Abstract: A noise reduction apparatus for a carrier roller in a crawler tractor, which includes first and second dimpled, annular guard members, each having a steel plate with a noise-absorbing member bonded thereto, and a third annular guard member having a noise-absorbing member and a layer of vibration damping material. The first and second guard members are removably secured to the opposite side faces of the carrier roller, while the third guard member is closely fitted, through the medium of the layer of the aforesaid vibration damping material, into an annular groove defined about the periphery of the central portion of the carrier roller. The noise-absorbing members of the first and second guard members are positioned on the respective inner surfaces of the steel plates.