TRAXXAS TRX4 Front/Rear Aluminium Gearbox Upgrade TRX4012 by GPM  [TRX4012]

Front and rear aluminium gearbox shells for TRX4

This TRX4012 aluminium gearbox kit from GPM serves as a direct-scale replacement for TRAXXAS TRX4 gearbox shells, aimed at strengthening the mounting areas for front differential assemblies, suspension links, and C-hub connections on crawler rigs. The upgrade focuses on chassis rigidity and does not alter gear ratios or the basic driveline layout.

Machined aluminum housings provide lower flex than stock plastic cases, helping to keep suspension link geometry consistent during slow, technical crawling. Fitting the housings involves removing the original front and rear gearbox shells, transferring internal gears and bearings, and reusing factory driveline components. There is no requirement to change motors, ESCs, or servos.

Package contents as listed by the supplier include the following fasteners: Stainless Steel Cap Head Screw 2.5x14 - 4 pcs, Stainless Steel Flat Head Screw 2.5x10 - 4 pcs, Stainless Steel Flat Head Screw 2.5x6 - 6 pcs. These screws secure the gearbox halves, link mount points, and C-hub attachments.

For enthusiasts chasing a firmer front and rear diff mounting solution, the TRX4012 aluminium gearbox reduces housing flex and comes with the stainless fasteners listed; installation follows TRX4 stock layout and requires standard gear and bearing transfer.