TRX4 Outer Portal Drive Housing 6061-T6 Aluminium Strength Set TRX4021A by GPM  [TRX4021A]

6061-T6 Portal Drive Outer Housing for TRX4

The TRX4021A aluminium outer portal drive housing is supplied as an 18 piece aftermarket set for TRX4 Trail Crawler knuckle assemblies and is suitable for installation on either front or rear portals. Machined from 6061-T6 aluminium, these housings are intended to replace the stock plastic outer shells and provide a firmer mounting surface to help maintain inner gear alignment under crawling loads.

The set includes stainless steel cap head screws and is dimensioned for direct replacement with original plastic components, allowing a largely plug-and-play installation without modifying adjacent parts. The 3D-machined profile and precision-cut edges help preserve correct gear mesh and running clearance within the portal assembly.

In use the housings reduce flex in the outer shell to stabilise inner gears, aiding consistent engagement and improving steering response on demanding sections. They reference a midpoint distance of 93mm between damper and tie rod as a helpful siting figure when mounting to standard TRX4 knuckle configurations.