This metal-rubber bushing isolates the cab structure from chassis vibration and noise. It sits at each mounting point between the cab frame and the tractor chassis, absorbing shock loads that would otherwise transmit directly to the operator station. The rubber element deforms elastically under load to dampen low-frequency oscillations, while the metal sleeve provides a rigid inner bore for the mounting bolt. A worn bushing allows metal-to-metal contact at the mount, producing audible rattling and transferring vibration into the cab. On reinstallation, tighten the mounting bolt to the specified torque to maintain the correct preload on the rubber element.