SPL Parts CRBN G29 Non-Adj Caster Rod Bushings for BMW Z4 G29 Toyota GR Supra

Vehicle Fitment

• 2019+ BMW Z4 sDrive20i (G29)
• 2019+ BMW Z4 sDrive30i (G29)
• 2019+ BMW Z4 M40i (G29)
• 2020+ Toyota GR Supra Base, Premium, and Launch Edition (A90/A91)

Fitment Notes

• Replaces the OE rubber caster rod (tension rod) inner bushings only - the OE caster rods/tension rod arms are retained. This is a bushing upgrade, not a full arm replacement.
• Non-adjustable (CRBN) - maintains factory caster geometry while eliminating rubber bushing compliance. For the adjustable version that provides +/- 4 degrees of caster adjustment, see SPL part #CRB G29.
• The BMW Z4 (G29) and Toyota GR Supra (A90) share the same CLAR platform and front suspension architecture - this part is confirmed to fit both vehicles.
• Sold as a pair - one pair covers both front caster rod positions. One pair per vehicle required.
• Professional installation is recommended. A full wheel alignment should be performed after installation to verify caster and alignment settings.
• Not compatible with heavily modified front suspension configurations that have altered the caster rod mounting geometry.

Features

• SPL Parts FKS Series non-adjustable front caster rod bushings (CRBN) for the 2019+ BMW Z4 G29 and 2020+ Toyota GR Supra A90 - replace the OE flexible rubber bushings with low-friction, articulating FK 1" spherical bearings to eliminate bushing deflection and reduce compliance under load
• Eliminating rubber bushing compliance maintains optimal suspension geometry during hard braking, cornering, and over bumps - where rubber deflects and temporarily alters caster and toe, reducing steering response and consistency
• FK Racing 1" spherical bearings with self-lubricating Teflon (PTFE) liners - massive bearing size for high load capacity and durability; maintenance-free design requires no lubrication after installation
• 6061-T6 aluminum bearing housing with outer knurl - precision interference fit for secure retention in the OE caster rod arm without fasteners
• Improves braking stability and handling feedback by maintaining accurate caster geometry throughout the full range of suspension motion, including under the high loads of track driving and spirited street use
• Made in the USA by SPL Parts - all materials sourced from US suppliers and manufactured to SPL's exacting tolerances

Specifications

• Part Number: CRBN G29
• Brand: SPL Parts
• Product Type: Non-Adjustable Front Caster Rod Bushings (FKS Series)
• Bearing: FK Racing 1" spherical bearings with self-lubricating Teflon (PTFE) liner
• Housing Material: 6061-T6 Billet Aluminum with outer knurl
• Adjustment: Non-adjustable - maintains OE caster geometry
• Sold As: Pair (2 pieces)
• OE Arms: Retained - bushing replacement only
• Origin: Made in USA

Included Components

• 2x 6061-T6 aluminum bearing housings with pressed-in FK 1" PTFE-lined spherical bearings

Product Description

The SPL Parts CRBN G29 is an FKS Series non-adjustable front caster rod bushing set engineered for the 2019+ BMW Z4 (G29) and 2020+ Toyota GR Supra (A90) - both sharing the same BMW CLAR platform front suspension architecture. These bushings replace the OE flexible rubber caster rod bushings with massive 1" FK Racing spherical bearings featuring self-lubricating Teflon liners, directly eliminating the compliance and deflection inherent in rubber that allows the caster rod to move under load. When the OE rubber bushings flex during hard braking, cornering, and over rough surfaces, suspension geometry temporarily shifts - altering caster and introducing inconsistency in steering feedback and handling response. The CRBN eliminates this deflection entirely, maintaining accurate geometry throughout the full range of suspension motion.

The non-adjustable CRBN is the correct choice when the goal is eliminating rubber compliance while retaining factory caster angles - ideal for lowered street builds, track days, and any application where improved steering response and braking stability are desired without requiring a full caster adjustment. For builds requiring caster correction or intentional caster increase, see SPL #CRB G29, which uses offset bearing spacers to provide +/- 4 degrees of caster adjustment. Sold as a pair, professional installation and a full wheel alignment are recommended after fitment. Proudly engineered and manufactured in the USA by SPL Parts.