Parallelism control tool and method for dual-front-axle vehicle

The invention provides a parallelism control tool and method for a dual-front-axle vehicle. The parallelism control tool and method can control parallelism of dual front axles on-line in a highly precise manner. The control tool comprises a fixing nut, a magnetic claw, a C-shaped plate, a reception target and a laser emitter. Two tools are symmetrically designed and fixed on transverse plane bolts of front-axle wheel hubs; two laser beams of the tools, facing each other, are emitted to the targets; straight pull rods are rotated to adjust the shift of the laser beams; the smaller the shift of the laser beams from the targets to an original point is, the better the parallelism is. The tool has a compact structure, is easy to operate, is high in parallelism control precision, and can be used for 6*2 and 8*4 dual-front-axle vehicles.