A suspension system in a motor vehicle has a suspension including at least a resilient member extending transversely of the motor vehicle and having one end operatively coupled to a knuckle, the resilient member supporting a vehicle body of the motor vehicle, and a detector disposed on the resilient member for detecting at least one of a change in a load and a change in the height of the motor vehicle from the ground due to an external force applied to the suspension. The resilient member comprises at least a leaf spring, and the detector is attached to the leaf spring for detecting a strain of the leaf spring due to flexing thereof. A calculator is provided for calculating at least one of a vertical load applied to a road wheel coupled to the knuckle and a displacement of the road wheel with respect to the vehicle body based on a change in the strain detected by the detector.