right now.