Rear Suspension problems of the 2008 Mazda Tribute

The contact owns a 2008 Mazda Tribute. The contact stated that the back end of the vehicle sways violently when driving over bridges with iron grates. The failure causes him to grip the steering wheel tightly in order to maintain control of the vehicle. The failure was noticed the first day the vehicle was driven on the highway. The speed was unknown. The current and failure mileages were 705.