HPI Baja Rear Gear Box Alloy Service Part BJ012 by GPM  [BJ012]

Rear gearbox solution for HPI Baja

The BJ012 serves as an aftermarket alloy rear gear box for HPI Baja scale RC cars. It secures the spur gear train and axle bearings while providing a stiff mounting location for the rear differential and related driving components.

It is intended for hobbyists needing replacement or upgrade parts: swapping broken housings, correcting mesh problems, and replacing plastic housings with a corrosion-resistant alloy option. The alloy construction adds stiffness against typical off-road forces while maintaining scale-appropriate fit.

Installation notes: the unit installs into the position of the original rear gear box and uses the existing screw locations and internal gearing arrangement found in the HPI Baja assembly. Standard service procedure applies—clean mating faces, inspect internal gears and bearings prior to refit, and use threadlocker where the chassis documentation advises.

Tuning and maintenance role: installing this rear housing can aid in keeping a stable gear mesh when addressing wear or post-impact repairs. It does not alter gear ratios or require ESC tuning, but combined with correct spur and pinion settings it can lower flex-induced backlash during demanding use.

The BJ012 alloy rear gear box is a direct aftermarket swap that focuses on improving structural durability and maintaining drivetrain alignment for HPI Baja vehicles during maintenance and setup sessions.