TRX-4 Brass Inner Front Knuckle Arms TRX4021BX by GPM  [TRX4021BX]

CNC machined brass inner knuckles for TRX-4 axles

This upgrade set replaces the inner front knuckle components on TRX-4 scale crawlers with CNC-finished brass arms engineered for precise fit and controlled mass distribution. The machined bores and bearing surfaces maintain smooth pivot rotation while the additional weight allows fine tuning of front bias for improved low-speed traction. These components are intended strictly for RC use and are not for application on full size vehicles.

Technical installation notes: the brass inner knuckle locates into the knuckle inner case and is secured using the supplied stainless steel fasteners. During assembly confirm bearing tolerances, axial play and alignment, and use moderate threadlocker on the specified button head screws to prevent vibrational loosening. No specialised tooling is required beyond common hex drivers matching 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 contributes approximately 50g of external weight potential enabling front-end bias adjustments for steep or technical sections without altering mounting geometry.

For builders seeking durable, precisely machined inner knuckles that add predictable front ballast, this TRX4021BX brass kit provides a direct-fit upgrade to influence traction and steering characteristics.