Tamiya 51745 TRF421 Gear Differential Unit Set - Track tuning upgrade  [51745]

Refine your TRF421 with the Tamiya 51745 diff kit

The Tamiya 51745 Gear Differential Unit Set contains the internal components required to replace or adjust the differential on a TRF421. It is aimed at hobbyists who need dependable, tunable diff performance.

Control traction with different oil grades

Swapping oil grades in the gear differential alters how power is handed to each wheel, letting you tailor traction and rotation. Choose lighter oil for nimble response or heavier oil for steadier traction through fast bends.

Use front or rear mounting to change handling bias

Mount the unit in either the front or rear position on the TRF421 to shift the car's handling balance. This flexibility is useful when testing setups to address understeer or oversteer tendencies.