For front suspension systems of certain 2WD vehicles, (1) the torque of the bolts securing the lower arms and the lower arm ball joints may not be sufficient, due to improper installation. If this problem is left unattended, the bolts may loosen, and in the worst case, they may break and cause the vehicle to stall. (2) for vehicles on which RJ-1821-0 measure was carried out, the the torque of the bolts securing the lower arms and the lower arm ball joints may not be sufficient, due to the improper replacement method done for RJ-1821-0. If this problem is left unattended, the bolts may loosen, and in the worst case, they may break and cause the vehicle to stall.