Examination
Observe the gearbox mounts as the assistant lifts and pushes down on the gearbox. If the mount rubber separates from the steel base or the transmission case moves up but does not lower, indicating that the mount has reached its bottom limit, replace the mount.
Replacement
Disconnect the wire from the negative battery terminal.
Support the gearbox with a jack through a wooden block.
Turn out bolts of fastening of a support of the power unit to the engine or a transmission.
Unscrew the nuts securing the support to the body and remove the support.
Correctly position the new support and screw in the bolts of fastening to the engine or gearbox. Tighten the bolts to the required torque.
Screw on nuts of fastening of support to a body and tighten them the demanded moments.
Remove the jack and connect the wire to the negative battery terminal.