The invention discloses a motor vehicle speed reduction piece. The motor vehicle speed reduction piece comprises a body, a first hole, a plurality of second holes and a plurality of third holes, wherein the first hole is formed in the center of the body, the second holes are evenly formed around the first hole, and the third holes are evenly and densely distributed in the periphery of the body. The motor vehicle speed reduction piece is characterized in that a nitrogen-carbon compound layer is arranged on the surface of a braking plane of the speed reduction piece. The motor vehicle speed reduction piece is resistant to wear and corrosion, low in noise and good in damping effect.