TRAXXAS TRX4 Trail Crawler Brass Front Knuckle Arms by GPM TRX4021BX  [TRX4021BX]

Brass front knuckle arms for TRX4

This upgrade set replaces the inner front knuckle components on TRX4-scale crawlers with brass units designed for consistent fit and added mass. Each brass arm is precision machined to maintain smooth rotation at the knuckle pivot while adding stabilising weight for low-speed trail work. The parts are intended for RC-scale use only and not for any real vehicle applications.

Installation notes: the brass inner knuckle locates in the knuckle inner case and uses the supplied stainless steel fasteners for assembly. Verify alignment and bearing clearance during fitment and use moderate threadlocker where appropriate for the button head screws to prevent loosening under vibration. No special tools are required beyond typical hex drivers for the listed screw sizes.

Included hardware and parts: inner part front knuckle 2pcs, stainless steel round head screw 3x16 2pcs, stainless steel round head screw 2.5x3 6pcs, stainless steel button head screw 2.5x8 4pcs. Each brass arm provides approximately 50g of external weight potential allowing tuning of front bias for improved traction and stability on steep or technical sections.

For TRX4 owners seeking durable inner knuckle replacements with added front weight, this brass set gives a straightforward swap that influences traction and steering feel without altering mounting geometry.