Transmission Mount
A structural support component made of metal and rubber that secures the transmission to the chassis and absorbs vibration.
A transmission mount is a structural component that holds the transmission securely in place, aligning it with the engine and the driveshaft. It is bolted between the transmission casing and the vehicle's chassis or subframe, acting as one of the primary mounting points for the vehicle's drivetrain.
The mount is constructed of a heavy metal bracket bonded to a thick rubber or polyurethane block. This rubber section is critical: it isolates the vehicle's cabin from the noise, vibrations, and harshness (NVH) generated by the spinning gears and torque inside the transmission, while allowing for slight engine movement.
Over time, the rubber in a transmission mount can crack, dry rot, tear, or become saturated with leaking oil. When the mount fails, the transmission can shift out of alignment. This leads to symptoms such as a clunking noise when shifting gears, excessive drivetrain vibration felt through the floorboards, and acceleration shimmy.
Replacing a worn transmission mount is important because a loose transmission puts extra stress on the driveshaft, universal joints, and engine mounts. Mechanics inspect the mounts during routine oil changes by checking for cracks or excessive play.