On certain school buses, the lock nuts for multiple front and rear suspension and steering parts may not have been manufactured correctly. As a result, the nut(s) could loosen. If this happens, there could be a sudden change in vehicle stability and/or a loss of steering control.
A loss of steering could create the risk of a crash. A sudden change in vehicle stability could cause a loss of control and increase the risk of a crash.
Navistar will notify owners by mail and instruct you to take your vehicle to a dealership to replace the affected hex flange lock nuts.