Upper Arm Mount B for TRF421X Tamiya 3451581 (42391)  [3451581]

Details for Upper Arm Mount B on TRF421X

This is the replacement Upper Arm Mount B identified by part number 3451581 and linked to code 42391 for the TRF421X chassis. The component is supplied as a spare to restore or adjust the upper arm mounting point without changing the adjacent suspension or arm assemblies.

Operationally, the mount locates the upper arm relative to the shock tower and suspension mounting plate, influencing ride height, camber roll centre, and overall track stability when used during setup changes. Fit it to replace a damaged mount or to preserve the intended geometry after maintenance.

Fitting the part is straightforward for anyone with basic tools: remove the damaged mount using the original hex screws, align the replacement to factory orientation, and secure with the original fasteners. Check for suspension binding, confirm arm travel, and re-verify wheel alignment after an initial test lap.

Offered as a direct replacement, this part suits TRF421X owners seeking a like-for-like swap for part 42391 or a dependable option while adjusting chassis geometry.